Aneuploidy

Aneuploidy is a condition where the nucleus of a cell has one or a few chromosomes more or less than the usual number in the species.Species normally have a set number of chromosomes in each individual, and the term "aneuploidy" refers to the chromosome number being different from the usual number for that species. It is a common cause of genetic disorders. Aneuploidy occurs during cell division when the chromosomes do not separate properly between the two cells. Dudek R.W. 2007. High-yield cell and molecular biology. 2nd ed, Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins,  p. 129 

Aneuploidy often causes birth defects and miscarriages.Hassold T; Hall H. & Hunt P. 2007. The origin of human aneuploidy: where we have been, where we are going. Human Molecular Genetics 16, Review Issue 2, p. R203. Birth defects make up about 3% of births in the United States. Among those who survive birth, Down syndrome is the most common form of aneuploidy.Benson J.B. & Haith M.M. (eds) 2009. Diseases and disorders in infancy and early childhood. Academic Press, p. 85 Many with Down syndrome do survive to adulthood. Some cancer cells also have abnormal numbers of chromosomes. The aneuploid theory of cancer suggests that aneuploidy is a cause of cancer rather than a result of it. 

 Related pages 
Trisomy
Polyploidy

 References 

Category:Chromosomes
Category:Genetic disorders