EVIDENCE FOR AN ASSOCIATION BETWEEN MARKERS ON CHROMOSOME 19Q AND NON-SYNDROMIC CLEFT-LIP WITH OR WITHOUT DEFT PALATE IN 2 GROUPS OF MULTIPLEX FAMILIES

It has been reported that BCL3 on chromosome 19q, or a nearby gene, ma y play a role in the etiology of nonsyndromic cleft lip with or withou t cleft palate (NSCL/P) in some families. We tested 30 USA and 11 Mexi can multiplex NSCL/P families for four markers on chromosome 19q: D19S 178, APOC2/AC1, APOC2/007, and BCL3. While likelihood-based linkage an alysis failed to show significant evidence of linkage, the transmissio n disequilibrium test indicated highly significant deviation from inde pendent assortment of allele 3 at the BCL3 marker in both data sets (U SA:P = 0.001; Mexican: P = 0.018: both combined: P < 0.001) and for al lele 13 of the D19S178 marker in the Mexican data set (P = 0.004). The se results support an association, possibly due to linkage disequilibr ium, between chromosome 19 markers and a putative NSCL/P locus.