CLINICAL OUTCOMES OF ADJACENT-1 SEGREGATION IN A FAMILIAL TRANSLOCATION T(8-18)(P21.3-P11.23)

We report a reciprocal translocation t(8;18)(p21.3;p11.23) in which bo th unbalanced products of adjacent 1 segregation were observed within a family. The proband was originally referred because of short stature and a webbed neck, but further investigations showed that she had men tal retardation and a congenital heart defect, and had inherited an un balanced form of the maternal translocation, 46,XX,der(8)t(8;18)mat. T he proband's sister spontaneously aborted an 11 week fetus with multip le major system malformations, which was found to have a 46,XY,der(18) t(8;18)mat karyotype. The phenotypic findings of the affected subjects are discussed.