# Genetic Probability (Binomial Expansion)

by fanofdean
Tags: binomial, expansion, genetic, probability
 P: 2 1. The problem statement, all variables and given/known data I'm stuck on a problem with two variables in it. The question wants to know what's the probability of getting 2 boys and 2 girls, with one of the boys being albino. They say one parent is albino and the other is a heterozygous carrier, so the change of getting it is 50% in the children. So by binomial expansion, it's 1 4 6 4 1. I know the two girls and two boys is the middle term with 6(p^2)(q^2) but with q and p being getting a boy or girl at .50 each. But how do I encompass the albino probability in this? Multiply each child by .50? 2. Relevant equations (p^4)+4(p^3)(q)+6(p^2)(q^2)+4(q)(p^3)+(q^4) 3. The attempt at a solution I can easily find the probability of getting two girls and two boys, I would simply use the 6(p^2)(q^2) with p and q being .50 respectively. I just don't know how to factor in the albino part.
 P: 410 Something like that. You should multiply with another binomial probability regarding the 4 children with "albino chromosome".