X-Linked Traits

X-linked traits are carried on the X chromosome. Since males have one X chromosome and one Y chromosome, they are more susceptible to X-linked diseases, such as hemophilia. There are other traits found on the X chromosome that are not diseases, such as pattern baldness. Since males only have one X chromosome they only need one copy of the gene to start early balding, females need two. Since this ratio is so skewed, there are much fewer females with X-linked diseases than males.

Source: http://en.wikipedia.org/wiki/X-linked_recessive_inheritance

The picture above shows the inheritance of X-linked recessive traits in families. A father cannot pass on an X-linked disease to a son, only a daughter. A daughter will only show the trait if she receives both affected alleles from both parents. A only has to receive the affected allele from the mother to get the disease.

Some X-linked traits are hemophilia, color blindness, and pattern baldness. Do you know of any others?