Iniencephaly is an extremely rare neural tube defect characterized by the triad of fixed retroflexion of the head, variable degrees of cervical lordosis and dysraphism, and an occipital bone defect involving the foramen magnum. Incidence ranges from 0.1 to 10 in 10,000. Although there have been cases of iniencephaly reported as an isolated anomaly, it very rarely occurs alone. We report here a ...

Mouse embryos homozygous for the mutant gene Loop-tail (Lp) are characterized by craniorachischisis, an open neural tube extending from the midbrain to the tail. In the present study, experimental chimeric mice containing mixtures of genetically mutant (from Lp/+ x Lp/+ matings) and genetically normal cells were produced. Our aim was to determine whether a 'rescue,' phenotypic gradient, or inte...

A body of convincing evidence demonstrates that periconceptional folic acid supplements are associated with a reduction in the risk for first occurrences of neural tube defect and for recurrence of neural tube defects among women with a previously affected pregnancy. The mechanism(s) of this protective effect are unknown, and although the effect can be seen with folate doses between 0.4 and 4 m...

Maternal supplementation with folic acid is known to reduce the incidence of neural tube defects (NTDs) by as much as 70%. Despite the strong clinical link between folate and NTDs, the biochemical mechanisms through which folic acid acts during neural tube development remain undefined. The Mthfd1l gene encodes a mitochondrial monofunctional 10-formyl-tetrahydrofolate synthetase, termed MTHFD1L....

Neural tube defects are serious congenital malformations which can be prevented by periconceptional folic acid supplementation. We hypothesize that folic acid provides the methyl group used for post-translational methylation of arginine and histidine in the highly conserved regulatory domains of the cytoskeleton and that these are required for neural tissue differentiation. Presumptive neural t...

Chimerism is rare in humans and is usually discovered accidentally when a 46,XX and 46,XY karyotype is found in a same individual. We describe a malformed female infant with neural tube defect (NTD) and a 47,XY,+21[5]/46,XX[30] karyotype.