Hemophilia is a sex-linked disorder in which a person's blood clots very slowly or not at all. Why are males more likely to inherit hemophilia than females?

Hemophilia is the result of a defective X chromosome. males have XY chromosomes; females have XX chromosomes. If a man has a defective X chromosome, he has no normal X chromosome to balance it out. Therefore, he is more likely to present hemophilia. However, a hemophiliac man's male children will all be healthy, assuming his partner is not a hemophiliac, because the defective X chromosome was not passed on. All his daughters will be carriers, though, regardless of whether their mother is a hemophiliac.

Males inherit only one X chromosome, which is from the mother.