1. Today’s Date Here
Objective Here!

2. Brainteaser
What is the center of gravity?

3. Human Genetic Disorders
And Karyotypes

4. What is a Karotype?
A picture of the collection of chromosomes found in an individual’s cells
Tells you the chromosome # of
an organism
46 in humans
Tells you the sex of an organism
XX = Female XY = Male
Can indicate whether or not a chromosomal abnormality is present.

5. Karyotype
MALE
FEMALE

6. Chromosomal Abnormalities
Monosomy
Trisomy
the condition in which a diploid cell is missing a chromosome
the condition in which a diploid cell has an extra chromosome

7. Nondisjunction Disorders
Caused by an abnormal number of a particular chromosome

8. Types of Chromosomal Abnormalities
Down Syndrome
Extra 21st Chromosome
Symptoms:
Distinctive shaped eyes
Cognitive heart abnormalities
Simian folds
Below average cognitive ability
Protruding tongue
Short limbs

9. Types of Chromosomal Abnormalities
Turner’s Symdrome
1 X chromosome and no match
Symptoms
Short stature
Webbed neck
Broad chest
Non-functioning ovaries
sterility

10. Types of Chromosomal Abnormalities
Klienfelter’s Syndrome
2 X chromosomes and 1 Y
Most common chromosomal abnormality
Symptoms
Underdeveloped male sex characteristics
Reduced fertility
Slightly feminime characteristics
Potential language impariment

11. Autosomal Recessive Disorders
Requires the inheritance of two recessive alleles
Error found on chromosomes

12. Cystic Fibrosis (CF) Monogenic
Cause: deletion of only 3 bases on chromosome 7
Fluid in lungs, potential respiratory failure
Common among Caucasians…1 in 20 are carriers
Therefore is it dominant or recessive?

13. Sickle Cell Anemia
An inherited, chronic disease in which the red blood cells, normally disc-shaped, become crescent shaped. As a result, they function abnormally and cause small blood clots. These clots give rise to recurrent painful episodes called "sickle cell pain crises".

14. Albinism
Inability to make melanin which gives pigmentation to hair, eyes, and skin
Mutation in the tyrosinase gene on chromosome #11
Tyrosinase is an enzyme that functions in the production of melanin
Is it monogenic or chromosomal?

15. Phenylketonuria (PKU)
One of the most common causes of mental retardation
Mutation in gene for the enzyme phenylalanine hydroxylase on chromosome #12
This enzyme converts the amino acid phenylalanine to the amino acid tyrosine

16. Phenylketonuria or PKU
People with PKU cannot consume any product that contains aspartame.
PKU is a metabolic disorder that results when the PKU gene is inherited from both parents (recessive or dominant? Monogenic or chromosomal?)
Caused by a deficiency of an enzyme which is necessary for proper metabolism of an amino acid called phenylalanine.

17. Tay-Sachs disease Monogenic, autosomal recessive
Central nervous system degrades, ultimately causing death.
Most common among people of Jewish, eastern Europe descent.
About 1/30 American Jews are carriers of Tay-Sachs disease

18. Autosomal Dominant Disorders
Require the inheritance of only one copy of the allele
Found on chromosomes

19. Achondroplasia The most common form of dwarfism
1/25,000 births result in achondroplasia
Caused by a mutation in the gene for the Fibroblast growth factor receptor 3 protein
This protein functions in normal bone growth
This gene is found on chromosome #4

20. Marfan Syndrome
People with Marfan characteristically are tall with very long limbs and fingers
It is believed that Abraham Lincoln had Marfan Syndrome
Many times people do not know they have the disease and yet are susceptible to aortic rupture
1/5,000 people in the US have Marfan Syndrome
Olympic star volleyball player Flo Hyman died of aortic rupture in Florida State University basketball player Ronaldo Pierce died of aortic rupture in Both had Marfan Syndrome.

21. Huntington’s Disease
Huntington's disease (HD) is an inherited, degenerative brain disorder which results in an eventual loss of both mental and physical control. The disease is also known as Huntington's chorea. Chorea means "dance-like movements" and refers to the uncontrolled motions often associated with the disease.

22. X-Linked Recessive Females have to inherit two copies of the gene
Males have to inherit one copy on the X from their mother

23. Hemophilia, the royal disease
Hemophilia is the oldest known hereditary bleeding disorder.
Caused by a recessive gene on the X chromosome.
There are about 20,000 hemophilia patients in the United States.
One can bleed to death with small cuts.
The severity of hemophilia is related to the amount of the clotting factor in the blood. About 70% of hemophilia patients have less than one percent of the normal amount and, thus, have severe hemophilia.

24. X-linked Inheritance pedigree chart

25. Hemophilia
About 18,000 people (almost all male) in the US have hemophilia
400 babies in the US each year are born with hemophilia
In the 1980’s approximately 10,000 children were infected with HIV because of transfusions for hemophilia
With proper treatment, hemophiliacs can live a normal life

26. Fragile X Syndrome Most common cause of genetic mental impairment
Mutation in the Fragile X Mental retardation protein believed to help brain cells develop & function normally

27. Fragile X Syndrome
In the promoter region for the FMR1 gene, there are CGG repeats
In the normal gene there are 6 – 40 repeats
In the abnormal gene there may be hundreds of repeats
The more CGG is repeated the more severe the disease
Heterozygous females make enough FMR to have normal intelligence
1/2000 males have Fragile X; 1/4,000 females

28. Fragile X