Quantitative assessment of the association between MTHFR C677T polymorphism and colorectal cancer risk in East Asians.
A great number of studies regarding the association between MTHFR C677T polymorphism and risk of colorectal cancer (CRC) in East Asians were published, but the results were inconsistent. Thus, a meta-analysis was performed to investigate the association. PubMed, Embase, and CBM databases were searched for eligible publications. Pooled odds ratios (ORs) with 95 % confidence intervals (95 % CIs) were calculated using random or fixed effect models. Finally, 24 case-control studies with a total of 7,230 CRC cases and 9,285 controls were included. Meta-analyses of a total of 24 studies showed there was a statistically significant association between MTHFR C677T polymorphism and decreased CRC risk in East Asians under four genetic models (T versus C, OR = 0.92, 95 % CI 0.85-0.99; TT versus CC, OR = 0.80, 95 % CI 0.69-0.94; TT versus CT/CC, OR = 0.82, 95 % CI 0.71-0.95; TT/CT versus CC, OR = 0.92, 95 % CI 0.86-0.98). The cumulative meta-analyses for the allele contrast (T versus C), homozygote (TT versus CC), dominant (TT/CT versus CC), and recessive (TT versus CT/CC) models all showed a trend of more obvious association as information accumulated by year. Subgroup analyses by country further identified this association in Korea and Japan. This meta-analysis suggests that MTHFR C677T polymorphism is associated with decreased risk of colorectal cancer in East Asians, and MTHFR 677T variant has a protective effect on colorectal cancer.
Institute of Biomedicine and School of Medicine, Tsinghua University, Beijing 100084, China.
Shan
S
Zhong
Jia-He
JH
Yang
Kai
K
Liu
B H
BH
Jiao
Zhi-Jie
ZJ
Chang
D044466:Asian People / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology*; D005202:Asia, Eastern / Q000453:epidemiology; D020022:Genetic Predisposition to Disease; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011379:Prognosis; D012307:Risk Factors
C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)