1. Human Genetics: Pedigree

2. Genes are pieces of DNA that code for a trait.

3. Example: Codes for hair, eye, skin color

4. Genes are passed from parents to offspring. This is called heredity.

6. Heredity can be studied using a pedigree chart
Heredity can be studied using a pedigree chart. This shows your family history for a particular trait.

7. Pedigree: the record of descent of an animal

8. Males are always represented with a box; females with a circle.

9. Those who carry the trait have the symbol filled in
Those who carry the trait have the symbol filled in. Those who carry it (heterozygous) have half the box filled in.

10. Shaded in- Affected
Left blank- Non Affected

12. Twins/Triplets

13. DD D D dd d d Dd D d Dominant, Dominant Recessive, Recessive

14. Example: Make a pedigree for a father with black hair, a wife without, and three children: one boy, and two girls. All children have black hair

16. Dominant traits show up in every generation, whereas recessive traits do not.

17. Sex-linked traits deal with one’s gender
Sex-linked traits deal with one’s gender. These are most-often found in males.

18. Is the trait in this pedigree dominant or recessive? Sex-linked or not?

19. Step One: Create 3 GenerationsII
III

20. Step 2: Start with 3rd Gen first.II
III
You, siblings, step-siblings, cousins

21. Step 3- Add 2nd Gen I II
Parents, step-parents, aunts, uncles
III
You, siblings, step-siblings, cousins

22. Step 4- Add 1st Gen I
Grandparents II
Parents, step-parents, aunts, uncles
III
You, siblings, step-siblings, cousins