Question: How many people are affected by nonsyndromic aplasia cutis congenita ?
Answer: Aplasia cutis congenita affects approximately 1 in 10,000 newborns. The incidence of the nonsyndromic form is unknown.
Source: GHR

Question: What are the genetic changes related to nonsyndromic aplasia cutis congenita ?
Answer: Nonsyndromic aplasia cutis congenita can have different causes, and often the cause is unknown. Because the condition is sometimes found in multiple members of a family, it is thought to have a genetic component; however, the genetic factors are not fully understood. Researchers suggest that genes important for skin growth may be involved. It is thought that impairments of skin growth more commonly affect the skin at the top of the head because that region needs to be able to grow quickly to cover the fast-growing skull of a developing baby. In some cases, nonsyndromic aplasia cutis congenita is caused by exposure to a drug called methimazole before birth. This medication is given to treat an overactive thyroid gland. Babies whose mothers take this medication during pregnancy are at increased risk of having the condition. In addition, certain viral infections in a pregnant mother can cause the baby to be born with the skin lesions characteristic of nonsyndromic aplasia cutis congenita. Other cases are thought to be caused by injury to the baby during development.
Source: GHR

Question: Is nonsyndromic aplasia cutis congenita inherited ?
Answer: Most cases of nonsyndromic aplasia cutis congenita are sporadic, which means they occur in people with no history of the disorder in their family. When the condition runs in families, inheritance usually follows an autosomal dominant pattern, which means one copy of an altered gene in each cell is sufficient to cause the disorder. Rarely, the condition appears to follow an autosomal recessive pattern of inheritance, which means both copies of a gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
Source: GHR