描述
CHILD Syndrome, (Congenital Hemidysplasia with Icthyosiform Erythroderma and Limb Defects; Ichthyosiform Eruthroderma, Unilateral, with Epsilateral Malformations, Especially Absence Deformity of Limbs) is caused by a mutation in the gene encoding NADH steroid dehydrogenase-like protein (NSDHL). A defect in sterol-4 alpha-carboxylate 3-dehydrogenase, which normally catalyzes the reaction 3-beta-hydroxy-4-beta-methyl-5-alpha-cholest-7-ene-4-alpha-carboxylate + NAD+ = 4-alpha-methyl-5-alpha-cholest-7-en-3-one + CO2 + NADH, causes accumulation of 8(9)cholestenol and 8-dehydrocholesterol in plasma. Symptoms of CHILD syndrome include hearing defects, hemidysplasia, unilateral hypomelia, ichthyosiform nevi, limb abnormalities, lung hypoplasia, and punctate calcifications.