The document provides an overview of genetic engineering and its history. It discusses the basics of genetic engineering, which involves isolating and copying genetic material of interest using molecular cloning methods and inserting new DNA into the host genome. The history of genetic engineering is then explored, from early discoveries like Mendel's work with inheritance in peas to more modern developments like recombinant DNA techniques, PCR, and the creation of the first transgenic animal. A number of influential scientists in the field are also highlighted. The document aims to inform the reader about genetic engineering, related techniques, and its progression over time.
genetic engineering: Genetic engineering, also called genetic modification, is the direct manipulation of an organism's genome using biotechnology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. Many organism are manipulated with the help genetic engineering useful for mankind.
genetic engineering: Genetic engineering, also called genetic modification, is the direct manipulation of an organism's genome using biotechnology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. Many organism are manipulated with the help genetic engineering useful for mankind.
History of Genetic Engineering
Tools of Genetic Engineering
Principles of rDNA technology
Applications of Genetic Engineering in agriculture medicine and orthodontics
This presentation gives an brief idea about the applications of genetic engineering which is of at most importance to humans. Provided along with this slide is an example which makes it easier to understand the concept.
The direct microinjection of DNA into the cytoplasm or nuclei of cultured cells is sometimes used as a transfection method. It is highly efficient at the level of individual cells. The most significant use of this technique is introduction of DNA into the oocytes, eggs and embryos of animals, either for transient expression analysis (e.g. in fish or Xenopus) or to generate transgenic animals (e.g. mice, Drosophilathis). The procedure is time consuming and only a small number of cells can be treated. Originally, this technique was used for the transformation of cells that were resistant to any other method of transfection. Stable transfection efficiencies are extremely high, in the order of 20%, and very small quantities of DNA are sufficient.
This technique provides direct nuclear delivery of DNA avoiding the endogenous pathway and also ensures that the DNA is delivered intact. Microinjection is suitable for the introduction of large vectors such as YACs into the pronuclei of fertilized mouse eggs. DNA delivered in this manner must be very pure so it needs a lot of preparation as it is necessary to avoid fragmentation. Shearing can also occur in the delivery needle, and large DNA fragments are often protected by suspension in a high salt buffer and/or mixing with polyamines and other protective agents. Now transfection of cultured cells is automated with computer-controlled micromanipulation and microinjection processes as well as the automated production of injection capillaries and the standardization of cell preparation procedure.
GENE CLONING,ITS HISTORY, NEW ADVENT IN GENE CLONING, PCR IMPORTANCE ,APPLICATION OF GENE CLONING,STEPS OF GENE CLONING,Antisense technology,Gene cloning in agriculture,Somatic cell therapy,Role of gene cloning in identification of genes responsible for human diseases,Synthesis of other recombinant human proteins and recombinant vaccines
Gene cloning in medicine,Recombinant protein from yeast,Problems with the production of recombinant protein in E.coli ,Expression of foreign genes in E.coli,Production of recombinant protein ,PCR can also be used to purify a gene,Obtaining a pure sample of a gene by cloning,Why gene cloning and PCR are so important,The advent of gene cloning and the polymerase
chain reaction.
History of Genetic Engineering
Tools of Genetic Engineering
Principles of rDNA technology
Applications of Genetic Engineering in agriculture medicine and orthodontics
This presentation gives an brief idea about the applications of genetic engineering which is of at most importance to humans. Provided along with this slide is an example which makes it easier to understand the concept.
The direct microinjection of DNA into the cytoplasm or nuclei of cultured cells is sometimes used as a transfection method. It is highly efficient at the level of individual cells. The most significant use of this technique is introduction of DNA into the oocytes, eggs and embryos of animals, either for transient expression analysis (e.g. in fish or Xenopus) or to generate transgenic animals (e.g. mice, Drosophilathis). The procedure is time consuming and only a small number of cells can be treated. Originally, this technique was used for the transformation of cells that were resistant to any other method of transfection. Stable transfection efficiencies are extremely high, in the order of 20%, and very small quantities of DNA are sufficient.
This technique provides direct nuclear delivery of DNA avoiding the endogenous pathway and also ensures that the DNA is delivered intact. Microinjection is suitable for the introduction of large vectors such as YACs into the pronuclei of fertilized mouse eggs. DNA delivered in this manner must be very pure so it needs a lot of preparation as it is necessary to avoid fragmentation. Shearing can also occur in the delivery needle, and large DNA fragments are often protected by suspension in a high salt buffer and/or mixing with polyamines and other protective agents. Now transfection of cultured cells is automated with computer-controlled micromanipulation and microinjection processes as well as the automated production of injection capillaries and the standardization of cell preparation procedure.
GENE CLONING,ITS HISTORY, NEW ADVENT IN GENE CLONING, PCR IMPORTANCE ,APPLICATION OF GENE CLONING,STEPS OF GENE CLONING,Antisense technology,Gene cloning in agriculture,Somatic cell therapy,Role of gene cloning in identification of genes responsible for human diseases,Synthesis of other recombinant human proteins and recombinant vaccines
Gene cloning in medicine,Recombinant protein from yeast,Problems with the production of recombinant protein in E.coli ,Expression of foreign genes in E.coli,Production of recombinant protein ,PCR can also be used to purify a gene,Obtaining a pure sample of a gene by cloning,Why gene cloning and PCR are so important,The advent of gene cloning and the polymerase
chain reaction.
genetic engineering, future perspectives and QC validationSana Rubab
this ppt will help you in studying genetic engineering, its introduction, history, basics, methods and procedures, QC validation, future perspectives and applications.
Howdy! This is a fantastic biology literature review example that we've prepared for you. If you need more go to https://www.literaturereviewwritingservice.com/biology-literature-review-example-and-writing-tips/
The project was a great success, delivering the first rough draft human genome sequence in 2000 and the final high-quality version in April, 2003, ahead of schedule and under budget. For years, many considered the Human Genome Project to be biology's equivalent to "Man on the moon". This slide tends to explain the benefits of such project to medical diagnosis, treatment and management in India.
The Human Genome Project (HGP) was an international scientific research project with the goal of determining the base pairs that make up human DNA, and of identifying and mapping all of the genes of the human genome from both a physical and a functional standpoint.
Human Genome Project (HGP)
Main objectives Human Genome Project (HGP)
Goals for the HGP
Medical Implications
Applications of HGP
Timeline of HGP
Technical aspects in HGP
Mapping strategies
Sequencing strategies
. Shotgun sequencing method
Sanger sequencing method
Outcomes of HGP
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
1. GENETIC
ENGINEERING
By,
Dr. Priyanka Sharma
II year MDS
Department of Public Health Dentistry
JSS Dental College & Hospital 1
1
2. CONTENTS
1) INTRODUCTION
2) BASICS OF GENETIC ENGINEERING
3) HISTORY OF GENETIC ENGINEERING
4) GENERAL APPLICATION OF GENETIC ENGINEERING
5) GENETIC ENGINEERING IN DENTISTRY
- VARIOUS TECHNIQUES OF GENETIC ENGINEERING
6) GENETIC COUNSELLING & ROLE OF DENTIST
7) SUMMARY
8) CONCLUSION
9) REFERENCES
2
2
4. INTRODUCTION
Genetic engineering is a part of
biotechnology.
Biotechnology is the use of living
systems and organisms to develop or
make useful products, or "any
technological application that uses
biological systems, living organisms or
derivatives thereof, to make or modify
products or processes for specific use"
(UN Convention on Biological
Diversity, Art. 2).
4
4
5. INTRODUCTION continuation..
Biotechnology is a huge topic.
Its hard to define its exact boundaries.
Some European scientists divide the field into :
1) Red biotechnology
2) Green biotechnology
Some divides it into :
1) White
2) Blue
Biotechnology falls under many umbrellas
which is basically considered as life science.
Book : Biotechnology & Genetic engineering (Kathy wilson peacock)
5
2010,Edi:1 : Page No. 4 (Chapter 1)
5
7. 7
INTRODUCTION continuation..
• Genetics – science of genes, heredity
and variation in living organisms.
• Genetics deals with the molecular structure
and function of genes, and gene behavior in
context of a cell or organism (e.g. dominance
and epigenetics ).
• Patterns of inheritance from parent to
offspring, and gene distribution, variation and
change in populations = Population genetics.
7
Book : Genetics and the Organism: Introduction
8. 8
INTRODUCTION continuation..
Essence
Of
Genetics
• Chromosome
• Packaged and organized chromatin, a complex of
macromolecules found in cells, consisting of DNA, protein and
RNA.
Essence
Of
Genetics
• DNA
• A molecule that encodes the genetic instructions used in the
development and functioning of all known living organisms and
many viruses.
Essence
Of
Genetics
• Genetic Variation
• Permanent change in the chemical structure of genes brought
about by mutation, important in providing genetic material for
natural selection.
Essence
Of
Genetics
• Heredity
• The study of heredity in biology is called genetics, which includes
the field of epigenetics.
8
Book : Genetics and the Organism: Introduction
15. BASICS OF
GENETIC ENGINEERING
• Different terms used for genetic
engineering :
1) Gene manipulation
2) Gene cloning
3) Recombinant DNA technology
4) Genetic modification
5) New genetics
An Introduction to Genetic Engineering (Desmond S. T. Nicholl) Edi :3rd 2008
15
Chapter 2 . Page 3
15
16. Direct manipulation of an organism's
genome using biotechnology .
First isolating and
copying the
genetic material of
interest
using molecular
cloning methods
Generate a
DNA sequence
New DNA
inserted in the host
genome
BASICS OF
GENETIC ENGINEERING CONTINUATION..
An Introduction to Genetic Engineering (Desmond S. T. Nicholl)
Edi :3rd 2008 Chapter 2.
16
17. 17
Miller et al(2000). An Introduction to Genetic Analysis (7th ed.).
17
18. 18
18
CONTENTS
1) INTRODUCTION
2) BASICS OF GENETIC ENGINEERING
4) GENETIC ENGINEERING IN DENTISTRY
- VARIOUS TECHNIQUES OF GENETIC ENGINEERING
5)GENETIC COUNSELLING AND ROLE OF A DENTIST
1) SUMMARY
2) CONCLUSION
3) REFERENCES
19. Genetic inheritance was first
discovered by Gregor Mendel in 1865
following experiments crossing peas.
• Although largely ignored for 34 years he
provided the first evidence of hereditary
segregation and independent assortment
In 1889 Hugo de Vries came up with the name
"(pan)gene" for after postulating that particles
are responsible for inheritance of characteristics
Term "genetics" was coined by William
Bateson in 1905.
19
20. In 1928 Frederick Griffith proved the
existence of a "transforming principle" involved
in inheritance, which Avery, MacLeod and
McCarty later (1944) identified as DNA.
Edward Lawrie Tatum and George Wells
Beadle developed the central dogma that genes
code for proteins in 1941.
The double helix structure of DNA was
identified by James Watson and Francis
Crick in 1953.
20
21. In 1970 Hamilton Smiths lab
discovered restriction enzymes that allowed
DNA to be cut at specific places and separated
out on an electrophoresis gel.
• This enabled scientists to isolate genes from an
organism's genome.
DNA ligases, that join broken DNA together,
had been discovered earlier in 1967 and by
combining the two enzymes it was possible to
"cut and paste" DNA sequences to
create recombinant DNA.
Plasmids, discovered in 1952, became
important tools for transferring information
between cells and replicating DNA sequences.
21
22. Frederick Sanger developed a method for
sequencing DNA in 1977, greatly increasing the
genetic information available to researchers
Polymerase chain reaction (PCR), developed
by Kary Mullis in 1983, allowed small sections
of DNA to be amplified and aided identification
and isolation of genetic material
Artificial competence was induced
in Escherichia coli in 1970 when Morton
Mandel and Akiko Higa showed that it could
take up bacteriophage λ after treatment with
calcium chloride solution (CaCl2).
22
23. Two years later, Stanley Cohen showed that
CaCl2 treatment was also effective for uptake of
plasmid DNA.
Transformation using electroporation was
developed in the late 1980s, increasing the
efficiency and bacterial range
In 1972 Paul Berg utilised restriction enzymes
and DNA ligases to create the first recombinant
DNA molecules.
23
24. • Herbert Boyer and Stanley N. Cohen took
Bergs work a step further and introduced
recombinant DNA into an bacterial cell.
In 1981 the laboratories of Frank Ruddle,
Frank Constantini and Elizabeth Lacy
injected purified DNA into a single-cell mouse
embryo and showed transmission of the genetic
material to subsequent generations.
On June 19, 2013 the leaders of three research
teams who originated the technology, Robert T.
Fraley of Monsanto; Marc VanMontagu of Ghent
University in Belgium and founder of Plant Genetic
Systems and CropDesign ; and Mary-Dell
Chilton ofWashington University in St.
Louis and Syngenta were awarded with the World
Food Prize
Gordon, J.; Ruddle, F. (1981). "Integration and stable germ line transmission 24
of
genes injected into mouse pronuclei". Science 214 (4526): 1244.
25. The first recorded knockout mouse was created
by Mario R. Capecchi, Martin
Evans and Oliver Smithies in 1989. They are
used to study gene function and make useful
models of human diseases.
In 1992 onco-mice with tumor suppressor
genes knocked out were generated.
Creating Knockout rats are much harder and has
only been possible since 2003
Bacteria synthesising human insulin were
developed in 1979, being used as a treatment for
the first time in 1982
Zan, Y; Haag, J. D.; Chen, K. S.; Shepel, L. A.; Wigington, D; Wang, Y. R.; Hu, R; Lopez-Guajardo, C.
C.; Brose, H. L.; Porter, K. I.; Leonard, R. A.; Hitt, A. A.; Schommer, S. L.; Elegbede, A. F.; Gould, M.
N. (2003). “Production of knockout rats using ENU mutagenesis and a yeast-based screening
25
assay". Nature Biotechnology 21(6): 645–51.
26. 26
In 1988 the first human antibodies were
produced in plants.
The first animal to synthesise transgenic
proteins in their milk were mice, engineered
to produce human tissue plasminogen
activator.
With the discovery of microRNA in 1993
came the possibility of using RNA
interference to silence an organisms
endogenous genes
- Peng, S. (2006). "A transgenic approach for RNA interference-based
genetic screening in mice". Proceedings of the National
Academy of Sciences 103 (7): 2252–2220.
- Vaucheret, H.; Chupeau, Y. (2011). plant miRNAs regulate gene
expression in animals Cell Research 22 (1): 3–5.
27. 27
Improved our
understanding of
genetics.
His research helped to
make organ
transplantations
possible.
Dr. Bernard Amos
27
28. • His work cloned frogs
laid the foundations
for somatic cell
nuclear transfer, the
application of which
led to Dolly the sheep.
28
John Gurdon
28
29. Worked out the
Structure of
Proteins.
29
Linus Pauling
29
32. • He noticed that there is
a pattern in the 4 bases:
Adenine, Guanine,
Cytosine and Thymine.
32
• A=T and G=C.
Erwin Chargaff
32
33. In 1973 created
a transgenic
mouse by
introducing foreign
DNA into its embryo,
making it the world’s
first transgenic
animal.
33
Rudolf Jaenisch
33
34. 34
34
CONTENTS
1) INTRODUCTION
2) BASICS OF GENETIC ENGINEERING
3) HISTORY OF GENETIC ENGINEERING
5) GENETIC ENGINEERING IN DENTISTRY
- VARIOUS TECHNIQUES OF GENETIC ENGINEERING
6) 5)GENETIC COUNSELLING AND ROLE OF A DENTIST
7) SUMMARY
8) CONCLUSION
9) REFERENCES
35. GENERAL APPLICATIONS OF
GENETIC ENGINEERING
][38]
35
Eg: transgenic plants produce natural
pesticide to resist to pest
35
36. Engineered Mammals
A monkey named ANDi,
for "inserted DNA", in a
picture released in
January 2001. ANDi was
born in October 2000 at
the Oregon Health
Science University after
receiving an extra bit of
genetic material to
become the world's first
genetically modified
non-human primate
36
36
37. 37
Cloning Dolly
• Sheep A: donate body cell nucleus
• Sheep B: donate an egg cell without nucleus
• Sheep C: surrogate mother
A B C
Dolly
37
Who’s its
mother?
38. 38
38
CONTENTS
1) INTRODUCTION
2) BASICS OF GENETIC ENGINEERING
3) HISTORY OF GENETIC ENGINEERING
4) GENERAL APPLICATION OF GENETIC ENGINEERING
6) 5)GENETIC COUNSELLING AND ROLE OF A DENTIST
7) SUMMARY
8) CONCLUSION
9) REFERENCES
40. TECHNIQUES
OF
GENETIC ENGINEERING
Tools and techniques
Methods in recombinant DNA
technology
Genetically modified organisms
Genetic treatments
40
40
41. 41
TECHNIQUES
OF
GENETIC ENGINEERING
Methods in recombinant DNA
technology
Genetically modified organisms
Genetic treatments
41
42. DNA: The Raw Material
– Heat-denatured DNA
• DNA strands separate if heated
to just below boiling
• Exposes nucleotides
• Can be slowly cooled and
strands will renature
42
42
43. Restriction Endo-nucleases
• Enzymes that can clip strands of DNA
crosswise at selected positions
• Each has a known sequence of
4 to 10 pairs as its target
• Can recognize and clip at palindromes
43
43
44. • Can be used to cut DNA in to smaller
pieces for further study or to remove
and insert sequences.
• Can make a blunt cut or a “sticky end”
• The pieces of DNA produced are
called restriction fragments.
• Differences in the cutting pattern of specific
restriction endonucleases give rise to
restriction fragments of differing lengths-restriction
fragment length polymorphisms.
44
44
46. Ligase and Reverse Transcriptase
• Ligase: Enzyme necessary to seal
sticky ends together
• Reverse transcriptase: enzyme that is
used when converting RNA into DNA.
46
46
48. ANALYSIS OF
DNA
Gel
electrophoresis
Polymerase
Chain Reaction
48
48
49. 49
49
Gel electrophoresis: produces a readable
pattern of DNA fragments
50. GEL ELCTROPHORESIS
• APPLICATIONS:
Estimation of the size of DNA
molecules following restriction
enzyme digestion, e.g. in restriction
mapping of cloned DNA.
Analysis of PCR products, e.g. in
molecular genetic diagnosis or genetic
fingerprinting.
50
50
51. 51
51
• Some techniques to analyze DNA and
RNA are limited by the small amounts of
test nucleic acid available
• Polymerase chain reaction (PCR)
rapidly increases the amount of DNA in a
sample
• So sensitive- could detect cancer from a
single cell
• Can replicate a target DNA from a few
copies to billions in a few hours
53. 53
53
Three Basic Steps that Cycle
• Denaturation
– Heat to 94°C to separate in to two strands
– Cool to between 50°C and 65°C
• Priming
– Primers added in a concentration that favors binding
to the complementary strand of test DNA
– Prepares the two strands (amplicons) for synthesis
• Extension
– 72°C
– DNA polymerase and nucleotides are added
– Polymerases extend the molecule
• The amplified DNA can then be analyzed
54. 54
54
• Relative sizes of nucleic acids
usually denoted by the number of
base pairs (bp) they contain.
• DNA Sequencing: Determining the
Exact Genetic Code
– Most detailed information comes from
the actual order and types of bases-
DNA sequencing
– Most common technique: Sanger DNA
sequence technique
56. 56
56
• Two different nucleic acids can hybridize by uniting at
their complementary regions.
• Gene probes: specially formulated oligonucleotide
tracers
– Short stretch of DNA of a known sequence
– Will base-pair with a stretch of DNA with a
complementary sequence if one exists in the test sample
• Can detect specific nucleotide sequences in unknown
samples.
• Probes carry reporter molecules (such as radioactive or
luminescent labels) so they can be visualized.
• Southern blot- a type of hybridization technique
57. 57
57
• Southern blotting involves the transfer of DNA
from a gel to a membrane, followed by detection
of specific sequences by hybridization with a
labeled probe.
• Northern blotting, RNA is run on a gel.
• Western blotting entails separation of proteins on
an SDS gel, transfer to a nitrocellulose membrane,
and detection proteins of interest using antibodies.
58. 58 FIGURE 21: Southern blot: Identifying Specific DNA Fragments
(Edward Southern--the pioneer)
or gentle vacuum
pressure
Drying or exposure
to UV light
Probes: Isotope or chemical
Gel is soaked in
alkali buffer to
denature DNA
59. Northern blotting is similar to Southern blotting,
but involves the transfer of RNA from a gel to a
membrane
RNA
59
60. Northern blotting: Measuring gene activity
Poly(A)+ RNA: from rat tissues
Probe: G3PDH (glyceraldehyde-3-phosphate dehydrogenase)
60
61. Western blotting
61
• Western blotting entails separation of proteins on
an SDS gel, transfer to a nitrocellulose membrane,
and detection proteins of interest using antibodies.
wikipedia
63. Blotting Methods
63
• Antibodies can recognize the protein of interest or
an epitope tag.
• epitope tag – A short peptide sequence that
encodes a recognition site (“epitope”) for an
antibody, typically fused to a protein of interest for
detection or purification by the antibody.
Human influenza hemagglutinin (HA): YPYDVPDYA
The HA tag is derived from the HA-molecule corresponding to amino
acids 98-106 has been extensively used as a general epitope tag in
expression vectors.
65. 65
65
• Probes applied to intact cells
• Observed microscopically for the
presence and location of specific
genetic marker sequences
• Effective way to locate genes on
chromosomes
66. • Gene expression array are used to detect the
level of all the expressed genes in an
experimental sample.
• SNP arrays permit genome-wide genotyping of
single nucleotide polymorphisms. =>use
allele-specific oligonucledtide probe
• Array comparative genome hybridization
(array-CGH) allows the detection of copy
number changes in any DNA sequence
compared between two samples.
66
67. DNA 67
Microarrays
• DNA microarrays
comprise known DNA
sequences spotted or
synthesized on a small
chip.
Microarrays show the
levels of all the
expressed genes in an
experimental sample.
68. 68
TECHNIQUES
OF
GENETIC ENGINEERING
Tools and techniques
Genetically modified organisms
Genetic treatments
68
69. 69
69
Methods in Recombinant DNA
Technology
• Primary intent of recombinant DNA
technology- deliberately remove
genetic material from one organism and
combine it with that of a different
organism.
• Form genetic clones
– Gene is selected
– Excise gene
– Isolate gene
– Insert gene into a vector
– Vector inserts DNA into a cloning host
71. 71
71
Technical Aspects of Recombinant
DNA and Gene Cloning
• Strategies for obtaining genes in an
isolated state
– DNA removed from cells, separated into
fragments, inserted into a vector, and
cloned; then undergo Southern blotting and
probed
– Gene can be synthesized from isolated
mRNA transcripts
– Gene can be amplified using PCR
• Once isolated, genes can be maintained
in a cloning host and vector (genomic
library)
72. 72
72
Characteristics of Cloning
Vectors
• Capable of carrying a significant piece of the
donor DNA
• Readily accepted by the cloning host
• Must have a promoter in front of the cloned
gene
• Vectors (such as plasmids and
bacteriophages) should have three important
attributes:
– An origin of replication somewhere on the
vector
– Must accept DNA of the desired size
– Contain a gene that confers drug resistance to
their cloning host
77. CONVENTIONAL APPROACH
77
77
OF TREATMENT
• Enzyme induction by drugs
• Replacement of deficient enzymes /
proteins
• Replacement of deficient vitamin / co-enzyme
• Replacement of deficient product
• Substrate restriction in diet
• Drug therapy
• Drug avoidance
• Replacement of diseased tissue
• Removal of disease tissue
78. Genomic medicine 78
use of genotypic analysis (DNA
testing) to enhance quality of medical
care, including
78
- presymptomatic
identification
- preventive intervention
- selection of
pharmacotherapy
- design of medical care
79. 79
79
GENE THERAPY
Replacement of a deficient gene /
gene product or correction of an
abnormal gene.
2 TYPES:
i. Germ-line gene therapy – changes
will be passed on to subsequent
generations
ii. Somatic Cell gene therapy –
changes will not be passed on to
future generations
80. Gene Therapy
• Gene transfer for the purpose of
treating human disease.
• Transfer of new genetic material as
well as manipulation of existing
genetic material.
(Genetic engineering)
in vivo ex vivo
80
89. Gene therapy
• Pain
Virus vector – mediated transfer of genes
encoding opiate peptides
peripheral & central neurons
Anti-noceptive effects
89
Direct gene delivery – articular surface TMJ
90. • Keratinocytes Gene therapy – systemic
human aplipoprotein E, factor IX,
growth hormone and IL-10 into
bloodstream.
• DNA vaccinations
Gene therapy
90
94. Gene therapy
94
Future Strategies of Gene Therapy
in Preventing Periodontal Diseases
• Gene Therapeutics-Periodontal
Vaccination
• Genetic Approach to Biofilm
Antibiotic Resistance
• An In vivo Gene Transfer by
Electroporation for Alveolar
Remodelling
• Tight Adherence Gene for the Control
of Periodontal Disease Progression
• Antimicrobial Gene Therapy to
Control Disease Progression 94
98. Anti-angiogenesis
therapy
Transfer
gene to
tumor cells
to block
angiogenesis
Inhibit tumor
progression
Pre-clinical
Drug
resistance
gene therapy
Transfer
cytoprotectiv
e gene
Decrease
toxicity of
chemotherap
y
Clinical trial
Tumor-cell
killing
viruses
Introduce
viruses that
destroy
tumor cells
as part of
replication
cycle
Kill tumor
cells
Pre-clinical
Suicide gene
therapy
Transfer
gene
encoding
pro-drug
activating
enzyme
Kill tumor
cell &
enhance
chemotherap
y
Clinical trial
98
99. 99 HUMAN GENOME
99
PROJECT
Objectives:
i. Sequencing of human genomes
ii. Mapping of human inherited diseases
iii. Development of new DNA
technologies
iv. Development of bio-informatics
v. Comparitive Genomics
vi. Functional Genomics
100. 100
TISSUE ENGINEERING
• Tissue Engineering is a general name
of biomedical fields to enable cells to
enhance their proliferation,
differentiation, and morphological
organization for induction of tissue
regeneration, resulting in regenerative
medical therapy of diseases.
100
101. 101
Stem cells in regenerative medicine
• A stem cell is defined as a cell that can
continuously produce unaltered
daughters and, furthermore, has the
ability to generate cells with different
and more restricted properties.
• These cells can either multiply
(progenitors or transit amplifying cells)
or be committed to terminal
differentiation.
• Stem cells are self-renewing and thus
can generate any tissue for a lifetime.
• This is a key property for a successful
therapy. 101
107. 107
GENETIC COUNSELLING
A process of communication and education
which addresses concerns relating to the
development and / or transmission of a
hereditary disorder.
STEPS IN GENETIC COUNSELLING
107
- Diagnosis
- Risk assessment
- Communication
- Discussion of options
- Long term contact & support
108. 108
108
DIAGNOSIS
• History
• Examination
• Investigation
• Only when accurate diagnosis is
possible
• When etiological heterogeneity is
present
109. 109
RISK ASSESSMENT
The good side of the coin should also
be emphasized
109
ARBITRARY GUIDE
1 in 10 - High risk
1 in 20 - Low risk
Intermediate values - Moderate risk
110. 110
LONG TERM CONTACT &
110
SUPPORT
• Counselling centers should maintain
informal contact with families
through a network of genetic
associates
• Genetics registers provide a useful
means in ensuring effective contact
111. 111
NEONATAL SCREENING
111
To prevent subsequent morbidity
POPULATION CARRIER
SCREENING
The branch of medical genetics
which is concerned with
screening and the prevention of
genetic disease on a population
basis is known as community
genetics.
112. PRENATAL DIAGNOSIS 112
Ability to detect abnormality in an
unborn child.
112
TECHNIQUES
I. Non invasive
- Maternal Serum screening
- Ultra sound
II. Invasive
- Amniocentesis
- Chorionic Villus Sampling
113. INDICATIONS FOR 113
113
PRENATAL DIAGNOSIS
• Advanced maternal age
• Previous child with a genetic
abnormality
• Family History of
- Chromosome abnormality
- Single gene disorder
- Neural tube defect
- Other congenital structural
abnormalities
• Abnormalities identified in pregnancy
Eg. Poor fetal growth
114. 114
114
• Other High risk factors
- Parental Consanguinity
- Poor obstetric history
Eg: Recurrent miscarriages
Previous unexplained still
birth
- Maternal illness
Eg: Poorly controlled IDDM
Maternal epilepsy
Treatment with Sodium
Valproate
115. IDENTIFY GENETIC DISEASE
1. Build the pedigree
2. Analyse
3. Risk of recurrence
4. Decision
115
116. Role of dentist as genetic
counselor
• Oral manifestations
• Correct identification
• Diagnosis
• Referral
• Suggestion
• Screening for dental diseases
DNA probes
116
119. 119
Genetic
engineering
Enabling
technology
Cutting,modifying
and joining DNA
molecules
enzymes
Generation
of DNA
fragments
Restriction
enzyme
DNA Ligase
Joining to a
vector or DNA
Molecule
Introduction
into the host
cell
Selection of
desired
sequence
Arose from
Gene cloning
Recombinant
DNA
Molecular cloning
Pure science,
Biotechnology,
Medicine,
Dentistry
Legal and
ethical
considerations
Microbial &
Molecular
genetics
In 1972
Stanford
University
Is also known as
Has application in
But raises some
was first achieved
Is an
That involves
using
Such as
Requires four steps
Can be used for
used for
120. CONCLUSION
120
• Biotechnology as a fast developing
technology as well as science , has
already shown its impact on different
aspects of day-to-day human life such
as public health pharmaceuticals, food
and agriculture industries,
bioenergetics and information
technology.
120
121. 121
• As it has potential to ensure food
security, dramatically reduce hunger
and malnutrition and reduce rural
poverty , particularly in developing
countries , Now it is very clear that
biotechnology is the key technology
for the 21st century and the science of
the future.
121
122. References
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128
Editor's Notes
In 1907 a bacterium that caused plant tumors, Agrobacterium tumefaciens, was discovered and in the early 1970s the tumor inducing agent was found to be a DNA plasmid called the Ti plasmid
By removing the genes in the plasmid that caused the tumor and adding in novel genes researchers were able to infect plants with A. tumefaciens and let the bacteria insert their chosen DNA into the genomes of the plants
By removing the genes in the plasmid that caused the tumor and adding in novel genes researchers were able to infect plants with A. tumefaciens and let the bacteria insert their chosen DNA into the genomes of the plants
Genetic engineering has been used to produce proteins derived from humans and other sources in organisms that normally cannot synthesise these proteins. Bacteria synthesising human insulin were developed in 1979, being used as a treatment for the first time in 1982.[48] In 1988 the first human antibodies were produced in plants.[In 1997avidin, an egg protein, was expressed in a plant with the intention of extracting, purifying and selling it.[49] The first transgenic livestock were produced in 1985,[50] by micro injecting foreign DNA into rabbits, sheep and pigs eggs.[51] The first animal to synthesise transgenic proteins in their milk were mice,[52] engineered to produce human tissue plasminogen activator.[53] This technology has now been applied to other sheep, pigs, cows and other livestock.[52]
With the discovery of microRNA in 1993 came the possibility of using RNA interference to silence an organisms endogenous genes. Craig C. Mello and Andrew Fire discovered a silencing effect in 1998 through injection of double stranded RNA into C. Elegans . Using genetic engineering the microRNA can be expressed long term, permanently silencing the target genes. In 2002 stable gene silencing was induced in mammalian cells,[and in 2005 this was accomplished in a whole mouse.[In 2007 papers were released where insect and nematode genes that formed microRNA were put into plants, resulting in gene silencing of the pest when they ingested the transgenic plant.[58]
The development of genetic engineering technology led to concerns in the scientific community about potential risks. The development of a regulatory framework concerning genetic engineering began in 1975, at Asilomar, California. The Asilomar meeting recommended a set of guidelines regarding the cautious use of recombinant technology and any products resulting from that technology.[30] The Asilomar recommendations were voluntary, but in 1976 the US National Institute of Health (NIH) formed a recombinant DNA advisory committee.[31] This was followed by other regulatory offices (the United States Department of Agriculture (USDA), Environmental Protection Agency (EPA) and Food and Drug Administration (FDA)), effectively making all recombinant DNA research tightly regulated in the USA.[In 1982 the Organization for Economic Co-operation and Development (OECD) released a report into the potential hazards of releasing genetically modified organisms into the environment as the first transgenic plants were being developed.[33] As the technology improved and genetically organisms moved from model organisms to potential commercial products the USA established a committee at theOffice of Science and Technology (OSTP) to develop mechanisms to regulate the developing technology.[32] In 1986 the OSTP assigned regulatory approval of genetically modified plants in the US to the USDA, FDA and EPA.[34] In the late 1980s and early 1990s, guidance on assessing the safety of genetically engineered plants and food emerged from organizations including the FAO and WHO.[35][36][37
WHO (1987): Principles for the Safety Assessment of Food Additives and Contaminants in Food, Environmental Health Criteria 70. World Health Organization, Geneva
Jump up^ WHO (1991): Strategies for assessing the safety of foods produced by biotechnology, Report of a Joint FAO/WHO Consultation. World Health Organization, Geneva
Jump up^ WHO (1993): Health aspects of marker genes in genetically modified plants, Report of a WHO Workshop. World Health Organization, Geneva
Jump up^ WHO (1995): Application of the principle of substantial equivalence to the safety evaluation of foods or food components from plants derived by modern biotechnology, Report of a WHO Workshop. World Health Organization, Geneva
n 1976 Genentech, the first genetic engineering company was founded by Herbert Boyer and Robert Swanson and a year later and the company produced a human protein (somatostatin) in E.coli. Genentech announced the production of genetically engineered human insulin in 1978.[59] In 1980, the U.S. Supreme Court in the Diamond v. Chakrabarty case ruled that genetically altered life could be patented.[60] The insulin produced by bacteria, branded humulin, was approved for release by the Food and Drug Administration in 1982.[61] In 1983, a biotech company, Advanced Genetic Sciences (AGS) applied for U.S. government authorization to perform field tests with the ice-minus strain of P. syringae to protect crops from frost, but environmental groups and protestors delayed the field tests for four years with legal challenges.[62] In 1987, the ice-minus strain of P. syringae became the first genetically modified organism (GMO) to be released into the environment[63] when a strawberry field and a potato field in California were sprayed with it.[64] Both test fields were attacked by activist groups the night before the tests occurred: "The world's first trial site attracted the world's first field trasher".[63]
The first field trials of genetically engineered plants occurred in France and the USA in 1986, tobacco plants were engineered to be resistant to herbicides.[65] The People’s Republic of China was the first country to commercialize transgenic plants, introducing a virus-resistant tobacco in 1992.[66] In 1994 Calgene attained approval to commercially release the Flavr Savr tomato, a tomato engineered to have a longer shelf life.[67] In 1994, the European Union approved tobacco engineered to be resistant to the herbicidebromoxynil, making it the first genetically engineered crop commercialized in Europe.[68] In 1995, Bt Potato was approved safe by the Environmental Protection Agency, after having been approved by the FDA, making it the first pesticide producing crop to be approved in the USA.[69] By 2010, according to the annual ISAAA brief: "While 29 countries planted commercialized biotech crops in 2010, an additional 31 countries, totaling 60 have granted regulatory approvals for biotech crops for import for food and feed use and for release into the environment since 1996.... A total of 1,045 approvals have been granted for 196 events (NB: an "event" is a specific genetic modification in a specific species) for 25 crops. Thus, biotech crops are accepted for import for food and feed use and for release into the environment in 60 countries, including major food importing countries like Japan, which do not plant biotech crops. Of the 60 countries that have granted approvals for biotech crops, USA tops the list followed by Japan, Canada, Mexico, South Korea, Australia, the Philippines, New Zealand, the European Union, and Taiwan. Maize has the most events approved (65) followed by cotton (39), canola (15), potato and soybean (14 each). The event that has received regulatory approval in most countries is herbicide tolerant soybean event GTS-40-3-2 with 25 approvals (EU=27 counted as 1 approval only), followed by insect resistant maize MON810 with 23 approvals, herbicide tolerant maize NK603 with 22 approvals each, and insect resistant cotton (MON1445) with 14 approvals worldwide."
strand that contains the same series of nitrogenous bases regardless from which direction the strand is analyzed.