[Trisomy of the distal 15q region due to familial balanced translocation t(15;16)(q24;p13) and unusual mosaicism in the mother of the proband].

Clinic-cytogenetic analysis of the patient with distal 15q trisomy is presented. Proband's mother and grandmother are carriers of the balanced translocation t (15; 16) (q24; p13). Phenotypically normal proband's mother has a second cell clone with repaired marker chromosome 15 which participates in the balanced translocation of the main cell line. It is supposed possible to repair translocated human chromosomes as a result of mitotic recombination process.