1. 5.2 Human Genetic Disorders
Human Heredity
5.2 Human Genetic Disorders

2. POINT > Define a gene in simple terms
POINT > Define and describe genetic mutations
POINT > Distinguish between gene and chromosomal mutations
POINT > Describe examples of genetic diseases caused by single gene mutations
POINT > Identify human diseases caused by chromosomal mutations
POINT > Explain Pedigree analysis

3. POINT > Define a gene in simple terms
One gene is a sequence of DNA that codes for one protein There are 1000’s of different proteins in a cell
Each protein has an important function in the cell
The DNA sequence in a gene determines the amino acid sequence in a protein
The amino acid sequence of the protein has to be correct! If not...

9. Werewolf

10. POINT > Define and describe genetic mutations
A mutation is a change to the DNA sequence of an organism A gene mutation affects only one gene/one protein A chromosomal mutation affects the number of chromosomes in the cell. This affects many genes

11. POINT > Define and describe genetic mutations
If the DNA is altered, the mutation is passed to daughter cells through mitosis If the mutation occurs in an egg cell or sperm cell, the changes are passed to offspring

12. CHECK:
What is a mutation? What is a gene mutation? What is a chromosomal mutation?

13. The Mummy

14. POINT > Describe human diseases caused by single gene mutations
Cystic fibrosis: a recessive allele carries a mutation that causes mucus to fill the lungs
Difficulty breathing and death are the results of this disease

15. POINT > Describe human diseases caused by single gene mutations
2. Sickle cell anemia: A codominant allele causes some red blood cells to be misshaped
Blood doesn’t carry oxygen as well

16. POINT > Describe human diseases caused by single gene mutations
Hemophilia: A sex-linked (X chromosome) recessive allele causes blood to not clot
Patients have excessive bleeding

17. CHECK:
What kind of allele causes cystic fibrosis? What kind of allele causes sickle cell anemia? What kind of allele causes hemophilia ?

18. Frankenstein monster

19. Varying degrees of mental retardation
POINT > Identify human diseases caused by chromosomal mutations
Down’s syndrome:
1 extra chromosome (#21)
Varying degrees of mental retardation
Many distinct physical characteristics

20. POINT > Identify human diseases caused by chromosomal mutations
Edward’s syndrome
1 extra chromosome (#18)
Major physical abnormalities & mental retardation
~3% of cases result in live birth, median lifespan is days

21. CHECK:
What causes Down’s syndrome? What causes Edwards syndrome?

22. Dracula

23. POINT > Explain pedigree analysis

24. POINT > Explain pedigree analysis
Pedigree analysis is used to trace a disease or trait in a family history

25. POINT > Explain pedigree analysis
Examples of symbols:
Female:
Male:
You must learn the symbols of the pedigree charts before you can start to learn how to interpret it. These are the symbols that represent a male and a female.

26. POINT > Explain pedigree analysis
Examples of symbols:
Married Couple:
Offspring:
These symbols also represent relationships between people. some may have to each other.

27. POINT > Explain pedigree analysis
Empty shape = unaffected
 Carrier. Has allele, but not the disease/trait
 Has the disease/trait

28. Color Blindness About 1 in 10 men have some form of color blindness.
Sex-linked recessive disorder
Can get color blind from nerve damage, or drugs (one drug used to treat arthritis causes color blindness), but most of the time is a genetic disorder. Color blindness is a life long condition, doesn’t impact day to day life that much. Color blind people may not be able to do certain jobs that require seeing color, like a fashion designer or a cook who needs to be able to tell when the meat is done, or an electrician who can’t tell the difference between wire colors that she or he needs to cut

30. Homework:
Read pages
S.A. #1-3 page 155
GRAS pages 72-73
Pedigree analysis Worksheet