Maternal Environmental Effects in Mice with Spontaneous Cleft Lip and Palate

Abstract

OBJECTIVE: This study was to investigate the maternal environmental effects in mice with spontaneous cleft lip and palate (CLP). METHODS: As parent A; A/WySn, CLP-susceptible and B 6; C 57 BL/6 CLP-resistant strain mice, F1(A×B6)andF1(B6×A) mice were obtained in which the mating mother was A strain and B 6 strain, respectively. N 2 backcross mice were obtained from A×F1(A×B6)and A×F1(B 6×A) in which the mating mother was both A strain and F1(A×B6)×A and F1(B6×A)×Ain which the mating mother was both F 1 strain. A caesarean section was done on the 17th and 18th gestational day at which time the implantation, resorption and litter size were recorded for F 1 and A as mother, respectively. Each alive N 2 backcross fetus was checked for the presence of CLP. RESULTS: 430,551,667 and 1071 N 2 backcross mice for A×F1(A×B6), A×F1(B6×A), F1(A×B6)×AandF1(B6×A)×A groups were obtained, respectively. The resorption rate in the N2[A×F1] group was significantly higher than the N2[F1×A] group. The fetus survival rate in the N 2[F 1xA] group was significantly higher than the N2[A×F1] group. The incidence rates of bilateral and unilateral CLP in the N2[A×F1] group were significantly higher than the N2[F1×A] group. There was a higher frequency of bilateral CLP for N2[AxF1] group than unilateral CLP. The pregnancy rate of the fetuses having CLP in A/WySn mothers was significantly higher than the F 1 mothers. CONCLUSION: These results suggested that the occurrence of CLP was influenced by maternal environmental effects during pregnancy. A/WySn mother showed a poor environment effect for the embryos development.