Maternal methylenetetrahydrofolate reductase C677T polymorphism and down syndrome risk: a meta-analysis from 34 studies

• Published in: PloS one 2014, Vol.9 (9), p.e108552-e108552
• Main Authors: Rai, Vandana, Yadav, Upendra, Kumar, Pradeep, Yadav, Sushil Kumar, Mishra, Om Prakesh
• Format: Article
• Language: English
• Subjects: Bias; Biology and Life Sciences; Biotechnology; Chromosomes; Confidence intervals; Defects; Deoxyribonucleic acid; DNA; DNA methylation; Down syndrome; Down Syndrome - epidemiology; Down Syndrome - genetics; Down's syndrome; Female; Folic acid; Gene polymorphism; Genes; Genetic Association Studies; Genetic Predisposition to Disease; Genetics; Homocysteine; Humans; Laboratories; Medical ethics; Medicine and Health Sciences; Meta-analysis; Metabolism; Methionine; Methylenetetrahydrofolate reductase; Methylenetetrahydrofolate Reductase (NADPH2) - genetics; Polymorphism; Polymorphism, Single Nucleotide; Pregnancy; Risk; Risk analysis; Risk assessment; Risk Factors; Scientific papers; Search engines; Studies; Vitamin B; Vitamin deficiency
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0108552

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme of folate metabolic pathway which catalyzes the irreversible conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. 5-methyltetrahydrofolate donates methyl group for the methylation of homocysteine to methionine. Several studies have investigated maternal MTHFR C677T polymorphism as a risk factor for DS, but the results were controversial and inconclusive. To come into a conclusive estimate, authors performed a meta-analysis. A meta-analysis of published case control studies was performed to investigate the association between maternal MTHFR C677T polymorphism and Down syndrome. PubMed, Google Scholar, Elsevier, Springer Link databases were searched to select the eligible case control studies using appropriate keywords. The pooled odds ratio (OR) with 95%confidence interval were calculated for risk assessment. Thirty four studies with 3,098 DS case mothers and 4,852 control mothers were included in the present meta-analysis. The pooled OR was estimated under five genetic models and significant association was found between maternal MTHFR 677C>T polymorphism and Down syndrome under four genetic models except recessive model (for T vs. C, OR = 1.26, 95% CI = 1.09-1.46, p = 0.001; for TT vs. CC, OR = 1.49, 95% CI = 1.13-1.97, p = 0.008; for CT vs. CC, OR = 1.29, 95% CI = 1.10-1.51, p = 0.001; for TT+CT vs. CC, OR = 1.35, 95% CI = 1.13-1.60, p = 0.0008; for TT vs. CT+CC, OR = 0.76, 95% CI = 0.60-0.94, p = 0.01). The results of the present meta-analysis support that maternal MTHFR C677T polymorphism is a risk factor for DS- affected pregnancy.