Karambataki Maria, Malousi Andigoni, Tzimagiorgis Georgios, Haitoglou Constantinos, Fragou Aikaterini, Georgiou Elisavet, Papadopoulou Foteini, Krassas Gerasimos E, Kouidou Sofia
Laboratory of Biological Chemistry, Department of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; Department of Endocrinology, Diabetes and Metabolism, Panagia General Hospital, Thessaloniki 55132, Greece.
Laboratory of Biological Chemistry, Department of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
Biomed Rep. 2017 Feb;6(2):146-158. doi: 10.3892/br.2016.833. Epub 2016 Dec 29.
Coding synonymous single nucleotide polymorphisms (SNPs) have attracted little attention until recently. However, such SNPs located in epigenetic, CpG sites modifying exonic splicing enhancers (ESEs) can be informative with regards to the recently verified association of intragenic methylation and splicing. The present study describes the association of type 2 diabetes (T2D) with the exonic, synonymous, epigenetic SNPs, rs3749166 in calpain 10 (CAPN10) glucose transporter (GLUT4) translocator and rs5404 in solute carrier family 2, member 2 (SLC2A2), also termed GLUT2, which, according to prior bioinformatic analysis, strongly modify the splicing potential of glucose transport-associated genes. Previous association studies reveal that only rs5404 exhibits a strong negative T2D association, while data on the CAPN10 polymorphism are contradictory. In the present study DNA from blood samples of 99 Greek non-diabetic control subjects and 71 T2D patients was analyzed. In addition, relevant publicly available cases (40) resulting from examination of 110 Personal Genome Project data files were analyzed. The frequency of the rs3749166 A allele, was similar in the patients and non-diabetic control subjects. However, AG heterozygotes were more frequent among patients (73.24% for Greek patients and 54.55% for corresponding non-diabetic control subjects; P=0.0262; total cases, 52.99 and 75.00%, respectively; P=0.0039). The rs5404 T allele was only observed in CT heterozygotes (Greek non-diabetic control subjects, 39.39% and Greek patients, 22.54%; P=0.0205; total cases, 34.69 and 21.28%, respectively; P=0.0258). Notably, only one genotype, heterozygous AG/CC, was T2D-associated (Greek non-diabetic control subjects, 29.29% and Greek patients, 56.33%; P=0.004; total cases, 32.84 and 56.58%, respectively; P=0.0008). Furthermore, AG/CC was strongly associated with very high (≥8.5%) glycosylated plasma hemoglobin levels among patients (P=0.0002 for all cases). These results reveal the complex heterozygotic SNP association with T2D, and indicate possible synergies of these epigenetic, splicing-regulatory, synonymous SNPs, which modify the splicing potential of two alternative glucose transport-associated genes.
编码同义单核苷酸多态性（SNPs）直到最近才受到较少关注。然而，位于表观遗传的CpG位点且修饰外显子剪接增强子（ESEs）的此类SNPs，对于最近证实的基因内甲基化与剪接的关联可能具有参考价值。本研究描述了2型糖尿病（T2D）与钙蛋白酶10（CAPN10）葡萄糖转运蛋白（GLUT4）转运体中的外显子、同义、表观遗传SNPs rs3749166以及溶质载体家族2成员2（SLC2A2，也称为GLUT2）中的rs5404之间的关联，根据先前的生物信息学分析，这两个SNPs强烈改变了葡萄糖转运相关基因的剪接潜能。先前的关联研究表明，只有rs5404与T2D呈强负相关，而关于CAPN10多态性的数据则相互矛盾。在本研究中，分析了99名希腊非糖尿病对照受试者和71名T2D患者血液样本中的DNA。此外，还分析了从110个个人基因组计划数据文件检查中获得的相关公开可用病例（40例）。rs3749166 A等位基因在患者和非糖尿病对照受试者中的频率相似。然而，AG杂合子在患者中更为常见（希腊患者中为73.24%，相应的非糖尿病对照受试者中为54.55%；P = 0.0262；所有病例中分别为52.99%和75.00%；P = 0.0039）。rs5404 T等位基因仅在CT杂合子中观察到（希腊非糖尿病对照受试者中为39.39%，希腊患者中为22.54%；P = 0.0205；所有病例中分别为34.69%和21.28%；P = 0.0258）。值得注意的是，只有一种基因型，即杂合子AG/CC与T2D相关（希腊非糖尿病对照受试者中为29.29%，希腊患者中为56.33%；P = 0.004；所有病例中分别为32.84%和56.58%；P = 0.0008）。此外，AG/CC与患者中非常高（≥8.5%）的糖化血浆血红蛋白水平密切相关（所有病例中P = 0.0002）。这些结果揭示了复杂的杂合SNP与T2D的关联，并表明这些表观遗传、剪接调节、同义SNPs可能存在协同作用，它们改变了两个替代葡萄糖转运相关基因的剪接潜能。
