Lack of Association of Insulin Receptor Substrate Gene Polymorphisms with Obstructive Sleep Apnea Syndrome

Sleep apnea syndrome is associated with increased prevalence of diabetes and has recently shown to be associated with insulin resistance. The aim of the present study was to investigate the relationships between insulin resistance, insulin receptor substrate-1 (IRS-1), insulin receptor substrate-2 (IRS-2) gene polymorphisms and obstructive sleep apnea syndrome (OSAS). The study population consisted of 56 consecutive patients with OSAS and 26 subjects without OSAS were enrolled in the study. Genotyping of IRS-1 and IRS-2 were amplified by polymerase chain reaction (PCR). Insulin resistance was estimated using the homeostasis model assessment (HOMA). In OSAS patients, 2 (3.6%) had G972R gene polymorphism and 54 (96.4%) had no nucleotide substitution in IRS-1 gene whereas in the control group, there was no nucleotide substitution in IRS-1 gene (p>0.05). Besides, 47 OSAS patients (84.0%) had no nucleotide substitution, 3 (5.3%) had G1057D heterozygous, 1 (1.8%) had P1033P heterozygous, 3 (5.3%) had P1033P homozygous and 2 (3.6%) had P1033P heterozygous/G1057D heterozygous polymorphisms in IRS-2 gene. In the control subjects, 21 (80.8%) had no nucleotide substitution, 3 (11.5%) had P1033P homozygous and 2 (7.7%) had P1033P heterozygous polymorphisms in IRS-2 gene (p>0.05). There was no significant difference between two groups in terms of fasting glucose and HOMA-IR. It was observed that IRS-1 and IRS-2 gene polymorphisms didn’t increase risk for OSAS. Besides, there was no association between IRS-1 and IRS-2 polymorphisms and HOMA in OSAS.