N. E. KARACA, E. KARACA, H. ONAY, C. GÜNDÜZ, A. EGEMEN, F. ÖZKINAY

Evaluation of mothers' MTHFR genotype and other risk factors of neural tube defects in their children

Amaç: Nöral tüp defektleri, başlıca spina bifida ve anensefali olmak üzere, sinir sisteminin sık görülen konjenital anomalileridir. Nöral tüp defekti etyolojisi tam anlaşılamamakla beraber, etyolojide genetik ve çevresel faktörler sorumlu tutulmaktadır. Bu çalışmada akraba evliliği, annedeki obesite, annenin folat ve vitamin B12 düzeyleri, ebeveyn yaşı ve annenin metilentetrahidrofolat redüktaz gen polimorfizmleri gibi genetik ve çevresel risk faktörlerinin çocukta nöral tüp defekti gelişimi üzerine etkisinin araştırılması hedeflenmiştir. Ek olarak, annelerin multivitamin kullanımı, eğitim düzeyi, meslek durumu, sosyoekonomik düzey ve doğum şekilleri de incelenmiştir. Gereç ve Yöntem: Nöral tüp defektli çocuğu olan 45 ve sağlıklı çocuğu olan 41 anne çalışmaya alınmıştır. Tüm annelerde serum folat ve vitamin B12 düzeyleri ile metilentetrahidrofolat redüktaz 677C>T ve 1298A>C polimorfizmleri çalışılmıştır. Vücut kitle indeksi ölçülmüştür. Sosyodemografik ve sosyoekonomik özellikler anket uygulanarak değerlendirilmiştir. Bulgular: Nöral tüp defektli çocuğu olan annelerde obesite ve akraba evliliği daha sık, gebelikte multivitamin kullanımı daha az, serum vitamin B12 düzeyi daha düşük ve metilentetrahidrofolat redüktaz 677TT genotipinin daha sık olduğu görülmüştür. Sonuç: Nöral tüp defekti etyolojisinde gebelikte yetersiz multivitamin alımı, akraba evliliği, maternal obesite ve metilentetrahidrofolat redüktaz 677TT genotipinin rol aldığı saptanmıştır.

Nöral tüp defektlerinde annelerde MTHFR gen polimorfizmleri ve diğer risk faktörlerinin değerlendirilmesi

Aim: Neural tube defects (NTDs) are common congenital anomalies of the nervous system, comprising primarily of spina bifida and anencephaly. The etiology of NTDs is complex and the genetic and enviromental factors which appear to be involved in the etiology are imperfectly understood. This study was conducted to investigate the influence of genetic and enviromental factors, namely parental consanguinity, maternal obesity, maternal folate and vitamin B12 levels, parental age and the maternal MTHFR genotype on the risk of NTD in the child. Additionally, maternal multivitamin intake, maternal education and occupation status, socioeconomic levels and the type of delivery were also evaluated. Materials and Methods: Forty-five mothers who had children affected with NTD and forty-one mothers who had healthy children were included in the study. All mothers' serum folate and vitamin B12 levels were measured, and the 677C>T and the 1298A>C polymorphisms of the MTHFR gene were analysed, and body mass index was calculated. A questionnaire was administered to detect the sociodemographic and socioeconomic status in both groups. Results: Comparison of the parameters of both groups revealed that frequencies of maternal obesity, consanguineuos marriages are higher, multivitamin intake and serum vitamin B12 levels are lower, and frequency of MTHFR 677TT genotype is higher in mothers of children with NTD. Conclusion: Parental consanguinity, inadequate multivitamin intake during pregnancy, maternal obesity and the MTHFR 677TT genotype may play a role in the etiology of NTDs.

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