Sevim ÇELİK KARAKAŞ, Nurcan ATEŞ ARAS, MERAL URHAN KÜÇÜK, Serap YALIN, Esen AKBAY

The G1057D polymorphism of insulin receptor substrate-2 (IRS2) gene with type 2 diabetes in the Turkish population

Amaç: İnsülin reseptör substratı (IRS) proteini, hedef dokulara insülin sinyalinin iletilmesinde kritik bir öneme sahiptir. IRS-2 knockout farelerin insanlardaki tip 2 diabete benzer bir klinik fenotip gösterdiği tespit edilmiştir. IRS2 geninde çok sayıda polimorfizm belirlenmiş olmakla birlikte farklı populasyonlarda tip 2 diabet ile IRS-2 Gly1057Asp polimorfizmi arasındaki ilişki araştırılmış olup elde edilen sonuçlar oldukça çelişkilidir. Bu çalışmada Türk populasyonunda Diabetes mellitus ile IRS-2 G1057D polimorfizmi arasındaki ilişkiyi araştırmak amaçlanmıştır. Materyal ve Metot: Çalışma populasyonu 328 kişiden oluşmakta olup 138 kişi DM hastası ve 190 kişide kontroldür. DNA periferik kandan izole edilmiş olup IRS2 G1057D polimorfizmi PCR-RFLP yöntemi kullanılarak belirlenmiştir. Bulgular: IRS2 G1057D polimorfizmi genotip dağılımlarının gruplar arasında istatistiksel olarak anlamlı bir farklılık göstermediği tespit edilmiştir. Sonuçlar: Elde edilen bulgular IRS2 G1057D polimorfizminin tip 2 diabetin patogenezinde rolü olmadığını göstermektedir.

Türk populasyonununda tip 2 diabet hastalarında insülin substrat-2 geni g1057d polimorfizmi

Background: Insulin receptor substrate (IRS) proteins are critical to signal transduction in insulin target tissues. IRS-2 knockout mice exhibit a phenotype similar to human type 2 diabetes, characterized by insulin resistance with abnormal glucose tolerance at birth culminating in the development of fasting hyperglycemia in later age. While several polymorphisms have been identified in the IRS-2 gene, the association of the Gly1057Asp polymorphism with type 2 diabetes has been studied in different populations, but the results have been inconsistent. The present study was undertaken to determine IRS-2 G1057D polymorphism association with Diabetes mellitus in Turkish subjects. Material and Methods: The study population consisted of 328 subjects 138 patients with DM and 190 controls. DNA was extracted from peripheral blood. Genetic polymorphism of IRS-2 G1057D was detected by using PCR-based restriction fragment-length polymorphism. Results: The genotype distribution of the IRS2 G1057D polymorphism was not statistically significant between groups. Conclusions: These results strongly argue against a major role of the G1057D IRS-2 polymorphism in the pathogenesis of type 2 diabetes in Turkish subjects.

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