A cross-sectional study to find association of VDR gene polymorphism with non-syndromic congenital ichthyosis and with vitamin D deficiency.

Though development of vitamin D deficiency and rickets in patients with congenital ichthyosis (CI) have recently been observed, yet exact cause of such association is not properly understood. To evaluate association between Vitamin D Receptor (VDR) polymorphism and CI, and to identify risk factors responsible for development of vitamin D deficiency in ichthyosis. In this cross-sectional study, detailed history of patients and controls was noted and certain biochemical investigations were made. Immunohistochemical staining of skin tissue was done for VDR expression in epidermal and dermal region of ichthyosis patients. VDR polymorphism was assessed in all participants. Ninety-six subjects, were recruited. Mean serum vitamin D was significantly lower among ichthyosis patients. Cdx-2 polymorphism was found to be significantly associated with ichthyosis (p = 0.009). Within the diseased group, Fok-1 (p = 0.035), age (p = 0.020) and alkaline phosphatase (ALP) (p = 0.007) emerged as factors which might be associated with vitamin D deficiency. Cdx2 polymorphism was significantly associated with CI patients. Also, association of Fok-1 polymorphism along with age and raised serum ALP levels emerged as potential factors for determining CI-related vitamin D deficiency.