Let’s Review- Harry Potter Genetics

1. Let’s Review- Harry Potter Genetics

2. Question 1 • Harry has dark brown hair like his father, but his mom had red hair. Using the genotypes of B and b, what possible genotypes does each of the Potters have? • The phenotypes of the Potters are: • James Potter- • Lily Potter- • Harry Potter-

3. Using the genotypes of BB, Bb, bb, what are possible genotypes for Harry’s parents?Mom could be (she has red hair)Dad could be (he has dark brown hair) Mom could be bb Dad could be BB or Bb

4. Given the punnet squares for the parents, the only possible genotype for Harry is Bb

5. Question 2: Harry marries Ginny who has red hair. What are the possible Genotypes of their children’s hair?

6. First: what are the genotypes for Harry and Ginny’s hair color? Harry is: Bb Ginny is: bb

7. Given the genotypes of Bb and bb, we can fill in the Punnet Square • Bb Bb • bb bb Their children have a 50% chance of having red hair or brown hair

8. How can Harry help us learn about Dihybrid Squares? Dihybrid squares are punnet squares that look to compare 2 traits and see how they could be inherited

9. Keep in mind that the traits do not have to be inherited together Remember the Law of Independent Assortment Just because Harry has brown hair does not mean he will have magic Just because Ginny has red hair doesn’t mean that she will magic

10. So let’s look at the possible genes for their children! They have 3: Lily Luna, James Sirius and Albus Severus

11. Let’s review the genes for Muggles , Magic, Brown hair and Red hair M= muggleness m= magic ability B = brown hair b= red hair

12. We have already determined the phenotypes for Harry and Ginny Harry is mm for magic and Bb for brown hair… or mmBb Ginny is mm for magic and bb for red hair….or mmbb

13. To figure out what their kids could look like, we must do a dihybrid cross • Harry is mmBb • Factor out the possibilities • mmBb mB Harry can give off the following traits: 1. Take the little m and put it with the B (this is one possibility)

14. To figure out what their kids could look like, we must do a dihybrid cross • Harry is mmBb • Factor out the possibilities • mmBb mBmb Harry can give off the following traits: Take the little m and put it with the B (this is one possibility) Take the little m and put it with the little b

15. To figure out what their kids could look like, we must do a dihybrid cross • Harry is mmBb • Factor out the possibilities • mmBb mBmbmB Harry can give off the following traits: Take the little m and put it with the B (this is one possibility) Take the little m and put it with the little b Go to the second little m and put it with B

16. To figure out what their kids could look like, we must do a dihybrid cross • Harry is mmBb • Factor out the possibilities • mmBb mBmbmBmb Harry can give off the following traits: Take the little m and put it with the B (this is one possibility) Take the little m and put it with the little b Go to the second little m and put it with B Finally take the m and put it with the b We do this because we must “factor” all the possibilities

17. To figure out what their kids could look like, we must do a dihybrid cross • Ginny is mmbb • Factor out the possibilities • mmbb mb Ginny can give off the following traits: 1. Take the little m and put it with the b (this is one possibility)

18. To figure out what their kids could look like, we must do a dihybrid cross • Ginny is mmbb • Factor out the possibilities • mmbb mbmbmbmb Ginny can give off the following traits: Take the little m and put it with the b (this is one possibility) Take the little m and put it with the little b Go to the second little m and put it with b Finally take the m and put it with the b. Ginny can only give recessive genes

19. Now let’s add a Punnet square! This one must be 16 squares to account for every possibility

20. If Harry had mB, mb, mB, mb to give we must place it at the top to account for his genes • mBmbmBmb

21. If Ginny had mb, mb, mb, mb to give we must place it on the sides to account for her genes • mBmbmBmb mb mb mb mb

22. Now let’s factor all these together! • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

23. Now we need to determine the % of phenotypes Go back to the squares and count all the possible phenotypes: We know that the following possibilities could occur: No magic, brown hair No magic, red hair Magic, brown hair Magic, red hair

24. To have no magic, there must be at least ONE big M!Are there any here? • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

25. NOPE!!!!!! • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

26. So our only possibilities are magic and brown hair and magic and red hair • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

27. To have Brown hair, there must be at least one B! How many are here? • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

28. There are 8 Magic and Brown hair • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

29. To have red hair, there must be 2 little b’s! How many are here? • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

30. There are 8 magic and red hair • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

31. So phenotypically Harry and Ginny would have possibilites of : 8 magic and brown haired kids And 8 magic and red haired kids Or we could say a 50% chance of each

32. Now we need to determine the % of genotypes Go back to the squares and count all the possible genotypes:

33. Start with the first box: the genotype is mmBb. How many do you see in the whole square? • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

34. 8 of them are mmBb!! • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

35. How many of them are mmbb? • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

36. There are 8 mmbb • mBmbmBmb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb mbmmBbmmbbmmBbmmbb m

37. So genotypically Harry and Ginny would have possibilities of : 8 mmBb And 8 mmbb Or we could say a 50% chance of each

38. Now let’s Practice!!!! With Harry Potter of course!!!!

39. Question 1: Hermione and Ron marry and have 2 kids (Rose and Hugo). What are the chances that their kids have magic and red hair?

40. As determined before, what are Ron’s and Hermione’s phenotypes? Ron is magic and red hair Hermione is magic and red hair

41. Ron and Hermione are pure recessive, so they have the same genotype: mmbb • mbmbmbmb mb mb mb mb

42. Now let’s factor all these together! • mbmbmbmb mbmmbbmmbbmmbbmmbb mbmmbbmmbbmmbbmmbb mbmmbbmmbbmmbbmmbb mbmmbbmmbbmmbbmmbb m

43. So Ron and Hermione kids, based on the Punnet square 100% will have magic and be red haired!

44. Question 2: Hermione gets put under a spell and marries Dudley. What are the chances their kids will have magic and red hair?

45. We already know the following about Hermione: She has red hair so she must be bb She can do magic so she must be mm

46. Now Dudley is a different story: We know that he has Brown hair so he could be BB or Bb We know that he can not do magic so he is either MM or Mm

47. So let’s use MMBB first for Dudley and Hermione is mmbb • MB MBMBMB mbMmBbMmBbMmBbMmBb mbMmBbMmBbMmBbMmBb mbMmBbMmBbMmBbMmBb mbMmBbMmBbMmBbMmBb m

48. So 100% of their kids would be Muggles with Brown hair Or MmBb

49. Now let’s use MmBb for Dudley and Hermione is mmbb • MB MbmBmb mbMmBbMmbbmmBbmmbb mbMmBbMmbbmmBbmmbb mbMmBbMmbbmmBbmmbb mbMmBbMmbbmmBbmmbb m

50. In this case, the kids would be 25% Muggle with brown hair (MmBb) 25% Muggle with red hair 25% Magic with brown hair 25% Magic with red hair (mmbb)