This document provides an overview of genetic diseases and inborn errors of metabolism. It discusses genetic disorders, including that most are rare and can be hereditary or caused by new mutations. Inborn errors of metabolism are caused by defects in enzyme-coding genes. The document also examines genetic epidemiology, cardiovascular disease, cancer, chronic diseases, environmental teratogens, genetic diseases, ethical issues in genetic testing, genetic research, research questions for genetic disorders, the aims and scope of genetic research, findings from genetic studies, and concludes that genetic testing will play a greater role in healthcare.
2. Content:
1.Introduction
2.Overview of topics
Environmental Teratogens
Genetic Diseases
Ethical Issue in genetic testing
Genetic Research : an overview
3.Research questions
4.Aim and scope
5.Findings
6.Conclusion
7.Reference
3. Introduction to Genetic Disorder:
A genetic disorder is a genetic problem caused by one or more abnormalities
formed in the genome. Most genetic disorders are quite rare and affect one person
in every several thousands or millions.
Genetic disorders may be hereditary, meaning that they are passed down from the
parents' genes. In other genetic disorders, defects may be caused by
new mutations or changes to the DNA.
4. Introduction to Inborn errors:
Inborn errors of metabolism comprise a large class of genetic disease involving
disorders of metabolism.
The majority are due to defects of single genes that code for enzymes that
facilitate conversion of various substances (substrates) into others (products).
In most of the disorders, problems arise due to accumulation of substances which
are toxic or interfere with normal function, or to the effects of reduced ability to
synthesize essential compounds.
Inborn errors of metabolism is also referred to as Congenital metabolic diseases
Or Inherited Metabolic diseases.
5. Overview of Genetic diseases:
Genetic epidemiology is the study of the role of genetic factors in determining health
and disease in families and in populations, and the interplay of such genetic factors
with environmental factors.
Genetic epidemiology seeks to derive a statistical and quantitative analysis of how
genetics work in large groups.
6. Cardiovascular disease:
Cardiovascular disease generally refers to
conditions that involve narrowed or blocked blood
vessels that can lead to a heart attack, chest pain
(angina) or stroke. Other heart conditions, such as
those that affect your heart's muscle, valves or
rhythm, also are considered forms of heart
disease.
8. Treatment for cardiovascular
disease
1. lifestyle adaptations, such as weight
control, exercise, quitting smoking,
and dietary changes.
2. medication, for example, to reduce
LDL cholesterol.
3. surgery, such as coronary artery
bypass grafting (CABG)
4. cardiac rehabilitation, including
exercise and counseling.
Cure for cardiovascular
disease
There is some evidence that
normalizing high blood pressure and
lowering cholesterol to very low
levels will partially reverse plaques in
the coronary arteries.
9. Cancer
1. Cancer is a group of diseases involving abnormal cell growth with the potential to
invade or spread to other parts of the body. These contrast with benign tumors,
which do not spread.
2. It describes the disease that results when cellular changes cause the uncontrolled
growth and division of cells.
Most of the body's cells have specific functions and fixed lifespans. While it may
sound like a bad thing, cell death is part of a natural and beneficial phenomenon
called apoptosis.
10. A cell receives instructions to die so that the body can replace it with a newer cell
that functions better. Cancerous cells lack the components that instruct them to
stop dividing and to die.
As a result, they build up in the body, using oxygen and nutrients that would
usually nourish other cells. Cancerous cells can form tumors, impair the immune
system and cause other changes that prevent the body from functioning regularly.
Cancerous cells may appear in one area, then spread via the lymph nodes. These
are clusters of immune cells located throughout the body.
11. Types of Cancer:
Malignant tumors
Cells tend not to spread
Most grow slowly
Do not invade nearby tissue
Do not metastasize (spread) to other parts of the
body
Tend to have clear boundaries
Under a pathologist's microscope, shape,
chromosomes, and DNA of cells appear normal
Do not secrete hormones or other substances (an
exception: pheochromocytomas of the adrenal
gland)
May not require treatment if not health-threatening
Unlikely to recur if removed or require further
treatment such as radiation or chemotherapy.
Example: breast, intestines, lungs, reproductive
organs ,blood, skin.
Benign tumors
Cells can spread
Usually grow fairly rapidly
Often invade basal membrane that surrounds
nearby healthy tissue
Can spread via bloodstream or lymphatic
system, or by sending "fingers" into nearby
tissue
May recur after removal, sometimes in areas
other the original site
Cells have abnormal chromosomes and DNA
characterized by large, dark nuclei; may have
abnormal shape
Can secrete substances that cause fatigue and
weight loss (paraneoplastic syndrome)
May require aggressive treatment, including
surgery, radiation, chemotherapy, and
immunotherapy medications
Example: Fibroids in uterus, lipomas
12.
13. Types of cancers also include:
Bladder Cancer.
Breast Cancer.
Colorectal Cancer.
Kidney Cancer.
Lung Cancer - Non-Small Cell.
Lymphoma - Non-Hodgkin.
Melanoma.
Oral and Oropharyngeal Cancer.
15. Environmental teratogens:
The largest category of malformations, 65% falls into the group of those with an
unknown cause(s). Purely genetic causes of malformations (autosomal and
cytogenetic), estimated to produce 20 to 25% of all human malformations,
comprise the largest group of congenital malformations with known etiology.
Although environmental causes of human malformations account for 10% or fewer
of malformations, most of these environmentally induced malformations are
related to maternal disease states.
Fewer than 1% of all human malformations are related to drug exposure, chemicals,
or radiation, but studies of environmentally induced malformations are important
because they may teach us how to predict and test for teratogenicity, understand
the mechanisms of teratogenesis from all etiologies, and provide a means by which
human malformations can be prevented.
16. Genetic diseases:
A genetic disorder is a genetic problem caused by one or more abnormalities
formed in the genome. Most genetic disorders are quite rare and affect one person
in every several thousands or millions.
Genetic disorders may be hereditary, meaning that they are passed down from the
parents' genes. In other genetic disorders, defects may be caused by
new mutations or changes to the DNA. In such cases, the defect will only be passed
down if it occurs in the germline.
17. Ethical Issues in Genetic Testing
Genetic testing is poised to play an increasing role in the practice of obstetrics and
gynecology. To assure patients of the highest quality of care, physicians should
become familiar with the currently available array of genetic tests and the tests'
limitations.
Clinicians should be able to identify patients within their practices who are candidates
for genetic testing. Candidates will include patients who are pregnant or considering
pregnancy and are at risk for giving birth to affected children as well as gynecology
patients who, for example, may have or be predisposed to certain types of cancer.
The purpose of this Committee Opinion is to review some of the ethical issues related
to genetic testing and provide guidelines for the appropriate use of genetic tests by
obstetrician–gynecologists. Expert consultation and referral are likely to be needed
when obstetrician–gynecologists are confronted with these issues.
19. Genetic Research: An Overview
Genetic research on human subjects can raise a number of distinctive problems. One
common problem is that researchers (and sometimes experimental subjects) may
acquire genetic information that also pertains to relatives who have not consented to
any investigation and need not be made aware of its results.
Genetic research may also raise distinctive ethical problems if it ‘medicalizes’
characteristics previously accepted as natural variation.
Genetic research has progressed significantly over the past few decades to
improve human health. This progress however brings about a number of ethical
concerns.
we explore revisited issues about consent, privacy, and return of results and incidental
findings in population biobanks and genetic testing; misuse of genetic information in
the contexts of immigration, employment, and insurance; and the commodification
and patentability of genetic information.
20. Research question
1. Establishing that there is a genetic component to the disorder.
2. Establishing the relative size of that genetic effect in relation to other sources of
variation in disease risk (environmental effects such as intrauterine environment,
physical and chemical effects as well as behavioral and social aspects).
3. Identifying the gene(s) responsible for the genetic component.
These research methodologies can be assessed through either family or
population studies.
21. Aim and Scope For Genetic Disorders:
Chromosome Abnormalities
Medical Genetics
Clinical Genetics
Gene therapy
Cancer Cytogenetics
DNA damage repair
Genealogical Tracing
Hereditary genetic disorders
Types of mutations
Abnormal gene expression
Epigenetics
Gene mapping with three-point crosses
Forward and Reverse genetics
Genetic linkage and genetic maps
Human Genetics
Plant genetics
Human genetic disorders
Plant genetic disorders
Mutation rates
Genetic disorder therapies
Genetic polymorphisms
Gene inheritance and Transmission
Gene expression and Regulation
Annotation of the genomes of human
Genetics of Infectious Diseases
Genetic alterations underlying complex human
diseases
Transposes: jumping genes
22. Findings
The genetic underpinnings of ALS are poorly understood, so the discovery of genetic
associations always has exciting implications for new areas of research.
Fusion genes are created when a chromosomal mutation causes two otherwise healthy
genes to join together. For many years, it was believed that fusion genes were
implicated only in blood and bone marrow cancers like leukemia, but a recent study by
researchers at the Sahlgrenska Academy at the University of Gothenburg, Sweden found
that the MYB-NFIB fusion gene was found in 100% of adenoid cystic carcinomas — a
glandular cancer usually fond in the head, neck, and breasts.
By collaborating with The 1000 Genomes Project, an international team of scientists led
by researchers at The Sanger Institute was able to conduct a massive genetic screen
(eventually involving over 50,000 people) to identify a third genetic link: MCF2L.
23. Cardiff University's Julie Williams recently led the world's largest-ever genetic
investigation of Alzheimer's, screening around 20,000 people with the disease and
40,000 unaffected individuals to identify five new Alzheimer's-linked genes,
doubling the total number of genes known to increase the risk of developing
Alzheimer's.
The World Health Organization estimates that heart diseases claim upwards of 17
million lives a year, making them the world's deadliest class of diseases. Just like
lung cancer, while environmental factors like smoking and drinking certainly put
people at higher risk of developing cardiovascular diseases, there is believed to be
a strong genetic component to them as well.
Interestingly, many of the newly identified genes have no known relation to
previously identified cardiovascular risk factors like cholesterol or hypertension,
which suggests that there are promising therapeutic mechanisms yet to be
discovered.
24. Conclusion
Genetic testing is poised to play a greater and greater role in the practice of obstetrics
and gynecology. To assure patients of the highest quality of care, physicians should be
familiar with the currently available array of genetic tests, as well as with their
limitations.
They also should be aware of the untoward consequences their patients might sustain
because of a genetic diagnosis. The physician should work to minimize those
consequences. Genetic information is unique in being shared by a family.
Physicians should inform their patients of that fact and help them to prepare for
dealing with their results, including considering disclosure to their biologic family. If
the genetic information could potentially benefit family members (e.g, allow them to
improve their own prognosis), physicians should guide their patients toward voluntary
disclosure while assiduously guarding their right to confidentiality.
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