Familial translocation t(3;10) (p26.3;p12.31) leading to trisomy 10p12.31 --> pter and monosomy 3p26.3 --> pter in seven members

We report a large family with the simultaneous presence in seven members o fan unbalanced trans location t(3p;10p), resulting in partial trisomy 10p (p12.31?pter) involving 19.3 Mb, and of partial monosomy 3p (p26.3?pter), involving 2.6 Mb. This unbalanced chromosome constitution are likely to be the results of adjacent-1 segregation of the balanced translocation t(3;10)(p26;p12), or could come from alternate segregation having interstitial crossover, found in 13 members of the family. Subjects with the balanced translocation do not present any clinical abnormalities. The presence of many spontaneous abortions suggested that other unbalanced products of the translocation are not viable.