Congenital alopecia is generally regarded as an uncommon cutaneous anomaly. It is probably more common than is generally believed. The literature contains the reports of many interesting and diversified cases reported under this title.
The loss of hair may be complete and absolute, although these cases are rare. More commonly it consists of an alopecia, with scanty, incompletely grown, or lanugo-like hair. The condition is commonly associated with other defects of development, chief among which are dental aplasias and changes in the nails. In a few instances it has been found in association with anomalies in the sweat glands, impaired senses of taste and smell, absence of the mammary glands and epidermolysis bullosa.
ETIOLOGY
The condition has been seen more in males than in females. The proportion of males affected is about twice that of females. A familial tendency is common. Cases are often seen in brothers and in brother