[Central nervous system malformations and the presence of the MTHFR-C677T mutation in fetal blood].

Purpose: To evaluate the association between central nervous system (CNS) malformations and the C677T-MTHFR mutation in fetal blood.

Methods: A case-control study was conducted to compare the MTHFR-C677T mutation detected in 78 fetuses with CNS malformations and with 100 morphologically normal fetuses. Genomic DNA was extracted and purified from fetal blood using the Wizard® Genomic DNA Purification Kit (Promega Corp., Madison, WI, USA) according to manufacturer's protocol. The polymerase chain reaction (PCR) was used to assay the thermolabile MTHFR-C677T mutation. The γ² and the Fisher's exact tests were used for descriptive analysis and the Wilcoxon test was used for univariate analysis. Logistic regression analysis was performed to identify which variables were predictors of CNS malformation.

Results: Cases and controls were similar regarding maternal characteristics such as age and number of deliveries and abortions. The MTHFR-C677T mutation was detected in 20 cases (25.6%) and in 6 controls in its heterozygous form (OR 10.3; 95%CI 3.3-32.2) and in 6 cases (7.7%) and in 1 control in its homozygous form (OR 12.3; 95%CI 1.3-111.1), and the differences were statistically significant.

Conclusion: The presence of the MTHFR-C677T mutation in fetal blood was consistent with a higher risk of CNS malformations, both in the heterozygous and homozygous forms.