association between methylenetetrahydrofolate reductase (mthfr( and 5-methyltetrahydrofolate- homocysteine methyltransferase reductase (mtrr) polymorphisms in iraqi patients with covid-19

Background: the methylenetetrahydrofolate reductase (mthfr) gene is an essential gene in the metabolism of folate-homocysteine. recently, the level of homocysteine was found to be a significant marker in the follow-up of covid-19 infection. thus, this study aimed to detect the effect of genetic polymorphisms for single nucleotide polymorphisms (snps) (c.66a>g, c.1298a>c, and c.677ct) on covid-19 infection. methods: blood samples were collected from 270 patients with covid-19 in the medical center of al-shifa (baghdad, iraq) from november 2020 to march 2021. tetra-primer amplification refractory mutation system-polymerase chain reaction (arms-pcr) technique was used for the detection of genotypes of snps. the odds ratio (or) was used to detect the relationship between snps and covid-19 infections. haplotype analysis was performed by shesis software.results: there was a significant difference between mild/moderate cases and severe/critical cases for ages (35-45), (46-55), and (56-65) years (p<0.0001, p=0.01, and p=0.006, respectively). the results showed significant differences in the t allele for snp c.677>c (p<0.0001 and or=4.58). the c allele for snp c.1298a>c indicated significant differences (p<0.001 and or=3.15). besides, the g allele for snp c.677c>t showed significant differences (p<0.001 and or=6.64). consequently, these snps showed a predisposition to the development of covid-19 infection. with regard to the c-a-a, t-a-a and t-c-g haplotypes indicated significant differences between the control and patient groups. the c-a-a was related to a decreased risk and indicated a protective effect against covid-19 infection development (p<0.0001 and or=0.218). the increased risk was associated with t-a-a and t-c-g haplotypes and indicated the risk impact on covid-19 infection development (p<0.0001, p=0.004, and or=15.5, or=6.772, respectively). furthermore, the linkage disequilibrium (ld) for snps was studied, and the complete d’ value was 99%.conclusion: the genetic polymorphisms of snps (c.66a>g, c.1298a>c, and c.677c>t) in the iraqi population were associated with covid-19 infection.