Phenytoin Teratogenicity in the Primary and Secondary Mouse Embryonic Palate Is Influenced by the H-2 Histocompatibility Locus

Abstract

Abstract

Inbred and congenic strains of mice have been studied for susceptibility to phenytoin-induced cleft lip with or without cleft palate (CLP) and isolated cleft palate (CP). The role of genes linked to the H-2 complex on chromosome 17 has been confirmed. Congenic strains with the A background have identical levels of spontaneous CLP, whereas those strains having the A background with the H-2 ^a haplotype have significantly higher rates of induced CLP than their congenic partners with the H-2 ^b or H-2 ^s haplotype. No such significant difference in the degree of CLP produced by phenytoin is demonstrable in strains with the B background. Rates of isolated CP produced by phenytoin are significantly higher in strains with H-2 ^a than in their congenic partner strains with either H-2 ^b or H-2 ^s, whether the background is A or B.