مختصر البحثDiabetes mellitus type 2 is a multifactorial, heterogenic disease with a complicated origin. T2DM has
been linked to a significant number of genes throughout the last few decades. TCF7L2 gene is the first
T2DM candidate gene found using genome-wide screening and positional cloning, and TCF7L2 gene
has shown the highest relationship with T2DM among all identified genes to date. This study
demonstrates the link between the gene and diabetes patients in Iraq. For this purpose, a case-control
study with 100 T2DM patients and 100 controls has been conducted. Tetra-Primer ARMS-PCR
Technique has been used to genotype TCF7L2 rs7903146. Statistical analyses have been carried out
using SPSS version.20.0., the comparison of control and T2DM the heterozygous genotype (CT) in the
codominant model shows OR=40.2333(95% CI: 6.0293 to 100.9850, P < 0.0001) in which there is an
increased risk of T2DM about 40 folds in comparison with wild type (CC) after adjustment for age, sex
and BMI. In addition, the (TT) in codominant model states the OR=17.7500(95% CI:
(6.0051 to 52.4659), P < 0.0001) that increases the risk of T2DM about 17 folds in comparison with
wild type (CC). The dominant model represents the comparison of control and T2DM shows CT+TT
the OR=31.8021(95% CI: 13.4618 to 75.1291, P < 0.0001); hemce, there is an increased risk of T2DM
about 31 folds in comparison with wild type. Over Dominant model represents CT with OR=13.9487
(95% CI: ( 6.8372 to 28.4569), P < 0.0001) in which there is an increased risk of T2DM about 13.9
folds in comparison with (CC+CT). Finally, the findings reveal that the TCF7L2 gene polymorphism
(rs7903146) is linked to the risk of T2DM. Genotyping frequency of rs7903146 C/T among male and
female demonstrates significant genotypes (T/T) and C/C with gender. These findings strongly suggest
that the TCF7L2 gene polymorphism (rs7903146) plays a role in the development of T2DM in Iraqi
Arab patients