Hemophilia is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree. In the pedigree that is shown, which represents Irene's allele combination?

XhXh

XHXh

XHXH

XhY

the answer to the question is XHXH.

The correct answer is XHXH.

Hemophilia is an inherited genetic disease, which damages the tendency of the body to produce blood clots, that is, a procedure required to inhibit bleeding. Hemophilia A and B are both X-linked recessive disorders, though the females are hardly influenced.

X-linked recessive inheritance refers to a kind of inheritance in which a mutation in a gene on the X-chromosome makes the phenotype to be articulated in males hemizygous for the mutation of the gene, as they exhibit one X and one Y chromosome.