Contributor: Gordon K. Klintworth
MIDAS syndrome (MIcrophthalmia-Dermal Aplasia-Sclerocornea syndrome, microphthalmia with linear skin defects, MLS syndrome, OMIM #309801) is an X-linked recessive inherited syndrome characterized by bilateral ocular abnormalities (microphthalmos, corneal opacities, anterior chamber anomalies that cause glaucoma, orbital cysts [cyst - orbit]) and irregular raised linear erythematous areas of muscle hmartomas that are exclusively found in the skin of the head and neck. At one time dermal aplasia [aplasia - dermis] or hypoplasia [hypoplasia - dermis] was suspected. The corneal abnormalies are sclerocornea and Peters anomaly. Other reported abnormalities in some cases are a short stature, absence of septum pellucidum, ectopic areas of gray and while matter in the brain, agenesis of corpus callosum, hydrocephalus, seizes, mental retardation, nail dystrophy, diaphragmatic hernia [hernia - diaphragmatic], genital abnormalies (rudimentary uterus, ovotestis), congenital heart disease, and a hypertrophic cardiomyopathy. With the exception of XX males the syndrome only occurs in females and is thought to be lethal in hemizygous males. The responsible gene [ARHGAP6] is on the X-chromosome.The differential diagnosis includes focal dermal hypoplasia, incontinentia pigmenti, Opitz syndrome, and Aicardi syndrome. In contast to focal dermal hypoplasia the skin of only the upper half of the body is involved and fatty tissue does not herniate. Syndactyly, perioral lesions, clefting of the hands and feet and coloboma are absent in MIDAS syndrome