Question

In humans, albinism (lack of pigment isn’t he skin and eyes and hair) is due to recessive gene. Suppose that a normally pigmented man and an albino woman produce an albino child. What are the chances of their second child also being albino? ( does anyone knows the answer to this question)

Answer 1

Answer:

There are equal chances for the second child becoming albino and not becoming albino.

Explanation:

Albinism is due to the presence of a recessive gene. Thus every individual should have two copies of this recessive gene in order to be an albino. Recessive genes express only if they occur in pair.  

If not the dominant gene trait will be expressed in the organism. Here an albino woman is having children with a normally pigmented man. The cross can be represented as

Let p represent the abnormal pigment gene in albino and P represent the gene for normal pigmentation. The fact that the first child is albino suggests that the genotype of the man is Pp.  

$Pp \times pp$

Pp                               Pp                               pp                        pp

Here there is equal probability for the child becoming and not becoming albino.Thus the probability that the second child also being albino is ½.