Mitotic disturbances associated with inversion 9qh. A case report.

A 25-year-old female with history of spontaneous abortion and subsequent birth of Down syndrome child was referred for chromosome analysis. Her karyotype revealed 46, XX with pericentric inversion of 9 qh, while her husband was normal with 46, XY chromosomes. Metaphase analysis of the female showed 20.5% cells with premature centromere division, 4% with endoreduplication, 2% with polyploidy and 9.33% aneuploidy. These frequencies were considerably higher as compared to a normal control. These observations suggest that inv (9qh) might have some interchromosomal effect leading to higher incidence of mitotic disturbances, finally resulting in aneuploidy. This predisposition is evident by spontaneous abortion and later birth of a Down syndrome child.