Homocysteine concentrations and molecular analysis in patients with congenital heart defects.

Background: Congenital heart defects are the result of incomplete heart development and, like many diseases, have been associated with high homocysteine concentration.

Methods: We evaluated homocysteine, folic acid and vitamin B(12) concentrations, and the mutations 677C>T and 1298A>C in MTHFR, 844ins68 in CBS and 2756A>G in MTR genes in 58 patients with congenital heart defects, 38 control subjects, and mothers of 49 patients and 26 controls.

Results: Control and patients presented normal range concentrations for homocysteine (7.66 +/- 3.16 microM and 6.95 +/- 3.12 microM, respectively), folic acid (8.31 +/- 3.00 ng/mL and 11.84 +/- 10.74 ng/mL) and vitamin B(12,) (613.56 +/- 307.57 pg/mL and 623.37 +/- 303.12 pg/mL), which did not differ among groups. For the mothers studied, homocysteine and vitamin B(12) concentrations also did not differ between groups. However, folic acid concentrations of mothers showed significant difference, the highest values being in the group of patients. No difference was found in allele frequencies among all groups studied.

Conclusions: In the studied groups, high homocysteine seems not to be correlated with congenital heart defects, as well as folic acid and vitamin B(12). The mutations studied, in isolation, were not related to congenital heart defects, but high concentration of maternal homocysteine is associated with the presence of three or four mutated alleles.