Pedigrees

1. Pedigrees OGT

2. What Are They? Pedigreesarefamily records that show how traits are passed through many generations

3. Pedigrees are diagrams that show family inheritance patterns for specific trait male symbol = female symbol =

4. affected male = affected female = carrier =

5. Parents linked with horizontal lines Offspring linked with vertical lines

6. As usual - traits can be either dominantorrecessive

7. Dominant traits are seen in every generation and Dominant traits affect an equal percentage of malesand females

8. Marfan’s Syndrome • This is a dominant genetic disorder that affects connective tissue so people with it have longer and thinner fingers M = dominant allele m = recessive allele

11. Recessive traits will often skip a generation but Recessive traits also affect an equal percentage of males and female

12. Albinism • People with albinism have little or no pigment in their skin, hair, etc. A = dominant allele a = recessive allele

15. Genetic Counseling Activity

16. Begin You are a Genetic Counselor You will be determining the possibility of children inheriting a genetic disorder

17. You are given the family history which indicates if a particular disorder is dominant or recessive 1. Draw a Punnett Square to determine odds of children inheriting the disease 2. Complete a Pedigree diagram

18. Case 1 - dominance Both parents are heterozygous E =normal night vision e = night blindness

19. E = normal vision e = night blindness

20. EE = normal Ee = normal ee = night blind

21. Case 2 - recessiveness Both parents are heterozygous R = normal skull r = pointed skull

22. R = normal skull r = pointed skull

23. RR = normal Rr = normal carrier rr = pointed

24. End Pedigrees - Autosomal