MTHFR C677T polymorphism frequency and DNA methylation status in Georgian population with non-autoimmune hypothyroidism

Association of methylenetetrahydrofolate reductase ( MTHFR ) gene polymorphisms (C677T and A1298C) with thyroid dysfunction: A meta-analysis and trial sequential analysis

“…A case-control study was excluded because the data were unusable ( 36 ). Finally, a total of seven papers ( 5 , 6 , 28 , 30 - 32 , 37 ) were eligible for quality evaluation ( Table S1 ), but one publication ( 28 ) was excluded for its low NOS scores. Therefore, six publications ( 5 , 6 , 30 - 32 , 37 ) were eligible for data extraction, two ( 6 , 31 ) of which contained two separate studies.…”

“…Finally, a total of seven papers ( 5 , 6 , 28 , 30 - 32 , 37 ) were eligible for quality evaluation ( Table S1 ), but one publication ( 28 ) was excluded for its low NOS scores. Therefore, six publications ( 5 , 6 , 30 - 32 , 37 ) were eligible for data extraction, two ( 6 , 31 ) of which contained two separate studies. Therefore, eight studies from six publications were ultimately included in this meta-analysis ( Figure 1 ).…”

“…To date, several studies ( 5 , 6 , 27 - 32 ) have been carried out to explore the potential association between MTHFR gene polymorphisms and thyroid diseases (HT, GD, and subclinical/overt hyper- and hypothyroidism), but the results remain controversial. Here, we conducted a meta-analysis of all case-control and cohort studies to shed some light on the association between the MTHFR C677T and A1298C polymorphisms and thyroid dysfunction.…”