Definition of Bosma arhinia microphthalmia syndrome

Bosma arhinia microphthalmia syndrome: an extremely rare congenital condition causing birth defects, with less than 100 reported individuals affected worldwide. It is characterized by underdevelopment of the eyes (microphthalmia), absence of the nose (arrhinia), and absent sexual maturation. The degree of severity of the defects can vary. Affected people typically have normal intelligence and can lead productive lives with surgical correction of the defects. The cause is poorly understood, and the only known genetic mutation involves the gene SMCHD1. In most cases, this change occurs spontaneously in the egg or sperm cell and is not inherited from a parent. Also known as BAM syndrome, Bosma syndrome, Gifford-Bosma syndrome.