X-linked Dominant: Incontinentia Pigmenti
Genes are inherited from our biological parents in specific ways. One of the basic
patterns of inheritance of our genes is called X-linked dominant inheritance.
What is X-linked dominant inheritance?
X-linked dominant inheritance occurs when a gene responsible for a trait or disorder
is located on the X chromosome. The gene acts in a dominant manner. This means that
both males and females can display the trait or disorder when they have only one copy
of the gene inherited from a parent.
Depending on the disorder, a gene that is X-linked dominant may cause a pregnancy
with a male not to survive. Scientists and doctors say that there is "lethality" in
males. This means that the gene can be passed from mother to daughter, but if passed
to a son, then the pregnancy miscarries. Only those sons without the gene survive
and are born healthy. One example of an X-linked dominant condition is called incontinentia
What is incontinentia pigmenti?
IP is extremely rare. The main features occur in the skin where a blistering rash
occurs in newborns. This is followed by the blisters becoming raised, like warts.
Next, brown swirls appear in the skin, followed by the appearance of light-colored
swirls. The result is a "marble-cake–like" appearance on the skin. Other health problems
can be seen in IP involving the eyes, central nervous system, teeth, nails, and hair.
The severity varies from person to person.