1. Pedigrees

2. Using Pedigrees
Humans cannot be selectively bred like Mendel’s pea plants
Geneticists use pedigrees to:
Study human genetic disorders
Predict the probability that a person has or carries a specific trait

3. Pedigree Symbols male female mating (square on left)
children (birth order left to right)

4. Pedigree Symbols carrier (has a recessive gene for the trait)
non-affected (does not have trait)
carrier (has a recessive gene for the trait)
affected (has the trait)

5. Pedigree Symbols I II III
Each generation is labeled with a roman numeral
Individuals are labeled from left to right starting with 1 I II
III 1 2 3 5 6 7 4 9 8 10 11 12 13 14

6. Typical Pedigree Types
autosomal dominant
autosomal recessive
sex linked recessive
sex linked dominant
Mitochondrial inheritance

7. Autosomal Dominant easiest patterns to recognize one parent affected
½ or all of the children affected
will usually have at least one affected in each generation
Heterozygous for the trait
Homozygous for the trait

8. Autosomal Recessive
Both parents appear to be non-affected but can produce affected children
Affected children are homozygous recessive
Parents can be shown two ways

9. X Linked Recessive The father is affected (has the trait)
His daughters can be carriers for the trait
Only the sons express the trait

10. X Linked Dominant The father is affected (has the trait)
All of his daughters are affected (have the trait)
None of the sons express the trait

11. Mitochondrial Inheritance
All of the children of an affected female are affected (have the trait)
None of the children of an affected male will have the trait

12. Russian Royal Families
Prince Albert
Queen Victoria

13. Russian Royal Families
Instead of numbering them traditionally, start at the top left with #1 and work your way across and then down
Number all of the individuals in the pedigree chart.

14. Russian Royal Families
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

15. Which numbers are the children of 7 and 8?
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

16. Color all hemophilia carriers blue
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31
What do all the carriers have in common?

17. Color all hemophiliacs red
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31
What do the affected have in common?

18. What relation is number 22 to Queen Victoria?
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31
Do you think Alexis has hemophilia?

19. Color all non-affected individuals yellow
Prince Albert________
Queen Victoria______ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 23 22 24 25 26 27 28 29 30 44 45 46 41 42 43 38 39 40 34 35 36 37 32 33 31

20. Complete the assignment by circling the right answer choice then label individuals mentioned in the story.
Turn in to the tray when finished