Ichthyosis, X-Linked, Without Steroid Sulfatase Deficiency

Clinical Features

A common form of X-linked ichthyosis (308100), also known as steroid sulfatase deficiency, is caused by mutation in the STS gene (300747). Robledo et al. (1995) described a Sardinian kindred in which congenital ichthyosis was associated with normal levels of steroid sulfatase and a normal pattern on Southern blot analysis suggesting the presence of an intact STS gene.

Mapping

Although the pedigree pattern in the kindred with ichthyosis studied by Robledo et al. (1995) was entirely consistent with X-linked recessive inheritance, the disorder was found to segregate independently of genetic polymorphisms detected by probes mapping to Xp22.3, where the STS gene maps. The search for linkage to markers elsewhere on the X chromosome had not been successful. Robledo et al. (1995) concluded that there may be a form of X-linked ichthyosis due to some mechanism other than STS deficiency.