[Postaxial polydactyly: a symptom of partial trisomy of the long arm of chromosome 13. Two new observations with 46, XX, t (22;13) (q13;q31) and 46, XY, Dup (13) (pter-q34::q22-qter) (author's transl)].

Postaxial polydactyly represents an important manifestation of distal (partial) trisomy 13. We report on 2 patients with different chromosomal aberrations who share also mental deficiency, abnormal EEG, moderate dilatation of the 3rd ventricle and craniofacial dysmorphy.