Association between MTHFR 677C/T polymorphism and psoriasis risk: a meta-analysis

Abstract

ABSTRACT. Previous studies investigating the association between methylenetetrahydrofolate reductase (MTHFR) 677C/T polymorphisms and psoriasis risk have reported inconsistent results. The present metaanalysis aimed to comprehensively evaluate the association between MTHFR 677C/T polymorphism and psoriasis risk. The studies regarding the association between MTHFR 677C/T polymorphism and psoriasis risk were retrieved from the PubMed, Embase, Web of Science, Chinese National Knowledge Infrastructure, and Chinese Biomedical databases. Data were extracted and statistical analysis was performed with the program STATA 12.0. A total of seven studies involving 1290 psoriasis cases and 1068 healthy controls were retrieved. Combined analysis showed that there was no significant difference in MTHFR 677C/T genotype distribution between psoriasis and control subjects in the comparisons C vs T, CC vs CT + TT, CC + CT vs TT, CC vs TT, Subgroup analysis by ethnicity also showed no significant association between MTHFR 677C/T polymorphism and psoriasis risk in both Asian and Caucasian populations. In conclusion, this meta-analysis indicates that MTHFR 677C/T polymorphism may not be associated with psoriasis risk.

Homocysteine

“…Fourteen rare mutations in the MTHFR gene associated with severe enzymatic deficiency and one common polymorphism C677T associated with a milder enzymatic deficiency have been identified, but only the MTHFR gene (677C>T) polymorphism, which causes an Ala-to-Val substitution, has been demonstrated to be associated with psoriasis. [ 63 64 ] The homozygous form of the MTHFR gene at nucleotide 677 (C677T) is prevalent in 10% of the population. The MTHFR genotype of T/T has been reported to reduce the homocysteine response to folic acid to a greater extent than C/C or C/T.…”

Possible association between germline methylenetetrahydrofolate reductase gene polymorphisms and psoriasis risk in a Turkish population

“…Changes in folate status have also been reported as a risk factor in some cases of psoriasis . MTHFR gene variation and differences in presentation of the disease in varying ethnicities or populations have led to discrepancies between studies, and there is little information available on the association between MTHFR polymorphisms and psoriasis vulgaris . Different studies have reported conflicting results, ranging from strong linkage to no association between MTHFR and psoriasis …”

“…10,11 MTHFR gene variation and differences in presentation of the disease in varying ethnicities or populations have led to discrepancies between studies, and there is little information available on the association between MTHFR polymorphisms and psoriasis vulgaris. 12 Different studies have reported conflicting results, ranging from strong linkage to no association between MTHFR and psoriasis. 9,[12][13][14] The aim of the current study was to explore and describe the effects on homocysteine levels of two single nucleotide polymorphisms (SNPs) in the folateassociated gene MTHFR, and to assess their distribution in psoriatic clinical parameters in a Turkish population.…”

“…12 Different studies have reported conflicting results, ranging from strong linkage to no association between MTHFR and psoriasis. 9,[12][13][14] The aim of the current study was to explore and describe the effects on homocysteine levels of two single nucleotide polymorphisms (SNPs) in the folateassociated gene MTHFR, and to assess their distribution in psoriatic clinical parameters in a Turkish population.…”

Blood homocysteine, folic acid, vitamin B12 and vitamin B6 levels in psoriasis patients

“…Although the MTHFR genotypes in psoriatic patients in Australia (n=310) did not differ from controls, the homocysteine level was found to be higher in 33 patients compared to that in controls 51 . Two meta-analyses carried out on the publications until 2014, which did not include any studies from our country, concluded that there was no relationship between psoriasis and MTHFR polymorphism 52,53 . In brief, both of the arguments stating that there was a different MTHFR polymorphism in patients with psoriasis than in healthy people and that there was a relationship between polymorphism and homocysteine are not conclusive findings.…”