The relationship between polymorphism rs12449964 of the phosphatidylethanolamine- N-methyltransferase gene and hypertriglyceridemia and obesity in patients with type 2 diabetes

Abstract

Phosphatidylethanolamine N-methyltransferase (PEMT) is the enzyme of lipid metabolism that catalyzes the conversion of phosphatidylethanolamine to phosphatidylcholine in a series of three methylation reactions. Low activity of the enzyme can increase the availability of phosphatidic acid for triacylglycerol synthesis and thus favor obesity, one of the most important risk factors for type 2 diabetes (T2D). The aim of the study: To study the relationship of the rs12449964 (C>T) in the regulatory region of the PEMT (phosphatidylethanolamine-N-methyltransferase) gene with blood plasma triglycerides, as well as the risk of obesity and T2D in population of Central Russia. Materials and methods: The study included 2060 unrelated individuals of Slavic origin, including 1024 patients with T2D and 1036 healthy volunteers. Genotyping of PEMT gene polymorphism (C>T, rs12449964) was performed by laser desorption / ionization time-of-flight mass spectrometry using the MassArray Analyzer 4 platform (Agena Bioscience). SNPStats online program was used for statistical analysis of the obtained data. Results: Linear regression analysis did not reveal an association of rs12449964 of the PEMT gene with a risk of developing T2D regardless of body mass index (P>0,05). However, the T/T genotype of the studied SNP is associated with an increased risk of obesity in patients with type 2 diabetes (OR 1.66; 95% CI 1.11-2.46; P = 0.011, adjusted for sex and age, recessive model). In addition, carriage of the T/T genotype was associated with a higher level of triacylglycerols in the blood plasma of patients with T2D, both in the presence of obesity and without it (P<0.05). According to GTEx Portal, the rs12449964T allele is associated with decreased PEMT expression in various tissues. Conclusion: The study revealed for the first time the association of rs12449964 of the PEMT gene with hypertriglyceridemia and an increased risk of obesity in patients with T2D, which may be due to the low transcriptional activity of the phosphatidylethanolamine- N-methyltransferase gene in carriers of the alternative allele of the studied SNP.