Question

Given below is a pedigree chart showing the inheritance of a certain sex-linked trait in humans.
The trait traced in the above pedigree chart is

• A. dominant X-linked
• B. recessive X-linked
• C. dominant Y-linked
• D. recessive Y-linked

Answer 1

Answer: (A)

The disease in the given pedigree chart is $X$-linked dominant because, it is inherited by female child from her father and none of the male child is affected ($X$-linked). As disease expressed in female inspite of two $XX$ chromosomes, it will be dominant.