New Zealand white mice: an experimental model of exencephaly

This is the initial report of an unusually high incidence of exencephaly in inbred New Zealand White (NZW) mice and the congenic NZW-xid strain, in which animals are homozygous for the recessive X-linked immune deficiency (xid) gene. The predominant expression of exencephaly in female pups and a disproportionate decrease in numbers of female pups in litters suggested that exencephaly was part of a continuum of lethal defects expressed preferentially in females. Genetic influence in the expression of exencephaly in NZW mice was postulated because environmental cohort controls did not express this defect. NZW mice are an additional model for studying the pathogenesis of neural tube defects.