X-Linked Inheritance in Families

X-linked inheritance explains how traits on the X chromosome are passed through families. In most mammalian species, females have two X sex chromosomes, while males have one X and one Y. A mutation on one X chromosome may be masked in females by a normal allele on the other X. In males, that same mutation is more likely to s...

Because human males and females inherit different numbers of X chromosomes, traits encoded by the X chromosome display different patterns of expression between the sexes. Traits encoded by genes on the X chromosome are said to be X-linked traits. Since females have two copies of the X chromosome and males just one, a recessive mutation on an X-l...