Is Hemifacial microsomia inherited ?
Is hemifacial microsomia inherited? Hemifacial microsomia most often occurs in a single individual in a family and is not inherited. If the condition is caused by a chromosomal abnormality, it may be inherited from one affected parent or it may result from a new abnormality in the chromosome and occur in people with no history of the disorder in their family. In a very small number of cases, hemifacial microsomia is inherited in an autosomal dominant pattern, which means one copy of an altered gene in each cell is sufficient to cause the disorder. In rare cases, the condition is inherited in an autosomal recessive pattern, 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. The gene or genes involved in hemifacial microsomia are unknown. In some affected families, people seem to inherit an increased risk of developing hemifacial microsomia, not the condition itself. In these cases, some combination of genetic changes and environmental factors may be involved.