X-linked ichthyosis is a relatively common genetic disorder of keratinization. It is the second most common type of ichthyosis after vulgaris. The incidence is estimated to be between 1 in 2,000 and 1 in 6,000 male live births.
Synonyms and Related Disorders
Placental steroid sulfatase deficiency; Steroid sulfatase deficiency
Usually affects males only
Transmitted by carrier females (about 1 in 2,000 women are carriers of steroid sulfatase (STS) enzyme deficiency)
Most apparently, sporadic cases appear to be inherited based on biochemical analysis (as their mothers showed low values of STS enzyme activity).
Reports of a few affected female patients
Etiology (Janniger and Schwartz 2001)
Caused by a deficiency of STS enzyme
The STS gene
Mapped on the distal part of the short arm of the X chromosome (Xp22.3)
Close to the pseudoautosomal region
Unlike most X-chromosome genes, the STS...
KeywordsDown Syndrome Testicular Cancer Kallmann Syndrome Steroid Sulfatase Sulfated Steroid
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