What condition is characterized by a deficiency of steroid sulfatase?

X-linked ichthyosis is a genetic condition resulting from a deficiency of steroid sulfatase, an enzyme that is crucial for the proper metabolism of steroids. This deficiency leads to the accumulation of unmetabolized steroid sulfates in the body, particularly impacting the skin and causing the characteristic symptom of dry, scaly skin, often resembling ichthyosis.

This condition is inherited in an X-linked recessive pattern, most commonly affecting males, while females can be carriers and may show mild symptoms or none at all. The diagnosis can often be confirmed through genetic testing that identifies mutations in the STS gene, which encodes for the steroid sulfatase enzyme.

The other conditions in the question do not relate to steroid sulfatase deficiency. Turner syndrome is primarily associated with the absence of all or part of a second X chromosome in females, Prader-Willi syndrome involves genetic imprinting issues on chromosome 15 leading to a range of symptoms including obesity and developmental delays, and Marfan syndrome is a connective tissue disorder caused by mutations in the FBN1 gene, affecting various systems in the body. None of these conditions is linked to a deficiency of steroid sulfatase.