DEFB1 gene polymorphisms modify vitiligo extent and response to NB-UVB phototherapy

Area of Science:

• Genetics and Immunology
• Dermatology

Background:

• Human beta defensin-1 (hBD-1) is an antimicrobial peptide with potential immune-regulatory roles in autoimmunity.
• Vitiligo is an autoimmune condition where genetic factors may influence disease susceptibility and progression.

Purpose of the Study:

• To investigate the association between DEFB1 gene polymorphisms (at positions -44 C/G and -20 G/A) and vitiligo development.
• To evaluate the impact of these polymorphisms on vitiligo extent and response to narrowband UVB (NB-UVB) treatment.

Main Methods:

• A case-control study involving 178 vitiligo patients and 182 controls from Egypt.
• Genotyping of DEFB1 polymorphisms using RFLP PCR.
• Assessment of vitiligo extent via Vitiligo Area Scoring Index (VASI) before and after 12 weeks of NB-UVB therapy.

Main Results:

• The DEFB1 (-20 G/A) AA genotype showed a protective effect against vitiligo.
• The DEFB1 (-44 C/G) GG genotype and G allele were associated with a two-fold increased risk of vitiligo.
• Patients with DEFB1 (-20G/A) polymorphism had lower VASI scores and better NB-UVB treatment response, while those with DEFB1 (-44 C/G) had higher VASI scores and poorer response.

Conclusions:

• DEFB1 gene polymorphisms play a significant role in vitiligo susceptibility.
• These genetic variations may influence the clinical presentation and therapeutic outcomes of vitiligo, particularly in response to NB-UVB phototherapy.