Supplementary Material for: A Novel Polymorphism (rs35612982) in <b><i>CDKAL1</i></b> Is a Risk Factor of Type 2 Diabetes: A Case-Control Study

<b><i>Background:</i></b> The interaction of environmental factors and genetic factors may contribute to the risk of type 2 diabetes (T2D). We aimed to investigate whether age, gender, body mass index (BMI) and lifestyle factors have an effect on the association between the <i>CDKAL1</i> polymorphisms and T2D. <b><i>Methods:</i></b> Eight single nucleotide polymorphisms in <i>CDKAL1</i> were genotyped by Agena MassARRAY in 508 T2D patients and 503 controls. The association between the <i>CDKAL1</i> polymorphisms and T2D was evaluated using logistic regression model by calculating OR and 95% CIs. <b><i>Results:</i></b> We found a significant association between <i>CDKAL1</i> polymorphisms (rs4712523, OR 1.42, <i>p</i> = 9.44 × 10^–5; rs4712524, OR 1.38, <i>p</i> = 3.28 × 10^–4; rs10946398, OR 1.43, <i>p</i> = 6.21 × 10^–5; rs7754840, OR 1.43, <i>p</i> = 6.33 × 10^–5; rs35612982, OR 1.34, <i>p</i> = 0.0010; and rs10440833, OR 1.32, <i>p</i> = 0.0018) and T2D risk among the Han population from Northwest China. We also found that genetic variants of <i>CDKAL1</i> could modify the risk of T2D that might be influenced by age, BMI and the status of smoking and drinking. Besides, rs35612982-CT (<i>p</i> = 0.038) and rs10440833-AT (<i>p</i> = 0.044) genotypes were higher insulin level. <b><i>Conclusion:</i></b><i> CDKAL1</i> rs35612982 (C/T) polymorphism, as a new polymorphism, was associated with the increased risk of T2D in the Han Chinese population. Moreover, the contribution of<i> CDKAL1</i> polymorphisms to T2D risk seems to be associated with age, gender, BMI, smoking and drinking.