A case of 2q trisomy in a malformed female infant resulting from unbalanced segregation of maternal origin is reported. The mother and one of the proposita's sibs where found to be carriers of balanced translocation 2;17. Two other members in the kindred had died with multiple malformations. The patient's karyotype was 46,XX,-17, + der (17)t(2;17)(q32;q25)mat.