Entry courtesy of
The National Human Genome Research Institute (NHGRI)

Metaphase

The phase of mitosis, or cell division, when the chromosomes align along the center of the cell. Because metaphase chromosomes are highly condensed, scientists use these chromosomes for gene mapping and identifying chromosomal aberrations.

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Dr. Paul Meltzer, of the National Human Genome Research Institute's Laboratory of Cancer Genetics, defines metaphase.