Dietary methionine is involved in the etiology of neural tube defect-affected pregnancies in humans

Research has provided evidence of the role of multivitamin supplementation in the prevention of neural tube defects (NTD). Failure of the neural tube to close is one of the most frequent and severe human developmental defects . The etiology of NTD is complex, encompassing genetic, dietary and environ mental factors. The purpose of this study was to explore the relationship b etween maternal dietary intake of methionine and the risk of having a NTD-a ffected pregnancy. We hypothesized that women with high maternal dietary me thionine intake were at a decreased risk for a NTD. Combinations of methion ine, folate and vitamin B-12 intakes and NTD risk were also examined. Data from a 5-y, population-based, case-control study of 170 NTD-affected pregna ncies and 269 controls were provided by the South Carolina NTD Surveillance , Prevention, and Research Project. There was a 30-55% lower NTD risk among women whose average daily dietary intake of methionine was greater than th e lowest quartile of intake (> 1580 mg/d). The odds ratios associated with the three quartiles of methionine intake > 1580 mg/d after adjusting for en ergy, race and body mass index were 0.72 (P <0.07), 0.68 (P <0.07) and 0.45 (P <0.06), respectively. These findings indicate that a reduction in the r isk of having a NTD-affected pregnancy is associated with maternal dietary intake of methionine (3 mo pre- to 3 mo postconception). This finding is co nsistent with the hypothesis that methionine plays a role in the etiology o f NTD and suggests the need for further research in the area of maternal di et and pregnancy.