RT Journal Article SR Electronic T1 An epidemiological and genetic study of facial clefting in France. I. Epidemiology and frequency in relatives. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 8 OP 15 DO 10.1136/jmg.19.1.8 VO 19 IS 1 A1 Bonaiti, C A1 Briard, M L A1 Feingold, J A1 Pavy, B A1 Psaume, J A1 Migne-Tufferaud, G A1 Kaplan, J YR 1982 UL http://jmg.bmj.com/content/19/1/8.abstract AB The frequencies of cleft lip with or without cleft palate (CL(P)) and isolated cleft palate (CP) have been estimated in France to be 0.082% and 0.035%, respectively, after exclusion of malformation syndromes. A genetic and epidemiological study has been carried out on 468 patients with CL(P) and 163 with CP. The results are given in detail and some specific points are discussed: the apparently low incidence in France, the relationship between sex ratio and abortion rates, the maternal effects, and the possibility of an association between CL(P) and CP.