Question
Question: Two genes A and B are autosomal while h is sex linked. A man with Aabb genotype with son his X chr...
Two genes A and B are autosomal while h is sex linked.
A man with Aabb genotype with son his X chromosome, will produce how many sperms with
abh genotype?
A. 21
B. 41
C. 81
D. 161
E. None of these.
Solution
One of the sex chromosomes, the X and Y chromosomes, were inherited in sex-related disorders. When an unhealthy gene from one parent causes a disorder, even though a matching gene from the other parent is regular, this is known as dominant inheritance. The term "autosomal" refers to a gene that is only on one of the marked, or non-sex, chromosomes.
Complete answer:
Option A: In the above question two genes are given- A and B that are autosomal but it is sex linked.
The genotype of a man given is Aabb genotype.
We need to find out the sperm with abh genotype.
Genotype will beAabbXhY
Gametes- AbXh, AbY, abXh, aBY.
There are four gametes hence the abh genotype is 21.
So, option A is correct.
Option B: 41 is not the correct value.
So, option B is not correct.
Option C: 81 is not the correct value.
So, option C is not correct.
Option D: 161 is not the correct value.
So, option D is not correct.
Option E: 21 is the correct value.
So, option E is not correct.
So, Option B is the correct answer.
Note:
The term "dominant" refers to the fact that a single copy of the disease-causing gene is sufficient to trigger the disease. An autosomal dominant genetic disorder such as Huntington's disease is a typical example. When a gene mutation (allele) is found on a sex chromosome (allosome), sex related explains the sex-specific patterns of inheritance and appearance. Since humans have three times as many genes on the X chromosome as the Y chromosome, there are many more X-linked conditions than Y-linked conditions. Since they lack a second X chromosome with a stable copy of the gene, only females may be carriers for X-linked conditions; males will still be affected by some X-linked disease. As a result, males are affected much more often than females by X-linked recessive disorders.