Principle Of Inheritance And Variation Question 381
Question: Human skin colour is controlled by several gene pairs. Let us assume here that there are just three gene pairs on different chromosomes and that for each pair there are two alleles, an incompletely dominant one that codes for melanin deposition and an incompletely recessive one that codes for no melanin deposition. If a very dark skinned person marries a very light skinned woman, what will be the chance that their offspring will have very dark skin?
Options:
A) 1/64
B) 1/4
C) 5/8
D) 9/64
Show Answer
Answer:
Correct Answer: A
Solution:
[a] The phenotypic ratio is 1 very dark: 6 dark: 15 fairly dark : 20 intermediate : 15 fairly light: 6 light: 1 very light, hence very dark Is $ \frac{1}{64} $ .
BETA
