Association analysis between ARG1 gene polymorphisms and idiopathic dilated cardiomyopathy

The current study aimed at investigate the potential association of ARG1 polymorphisms in subjects affected by idiopathic dilated cardiomyopathy (IDCM). We have investigated 352 subjects affected by IDCM and 352 population-matched healthy controls by exploiting case-control study. The serum lipids were quantified using spectrophotometric assay, serum arginase activity was done by enzyme colorimetric assay and 2 polymorphisms (rs2781666 and rs2781667) in ARG1 were typed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) to find out disease associate allele/haplotype segregating in subjects affected by IDCM. Significantly high arginase activity was found to be associated with IDCM subjects when compared with population-matched healthy controls (P < .0001). The higher arginase level in IDCM subjects is negatively correlated with nitrite and nitrate (r = -0.4687, and r = -0.6435, respectively) in our study. There was a significant difference in the distribution of rs2781666 and rs2781667 genotypes of ARG1 polymorphism in patients and controls (P < .0001). Similarly, variant allele T at both loci showed a significant association with the disease phenotypes (P < .0001). Haplotype TT at rs2781666G/T and rs2781667C/T also showed a significantly association (P < .0001). To our knowledge, this is the first report to show a significant involvement of ARG1 polymorphisms to produce IDCM symptoms in subjects originating in Pakistan.