I\'m trying to understand genetic probability. How do you do it? Ex: P1: Rr Dd c
ID: 17909 • Letter: I
Question
I'm trying to understand genetic probability. How do you do it?Ex:
P1: Rr Dd cc Oo Hh Ww X P2: Rr dd Cc oo Hh Ww
How many gametes can be formed by P1?
How many genotypes are possible among the progeny of this cross?
How many phenotypes are possible from this cross?
What is the probability of obtaining the Rr Dd ccOo hh ww genotype in the progeny?
I think the second and third questions are figured out by the forked line method, but I'm not sure.. it might all be probability. help?
Explanation / Answer
a) how many kinds of gametes can be formed by P1? =>P1's gametes= 2^5 = 32 (5 is number of heterozygous genes) b.) How many genotypes are possible among the progeny of this cross? => Split into individual genes. Rr x Rr = 3 genotypes (RR, Rr, rr) Dd x dd = 2 genotypes (Dd, dd) cc x Cc = 2 genotypes Oo x Oo = 3 genotypes Hh x Hh = 3 genotypes Ww x ww = 2 genotypes All together = 3 x 2 x 2 x 3 x 3 x 2 = 216 genotypes c.) how many phenotypes are possible among the progeny? => For complete dominant, each gene produces 2 phenotypes. All together produce = 2 x 2 x 2 x 2 x 2 x 2 = 64 phenotypes what is the probability of obtaining the Rr Dd cc Oo hh ww genotype in the progeny? =>From answer b) you can calculate the probability each gene and the combine together: Rr Dd cc Oo hh ww = 0.5 x 0.5 x 0.5 x 0.5 x 0.25 x 0.5 = 0.0078125