Methylenetetrahydrofolate reductase gene polymorphisms and neural tube defects epidemiology in the Slovak population.

Background: Folate deficiency is a known factor contributing to the formation of neural tube defects (NTDs). Many folate metabolism gene variants have been investigated, but only a few substantial associations have been established, the C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene being one of the most significant.

Methods: We determine the MTHFR C677T and A1298C genotypes in 93 Slovak NTD patients and 290 control newborns with respect to sex and ethnicity.

Familial microhydranencephaly, a family that does not map to 16p13.13-p12.2: relationship with hereditary fetal brain degeneration and fetal brain disruption sequence.

Microhydranencephaly (MHAC) is a serious developmental brain anomaly characterized by microcephaly with severe reduction of brain hemispheres and intracranial space filled with cerebrospinal fluid without signs of intracranial hypertension. Clinical findings are very similar to fetal brain disruption sequence - severe microcephaly, scalp rugae, and profound developmental delay; however, although fetal brain disruption sequence is a sporadic condition caused by an external disruptive event, familial cases of MHAC presumably result from a process of progressive brain damage also termed as 'hereditary fetal brain degeneration'. Familial occurrence of this phenotype is very rare - only three reports on four families have been published so far.