Kahrizi syndrome is a novel autosomal recessive syndrome characterized by severe mental retardation, coloboma, cataract, and kyphosis. It has been reported that mutations in SRD5A3 cause this syndrome. SRD5A3 encodes steroid 5 alpha-reductase type 3, an enzyme which is required for the conversion of polyprenol to dolichol, the lipid anchor for N-glycosylation in the endoplasmic reticulum. SRD5A3 is highly expressed in fetal brain.
