<em>Hemophilia typically affects more males than females because the disorder is </em><em>X-linked </em><em>and </em><em>recessive</em><em>. </em>
<u>Females have two X chromosomes (XX) while males only have one X and one Y chromosome (XY). The two X chromosomes in females are capable of carrying alleles while the Y chromosome in males is hypothesized not able to carry alleles. </u>
Consequently, the two X chromosomes in females will both need to carry the recessive allele of hemophilia in order for any female to be affected for hemophilia while the males only need their single X chromosome to carry the recessive allele in order to be affected.
In order words, the presence of a single recessive allele is not enough for a female to be affected while it is more than enough for a male to be affected. Hence, more males are affected b hemophilia disorder than females.
