JOURNAL OF ENDOCRINOLOGICAL INVESTIGATION, cilt.33, sa.7, ss.451-454, 2010 (SCI-Expanded)
Background: Recent studies have indicated that polymorphisms of the interleukin-18 (IL-18) and interleukin-12 (IL-12) genes are associated with the development of Type 1 diabetes mellitus (T1 DM) in some populations, but not all. Aim: The present study was designed to examine the roles of polymorphisms in the IL-18 promoter and IL-12p40 with respect to susceptibility to T1 DM in Turkish patients. Subjects and Methods: Ninety-one patients with T1 DM and 87 unrelated healthy subjects were included in the study. The IL-18 polymorphisms at positions -607 and -137 were detected by a sequence-specific PCR method. The single nucleotide polymorphism in the IL-12p40 3' untranslated region (3'-UTR) at position +1188 was analyzed by the PCR-restriction fragment length polymorphism (RFPL) method. Results: The allelic and genotypic frequencies of the IL-18 and IL-12p40 polymorphisms did not differ significantly between subjects with T1 DM and the controls (p>0.05). However, diabetic patients with the -137 (CC) genotype showed a younger onset age compared to patients with the -137 (GG) genotype (p=0.02). In addition, patients with the -607 (CC) genotype had higher levels of glycated hemoglobin (HbA(1c)) than patients with the -607 (AC) genotype (p=0.004). Furthermore, patients with the IL-12p40 (AC) genotype had higher HbA(1c) levels than patients with the IL-12p40 (AA) genotype (p=0.01). Conclusions: The results of the present study show that the IL-18 and IL-12p40 polymorphisms may have some effect on the onset age and deterioration of glycemic control in Turkish patients with T1 DM. (J. Endocrinol. Invest. 33: 451-454, 2010) (c) 2010, Editrice Kurtis