Answer: probability that both twins are affected is 0.0625 while the probability that both twins are unaffected is 0.5625
Explanation:
If both parents are heterozygous for albinism, it means they both have one recessive allele (Aa) each.
The possible genotype outcome of one child will be
AA Aa Aa aa
Therefore the possiblility one child will inherit both recessive allele (aa) is 1/4 and the probability that one child is unaffected is 3/4
If the had a dizygoyic twins this means the two children have different DNA.
So also the possibility of the second child to inherit both recessive allele (aa) is 1/4
The probability that both the twins are affected is
1/4 * 1/4 =1/16 = 0.0625
The probability that both are unaffected is
3/4 * 3/4 = 9/16 = 0.5625
Answer: The probability of both twins being unaffected is 9/16 = 0.5625.
The probability of both twins being affected is 1/16 = 0.0625
Explanation: Since the two parents are heterozygous for a recessive allele for albinism, therefore their genotype is Aa.
A cross between them will produce the following possible genotypes: AA, Aa, Aa and aa.
_ A a
A AA Aa
a Aa aa
The probability of one child being unaffected is 3/4. The probability of both twins being unaffected is 3/4 x 3/4 = 9/16
=0.5625
The probability of one child being affected is 1/4
The probability of both twins being affected is 1/4 x 1/4= 1/16
=0.0625.
