CTLA-4 A49G gene polymorphism is not associated with vitiligo in South Indian population

Abstract

Background: Vitiligo or leukoderma is a chronic skin condition that causes loss of pigment due to destruction of melanocytes, resulting in irregular pale patches of skin. Vitiligo is a polygenic disease and is associated with autoimmunity with an unknown etiology. Aims: One of the candidate genes which has a strong association with several autoimmune diseases is ctla0 -4 gene located in chromosome 2q33 region. We investigated the possible association between ctla0 -4 gene polymorphism in exon 1 (A49G) and vitiligo in patients from South India and compared the distribution of this polymorphism to matched control groups. Patients and Methods: The polymorphism was detected by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method in 175 patients and 180 normal, age/ethnicity matched individuals. Consistency of genotype frequencies with the Hardy-Weinberg equilibrium was tested using a ÷2 test. Results: There was no significant difference between the genotype (P=0.93) and allele (P=0 .615) frequencies of CTLA-4 A49G polymorphism in patients and normal healthy individuals. However there was significant association of the CTLA-4 genotype ( P=0.02) and allelic frequency ( P=0.008) between the segmental and non-segmental sub groups within vitiligo. Conclusion: Our results indicate that there is no association between CTLA-4 A49G gene polymorphism and vitiligo in southern Indian population.

Keywords

• Autoimmune
• CTLA-4
• melanocytes
• polymorphism
• vitiligo