Interaction between maternal periconceptional supplementation of folic acid and reduced folate carrier gene polymorphism of neural tube defects.
OBJECTIVE
To search the interaction between reduced folate carrier gene (RFC1 A80G) polymorphism of children with neural tube defects (NTDs) and maternal periconceptional no supplementation of folic acid. The purpose is to provide the epidemiological evidence for finding genetic marker of NTDs.


METHODS
RFC1 (A80G) genotype was detected using PCR-restricted fragment length polymorphism for the blood DNA of 104 trios with NTDs-affected child, and 100 control families with non-malformed control children. The authors investigated the gene-environment interactions between the offspring RFC1 genotype and maternal periconceptional folic acid supplementation through a case-control study.


RESULTS
It was observed that the offspring with the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to those with the AA genotype (OR = 2.56; 95% CI = 1.04-6.36) in this population under investigation. The risk of mothers who did not take folic acid for having an NTDs-affected infants was 7.69 (95% CI = 2.86-21.75). Among the mothers who did not utilize folic acid supplements, the NTDs risk was 3.30 (95% CI = 1.15-9.65) for offspring with the GG genotype, compared to the reference (AA) genotype. Children who had the GG genotype and whose mothers did not take folic acid had an elevated risk for NTDs (OR = 8.80, 95% CI = 2.86 - 29.82), compared to "offspring with AA or GA genotype" and "maternal folic acid use", the interactive coefficient being 1.45.


CONCLUSIONS
The above findings indicate that the RFC1 genotype (GG) is a possible susceptible gene marker for an increased NTDs risk in Chinese population, and there is a potential gene-nutrient interaction between offspring RFC1 GG genotype and maternal periconceptional intake of folic acid on the risk of NTDs. However,the sample size of this study was limited, a larger sample of population-based study is required to pursue the initial observation.
Pei
Li-jun
LJ
Institute of Reproductive and Child Health, National Reference Laboratory on Reproductive Health Research, Ministry of Health, Peking University, Beijing, 100083, PR China. Peilj@ncmih.bjmu.edu.cn
Zhu
Hui-ping
HP
Li
Zhi-wen
ZW
Zhang
Wei
W
Ren
Ai-guo
AG
Zhu
Jiang-hui
JH
Li
Zhu
Z
D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics*; D009436:Neural Tube Defects / Q000235:genetics* / Q000517:prevention & control; D011110:Polymorphism, Genetic / Q000235:genetics*; D058978:Reduced Folate Carrier Protein; D014803:Vitamin B Complex / Q000008:administration & dosage
D026901:Membrane Transport Proteins; D058978:Reduced Folate Carrier Protein; C548699:SLC19A1 protein, human; D014803:Vitamin B Complex; D005492:Folic Acid