Phenotype of the neural tube defect mouse model bent tail is not sensitive to maternal folinic acid, myo-inositol, or zinc supplementation.

Abstract

Bent tail is a mouse model for X-linked neural tube defects (NTDs) that is characterized by the presence of exencephaly, a delayed posterior neuropore closure, and a tail phenotype. In addition, Bent tail shows laterality defects and increased prenatal mortality. The congenital malformations of this mouse are caused by a submicroscopic deletion that completely encompasses the gene coding for the zinc finger transcription factor Zic3. In this study we investigated the sensitivity of the phenotype of Bent tail to the nutrients folinic acid, myo-inositol, and zinc. These nutrients are thought to be involved in the etiology of NTDs, in combination with a genetic predisposition. The most penetrant phenotype of the Bent tail mouse, the tail malformation, was used as a marker for the nutrient sensitivity of the neural phenotype. The size of the litters and the survival of the offspring, subdivided according to genotype, were analyzed as markers for the nutrient sensitivity of other phenotypic features of Bent tail. In confirmation of earlier studies, we observed the prenatal loss of a number of homozygous females and hemizygous males, as well as the effect of genotype on the tail phenotype of Bent tail. However, periconceptional supplementation of the maternal diet with folinic acid, myo-inositol, or zinc produced no significant effects on either the tail phenotype of the offspring or the size and genotypic composition of the litters. Bent tail appears to be a folinic acid-, myo-inositol-, and zinc-insensitive mouse model for NTDs.