[Translocation t (13:21) (q22:q22) in mother and monosomia 21 and partial trisomy 13 on her son (author's transl)]

Clinical and cytogenetical findings in a case of 21pter leads to 21q22.1 monosomy associated to a partial trisomy 13 are presented. The patient's mother carries a translocation t(13;21) (q22;q22). R-banding has shown that q22 band of an apparently absent chromosome 21 is distally translocated in an extra-chromosome 13 (13q-)+. Therefore the proband's monosomy 21 is not complete, but partial.