Genetic Variants in the Methylenetetrahydrofolate Reductase Gene in Egyptian Children with Conotruncal Heart Defects and their Mothers
Aim: This study aimed at evaluation of MTHFR 677C/T and 1298A/C polymorphisms in MTHFR gene as maternal risk factors in conotruncal heart defects (CTDs).
Material and Methods: Thirty cases with CTDs and their mothers and thirty control children and their mothers were studied. Medical and nutritional histories for all mothers were taken with emphasis on folate intake. The mutations in MTHFR gene are a C to T substitution at base pair 677 and a A to C at base pair1298 were investigated by polymerase-chain reaction, followed by restriction enzyme digestion and detection by electrophoresis.
Results: Folic acid intake was below the recommended daily allowance in case mothers compared to control mothers. No significant difference between patients and control group or their mothers regarding MTHFR gene polymorphisms at exon 4. Significant difference between case and control groups and between their mothers regarding MTHFR gene polymorphisms at exon 7. Homozygous genotype frequencies of MTHFR at position 1298 was significantly higher in cases and their mothers with an odds ratio 56 (95% confidence interval 10.3-303.7).
Conclusion: Egyptian population may have high incidence of MTHFR polymorphism at exon 7 rather than at exon 4. Preconception folate intake might decrease MTHFR polymorphism at exon 7 and decrease risk of CTD.
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