Two cases of partial trisomy 10q syndrome due to a familial 10;20 translocation

We describe an eleven day-old boy and his first degree double cousin who bo th have distal trisomy 10q syndrome. Their cytogenetic analysis using GTG-b anding showed an unbalanced translocation 46, XY, -20, +der(20), t(10;20)(q 22.3, p11) mat and 46, XX, -20, +der(20), t(10;20)(q22.3, p11) mat. The tra nslocation was confirmed by FISH. We have found balanced translocation t(10 ;20)(q22.3; p11) with cytogenetic and FISH studies in the mothers and mater nal grandfather of these children. Our cases had typical craniofacial and v isceral anomalies of this syndrome. However case 1 had an agenesia of corpu s callosum which was not previously described and case 2 had hypertrophied cardiomyopathy and cliteromegaly which were previously described as rare an omalies for this syndrome.