1. State of a cell nucleus in which a specific chromosome is represented more than twice. Cells containing three, four, or five homologous chromosomes are referred to, respectively, as trisomic, tetrasomic, or pentasomic.
The information shown above for polysomy is provided by Stedman's.
* Stedman's, part of Lippincott Williams & Wilkins, provide a comprehensive line of health-science publications for healthcare professionals and medical students.