NEET BIOLOGY

Detailed explanation-1: -So a carrier’s son has a 50% chance of having hemophilia. A baby girl will inherit an X chromosome with a dominant gene for normal blood clotting from her father. So the daughter will not have hemophilia.

Detailed explanation-2: -A female with the hemophilia gene is called a hemophilia carrier. Females have two X chromosomes, so the presence of the hemophilia gene on one X does not result in hemophilia. The presence of the normal gene that codes for the production of factor compensates for the defective gene that does not.

Detailed explanation-3: -If the mother has one altered factor gene and the father does not have hemophilia, each son has a 50% chance of having hemophilia and each daughter has a 50% chance of having one altered factor gene, causing her to be a carrier or have hemophilia.

Detailed explanation-4: -So, the correct answer is ‘50% sons will have haemophilia’.

Detailed explanation-5: -Hemophilia can affect women, too When a female has one affected X chromosome, she is a “carrier” of hemophilia. Being a female carrier of hemophilia is not the same as having hemophilia, although female carriers may experience symptoms of hemophilia.