Failure of steroid sulfatase to desulfate vitamin D3 sulfate.

Patients with recessive X-linked ichthyosis lack activity of the enzyme steroid sulfatase. One of the more striking clinical findings in these patients is the improvement in stratum corneum shedding in the summer. Since vitamin D is one steroid responsive to sunlight, we examined whether or not vitamin D3 sulfate is a substrate for steroid sulfatase. Enzyme preparations active against other sulfated steroids caused no desulfation of vitamin D3 sulfate.