Aneuploidy in neurons

Article By:

McConnell, Michael J. Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia.

Gage, Fred H. Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California.

Last reviewed:2014

DOI:https://doi.org/10.1036/1097-8542.YB150917

A human being develops from one cell at conception. This single cell will grow, duplicate its genome, and then divide into two cells. Each daughter cell will then repeat this process, and some 37 trillion cell divisions will occur before the single cell becomes an individual. An essential requirement of cell division is that the duplicated genome is evenly partitioned between each single cell's two progeny. The genome is organized into chromosomes, and humans have 23 pairs of chromosomes. When human cells divvy up, or segregate, their chromosomes evenly, each daughter cell will have 46 total chromosomes. Sometimes, cells missegregate chromosomes, and daughter cells have more or fewer than 46 chromosomes. Cells with a normal chromosome number are called euploid. In contrast, cells with an abnormal chromosome number are not euploid, so these are called aneuploid.

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