Vitamin D receptor gene polymorphisms are not associated with alopecia areata

It has been demonstrated that the vitamin D receptor (VDR) is strongly expressed in key structures of hair follicles, and a lack of VDR leads to alopecia. We investigated whether there was any association between VDR gene polymorphisms (BsmI, ApaI, and TaqI) and alopecia areata (AA).

Thirty-two patients with AA and 27 healthy control subjects were genotyped using polymerase chain reaction and restriction fragment length polymorphism analysis.

In the patient group, the B and b allele frequencies were 53.1% and 46.9%, A and a allele frequencies were 70.3% and 29.7%, and T and t allele frequencies were 62.5% and 37.5%, respectively. In the control group, the corresponding values were 51.9% and 48.1%, 63.0% and 37.0%, and 77.8% and 22.2%, respectively. In the patient group, the BB, Bb, and bb genotype frequencies were 25.0%, 56.2%, and 18.8%, AA, Aa, and aa genotype frequencies were 43.8%, 53.1%, and 3.1%, and TT, Tt, and tt genotype frequencies were 37.5%, 50.0%, and 12.5%, respectively. In the control group, the corresponding values were 11.1%, 81.5%, and 7.4%, 29.6%, 66.7%, and 3.7%, and 63.0%, 29.6%, and 7.4%, respectively. None of the allele or genotype frequencies showed statistically significant differences between the patient and control groups.

These findings suggest that there is no relationship between VDR gene polymorphisms and AA.