Experimental study on cleft lip and/or palate: fetuses of A/J mice in uteri of F1 hybrid mothers using ovarian transplantation.

The A/J inbred strain of mice spontaneously develops cleft lip and/or palate (CL/P). Ovarian transplantation and several test-matings with C57BL/6 strain mice (0% CL/P) were performed to investigate a relationship between mother and fetus in regard to this order. The fetuses obtained showed that regardless of whether the genetic background of the mother was A/J or F1, CL/P was produced only in cases where the fetuses were genetically pure A/J. CL/P frequency was 7.46% in A/J fetuses developed in A/J mothers; it was 5.88% in F1 mothers with transplanted A/J ovaries. Isolated cleft palate (CP) and cleft lip with cleft palate (CLP) were found in A/J mothers. However, the frequency of CP was lower in F1 mothers than in A/J mothers. These results suggest that the occurrence of CLP depends more on the genetic constitution of the fetus than on maternal environmental factors, and the occurrence of CP was influenced by the mother's condition.