RELEVANCE AND IMPLICATIONS
P R E P A R E D B Y : J E N N I F E R C . G R A G E R A , R N
U N I V E R S I T Y O F N O R T H...
THE NORMAL CELL
The Parts of a Cell
 Cells have two main parts, the cytoplasm and the nucleus.
 The cytoplasm surrounds the nucleus, muc...
The Cytoplasm
The cytoplasm contains many organelles. Organelles are like
tiny organs. Each has specific jobs to do within...
The Nucleus
The nucleus plays an important role in heredity and
cell division.
 Heredity is what you "inherit" from your ...
Two Types of Nuclei/Two Types of Cells
 Somatic cells - cells that make up the body
contain the usual 46 chromosomes.
 G...
How Cells Divide?
There are two types of cell division, mitosis and
meiosis.
Mitosis is how somatic cells divide.
Meiosi...
What Makes Cells Divide?
Growth factors in the blood or produced by cells stimulate cells to
divide. Certain genes in the ...
GENES AND CHROMOSOMES
 What Is DNA?
DNA (deoxyribonucleic acid) carries the genetic information in the body’s
cells. DNA ...
CHROMOSOME ABNORMALITIES
A chromosome abnormality reflects an abnormality of chromosome number
or structure. There are man...
b. Structural Abnormalities:
 Deletions: A portion of the chromosome is missing or deleted.
 Duplications: A portion of ...
How do chromosome abnormalities
happen?
 Chromosome abnormalities usually occur when
there is an error in cell division. ...
Other factors that can increase the risk of
chromosome abnormalities
 Maternal Age: Women are born with all the eggs they...
GENETIC DISORDERS
A. SINGLE GENE DISORDER
A single gene disorder is the result of a single mutated gene. Over 4000
human d...
Definition of Terms
 Autosomal: the gene responsible for the phenotype is
located on one of the 22 pairs of autosomes (no...
Non-X-linked (Autosomal)
Dominant Inheritance
Non–X-Linked (Autosomal)
Recessive Inheritance
X- linked Inheritance
(Dominant Disorder)
X-linked Inheritance
(Recessive Disorder)
Prevalence of some single gene disorders
Autosomal dominant
 Familial hypercholesterolemia 1 in 500
 Polycystic kidney d...
Y-linked Inheritance
Mitochondrial Inheritance
B. MULTIFACTORIAL AND POLYGENIC
(COMPLEX) DISORDER
 Genetic disorders may also be complex, multifactorial, or
polygenic, ...
Examples of Multifactorial and Polygenic (Complex)
Disorders:
 asthma
 autoimmune diseases such as multiple sclerosis
 ...
TESTING FOR CHROMOSOMAL AND
GENETIC ABNORMALITIES
 A person's chromosomes and genes can be evaluated
by analyzing a sampl...
PREVENTION
 Although chromosomal abnormalities cannot be
corrected, some birth defects can sometimes be
prevented (for ex...
 Did you know…
Not all gene abnormalities are purely harmful – the
gene that causes sickle cell disease also provides
pro...
"All human disease is genetic in origin."
Paul Berg was awarded one-half of the 1980 Nobel
Prize in Chemistry. He was reco...
THANK YOU!!!
Genes, Chromosomes, and Genetic Code: Relevance and Implications
Genes, Chromosomes, and Genetic Code: Relevance and Implications
Genes, Chromosomes, and Genetic Code: Relevance and Implications
Genes, Chromosomes, and Genetic Code: Relevance and Implications
Genes, Chromosomes, and Genetic Code: Relevance and Implications
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Genes, Chromosomes, and Genetic Code: Relevance and Implications

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Genes are the thing that determines your unique traits from the inside out. They play an important role in your overall health but they can also make you more susceptible for certain health problems and diseases, in the first place those that run in your family. Most diseases are a result of a combination of multiple factors including dietary, lifestyle and environmental factors. However, it is also possible to develop health problems exclusively due to genetic abnormalities and mutations.

Published in: Health & Medicine, Technology
  • id like to know the common known chromosomal abnormalities most women experienced delivering 30 years and up.Aside from old age, Is chromosomal abnormalities associated with race or culture? If so what are those most common CA?
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Genes, Chromosomes, and Genetic Code: Relevance and Implications

  1. 1. RELEVANCE AND IMPLICATIONS P R E P A R E D B Y : J E N N I F E R C . G R A G E R A , R N U N I V E R S I T Y O F N O R T H E R N P H I L I P P I N E S M A S T E R O F A R T S I N N U R S I N G GENES, CHROMOSOMES, AND GENETIC CODE:
  2. 2. THE NORMAL CELL
  3. 3. The Parts of a Cell  Cells have two main parts, the cytoplasm and the nucleus.  The cytoplasm surrounds the nucleus, much the way the white surrounds the yolk in an egg.  The nucleus is separated from the cytoplasm by the nuclear membrane.  The cell membrane surrounds the cytoplasm.
  4. 4. The Cytoplasm The cytoplasm contains many organelles. Organelles are like tiny organs. Each has specific jobs to do within the cell. Some of the important organelles are:  The endoplasmic reticulum helps make protein.  The golgi apparatus helps move materials out of the cells in which they are made.  Mitochondria make energy needed for cell function.  Lysosomes digest substances brought into the cell.  The substance surrounding organelles within the cytoplasm is known as the cytosol.
  5. 5. The Nucleus The nucleus plays an important role in heredity and cell division.  Heredity is what you "inherit" from your parents through your genes. (Genes are found in chromosomes.)  Cell division is how new cells are made.
  6. 6. Two Types of Nuclei/Two Types of Cells  Somatic cells - cells that make up the body contain the usual 46 chromosomes.  Gametes - sex cells (the egg and sperm) contain only 23 chromosomes. That's half the number found in somatic cells.
  7. 7. How Cells Divide? There are two types of cell division, mitosis and meiosis. Mitosis is how somatic cells divide. Meiosis is how sex cells divide.
  8. 8. What Makes Cells Divide? Growth factors in the blood or produced by cells stimulate cells to divide. Certain genes in the cell then turn the cell "on" so that division can happen. After the cell has divided, other genes turn the cell "off" again. The chain of events is as follows:  Growth factors attach to the cell membrane. They turn "on" messenger substances within the cell.  The messengers send signals to the nucleus of the cell.  Genes in the nucleus turn "on" the division process.  The DNA in the nucleus replicates (doubles).  The cell divides.  Genes in the nucleus turn the cell "off." Changes (mutations) in the genes can affect their ability to turn the cells "on" or "off." This can cause uncontrolled cell growth and cancer.
  9. 9. GENES AND CHROMOSOMES  What Is DNA? DNA (deoxyribonucleic acid) carries the genetic information in the body’s cells. DNA is made up of four similar chemicals (called bases and abbreviated A, T, C, and G) that are repeated over and over in pairs.  What Is a Gene? A gene is a distinct portion of a cell’s DNA. Genes are coded instructions for making everything the body needs, especially proteins. Human beings have about 25,000 genes. Researchers have discovered what some of our genes do, and have found some that are associated with disorders (such as cystic fibrosis or Huntington’s disease). There are, though, many genes whose functions are still unknown.  What Are Chromosomes? Genes are packaged in bundles called chromosomes. Humans have 23 pairs of chromosomes (for a total of 46). Of those, 1 pair is the sex chromosomes (determines whether you are male or female, plus some other body characteristics), and the other 22 pairs are autosomal chromosomes (determine the rest of the body’s makeup).
  10. 10. CHROMOSOME ABNORMALITIES A chromosome abnormality reflects an abnormality of chromosome number or structure. There are many types of chromosome abnormalities. However, they can be organized into two basic groups: a. Numerical Abnormalities  When an individual is missing either a chromosome from a pair (monosomy) or has more than two chromosomes of a pair (trisomy).  An example of a condition caused by numerical abnormalities is Down Syndrome, also known as Trisomy 21 (an individual with Down Syndrome has three copies of chromosome 21, rather than two).  Turner Syndrome is an example of monosomy, where the individual - in this case a female - is born with only one sex chromosome, an X.
  11. 11. b. Structural Abnormalities:  Deletions: A portion of the chromosome is missing or deleted.  Duplications: A portion of the chromosome is duplicated, resulting in extra genetic material.  Translocations: Segments from two different chromosomes are exchanged.  Inversions: A portion of the chromosome has broken off, turned upside down and reattached, therefore the genetic material is inverted.  Insertions: A portion of a chromosome has broken off and attaches to another chromosome.
  12. 12. How do chromosome abnormalities happen?  Chromosome abnormalities usually occur when there is an error in cell division. There are two kinds of cell division, mitosis and meiosis.  In both processes, the correct number of chromosomes is supposed to end up in the resulting cells. However, errors in cell division can result in cells with too few or too many copies of a chromosome. Errors can also occur when the chromosomes are being duplicated.
  13. 13. Other factors that can increase the risk of chromosome abnormalities  Maternal Age: Women are born with all the eggs they will ever have. Therefore, when a woman is 30 years old, so are her eggs. Some researchers believe that errors can crop up in the eggs' genetic material as they age over time. Therefore, older women are more at risk of giving birth to babies with chromosome abnormalities than younger women. Since men produce new sperm throughout their life, paternal age does not increase risk of chromosome abnormalities.  Environment: Although there is no conclusive evidence that specific environmental factors cause chromosome abnormalities, it is still a possibility that the environment may play a role in the occurence of genetic errors.
  14. 14. GENETIC DISORDERS A. SINGLE GENE DISORDER A single gene disorder is the result of a single mutated gene. Over 4000 human diseases are caused by single gene defects. Single gene disorders can be passed on to subsequent generations in several ways.  Non-X-linked Inheritance/Autosomal (Dominant and Recessive Disorders)  X-Linked Inheritance (Dominant and Recessive Disorders)  Y-Linked Inheritance  Mitochondrial Inheritance
  15. 15. Definition of Terms  Autosomal: the gene responsible for the phenotype is located on one of the 22 pairs of autosomes (non-sex determining chromosomes).  X-linked: the gene that encodes for the trait is located on the X chromosome.  Dominant: conditions that are manifest in heterozygotes (individuals with just one copy of the mutant allele).  Recessive: conditions are only manifest in individuals who have two copies of the mutant allele (are homozygous).
  16. 16. Non-X-linked (Autosomal) Dominant Inheritance
  17. 17. Non–X-Linked (Autosomal) Recessive Inheritance
  18. 18. X- linked Inheritance (Dominant Disorder)
  19. 19. X-linked Inheritance (Recessive Disorder)
  20. 20. Prevalence of some single gene disorders Autosomal dominant  Familial hypercholesterolemia 1 in 500  Polycystic kidney disease 1 in 1250  Neurofibromatosis type I 1 in 2,500  Hereditary spherocytosis 1 in 5,000  Marfan syndrome 1 in 4,000  Huntington's disease 1 in 15,000 Autosomal recessive  Sickle cell anaemia 1 in 625  Cystic fibrosis 1 in 2,000  Tay-Sachs disease 1 in 3,000  Phenylketonuria 1 in 12,000  Mucopolysaccharidoses 1 in 25,000  Lysosomal acid lipase deficiency 1 in 40,000  Glycogen storage diseases 1 in 50,000  Galactosemia 1 in 57,000 X-linked  Duchenne muscular dystrophy 1 in 7,000  Hemophilia 1 in 10,000
  21. 21. Y-linked Inheritance
  22. 22. Mitochondrial Inheritance
  23. 23. B. MULTIFACTORIAL AND POLYGENIC (COMPLEX) DISORDER  Genetic disorders may also be complex, multifactorial, or polygenic, meaning they are likely associated with the effects of multiple genes in combination with lifestyles and environmental factors.  Although complex disorders often cluster in families, they do not have a clear-cut pattern of inheritance. This makes it difficult to determine a person’s risk of inheriting or passing on these disorders.
  24. 24. Examples of Multifactorial and Polygenic (Complex) Disorders:  asthma  autoimmune diseases such as multiple sclerosis  cancers  cleft palate  diabetes  heart disease  hypertension  inflammatory bowel disease  mental retardation  mood disorder  obesity  refractive error
  25. 25. TESTING FOR CHROMOSOMAL AND GENETIC ABNORMALITIES  A person's chromosomes and genes can be evaluated by analyzing a sample of blood.  In addition, doctors can use cells from amniocentesis or chorionic villus sampling to detect certain chromosomal or genetic abnormalities in a fetus.  If the fetus has an abnormality, further tests may be done to detect specific birth defects.
  26. 26. PREVENTION  Although chromosomal abnormalities cannot be corrected, some birth defects can sometimes be prevented (for example, taking folate [folic acid] to prevent neural tube defects or screening parents for carrier status of certain genetic abnormalities).
  27. 27.  Did you know… Not all gene abnormalities are purely harmful – the gene that causes sickle cell disease also provides protection against malaria.
  28. 28. "All human disease is genetic in origin." Paul Berg was awarded one-half of the 1980 Nobel Prize in Chemistry. He was recognized for "his fundamental studies of the biochemistry of nucleic acids, with particular regard to recombinant DNA“.
  29. 29. THANK YOU!!!

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