Are Birthmarks Genetic? The Inheritance of Different Types of Birthmarks
Birthmarks are blemishes or growths formed on the skin before a baby is born. These marks may then be retained as the child grows up or may be lost with time. It is also possible that birthmarks may pop up within a few weeks after birth, though the majority are formed before delivery. Very little is known about the cause of birthmarks and there are no known ways of preventing them either.
Birthmarks can occur anywhere on the body and for the most part are completely harmless. It is generally believed that most are not inherited, although some are. There is plenty of anecdotal information about several generations of family members having similar size, shape and location of birthmarks.
Vascular or Red Birthmarks
Birthmarks can occur anywhere on the skin, and are broadly grouped into pigmented birthmarks and vascular or red birthmarks.
Vascular/Red Birthmark are formed by the overgrowth of blood vessels anywhere on the skin, and they occur with a greater frequency in females than males. In addition Caucasian babies with a body weight of less than 2.2 pounds have a 26% chance of having vascular birthmarks. Vascular birthmarks are further grouped into macular & hemangioma.
Macular birthmarks are caused by capillaries that are visible through the skin. Generally pink in color or shades thereof they mostly occur on the forehead, eyelids and neck regions. These generally fade away as the baby grows up. Hemangiomas are generally caused by a larger number of blood vessels getting closely packed at the surface of the skin. They usually fade with time as well.
Pigmented birthmarks, as the name suggests are usually colored regions in the skin that differ in shade. The most common form of pigmented birthmark is the port-wine stain, which is caused by dilated blood capillaries. The port-wine stain variety of birthmarks are usually red, blue or purple colored and they are usually permanent. If they are too big and disfiguring, port-wine stain birthmarks can be removed by surgery. Large port-wine birthmarks are sometimes caused by an inherited genetic disorder called neurofibromatosis which produces non-cancerous tumours in nerve cells along the skin.
Characteristic symptoms of neurofibromatosis are multiple port-wine birthmarks and they can be located anywhere on the body, including the tongue.