Polymorphisms in the Melanocortin-1 Receptor (Mc1R) Gene in Vitiligo

Abstract

Objective: Vitiligo is a progressive skin pigmentation disorder, which may be acquired or hereditary, frequently seen, and may influence every age group. The melanocortin 1 receptor (MC1R) gene is a major determinant of human pigmentation. In our study, polymorphic differences of the MC1R gene at the DNA level has been investigated in patients with vitiligo. Materials and Methods: In our study, polymorphic differences of the MC1R gene at the DNA level has been investigated in vitiligo 60 patients, whose families had resided in the Thrace region of Turkey for at least three generations. The 60 volunteer healthy individuals have no other systemic and dermatological disease. Results: Totally, five types of Single Nucleotide Polymorphism (SNP) were found in each case and control groups: Val60Leu (G178T), Val92Met (G274A), Arg151Cys (C451T), Arg160Trp (C478T), and Arg163Gln (G488A). Comparing both groups in terms of genotype frequencies, no statistically meaningful difference was detected (p>0.05). However, assessing in terms of allele frequencies, a meaningful difference was found in the Arg163Gln (G488A) allele statistically in favor of the control group (p<0.05). Conclusion: It has been found in our study population that the MC1R gene Arg163Gln (G488A) allele may be a protective factor for vitiligo. Turkish Başlık: Vitiligoda Melanokortin-1 Reseptör Geni Polimorfizmleri Anahtar Kelimeler: Vitiligo, Melanokortin-1 Reseptör Geni, Polimorfizm Amaç: Vitiligo; her yaş grubunda, herediter veya kazanılmış olarak ve sıklıkla görülen, ilerleyici, bir deri pigmentasyon bozukluğudur. Melanokortin 1 reseptör (MC1R) geni insan pigmentasyonunda major bir belirleyicidir. Bizim çalışmamızda; vitiligolu olgularda MC1R genindeki polimorfik farklılıklar DNA seviyesinde araştırılmaktadır. Hastalar ve Yöntemler: Bizim çalışmamızda; MC1R genindeki polimorfik farklılıklar en az üç kuşaktır Türkiye'nin Trakya bölgesinde yaşayan, başka bir diğer sistemik veya dermatolojik bir hastalığı olmayan, 60 vitiligolu olguda ve 60 gönüllü sağlıklı bireyde DNA seviyesinde araştırılmıştır. Bulgular: Kontrol ve olgu gruplarının her birisinde toplam 5 adet SNP bulunmuştur. Val60Leu (G178T), Val92Met (G274A), Arg151Cys (C451T), Arg160Trp (C478T) and Arg163Gln (G488A). Genotip sıklıkları yoluyla her iki grup karşılaştırıldığında istatistiki olarak anlamlı bir fark bulunmadı (p>0.05). Ancak allel sıklıkları yoluyla değerlendirildiğinde kontrol grubunun lehine Arg163Gln (G488A) allelinde istatistiki olarak anlamlı bir fark bulundu(p<0.05). Sonuç: Bundan dolayı, bizim çalışmamıza göre MC1R geni Arg163Gln (G488A) alleli vitiligo için koruyucu bir faktör olabilir.

Keywords

• Vitiligo, MC1R, melanocortin-1 receptor gene, polymorphism

Polymorphisms in the Melanocortin-1 Receptor (Mc1R) Gene in Vitiligo

Öz

Kaynakça

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