Human beta defensin-1(hBD-1); an antimicrobial peptide, has immune regulatory
effects which may be involved in autoimmunity. The aims were to evaluate the association
between defensin beta 1 (DEFB1) (-44 C/G) and (-20 G/A) gene polymorphisms
with the risk of vitiligo development, the extent of the disease and the
response to NB-UVB treatment in a sample of Egyptian population. 178 active nonsegmental
vitiligo patients and 182 control subjects were included in this prospective
case control study. Vitiligo extent was evaluated using vitiligo area scoring index
(VASI). Gene polymorphisms in all participants were studied by RFLP PCR technique.
Patients were treated by three narrowband UVB (NB-UVB) treatment sessions per
week. After 12 weeks, the patients were reevaluated clinically to assess the extent of
the disease using VASI scoring again and to evaluate the type of repigmentation, if
any. AA genotype of DEFB1 (-20G/A) has a protective role against vitiligo development,
while (DEFB1 -44 C/G) GG genotype and G allele increase the risk of vitiligo
development about two folds. Patients carrying polymorphism in DEFB1 (-20G/A)
only showed the lowest VASI scores (14.23 ± 2.77) and the highest percentage of
improvement (66.12 ± 18.01%), while patients carrying polymorphism in DEFB1(-44
C/G) only showed the highest baseline VASI scores (38.87 ± 6.7) and the lowest therapeutic
response (23.79 ± 19.42%) among all patients groups. Different DEFB1 gene
polymorphisms may modify the risk of vitiligo development, the disease extent and
the response to NB-UVB phototherapy.