MedlinePlus Medical Encyclopedia: Chromosomes and DNA

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Chromosomes and DNA

Humans have 46 chromosomes. There are a total of 23 pairs of chromosomes or 46 total chromosomes. Chromosomes are made up of long strands of DNA which contain all the body’s genes.

Update Date: 7/25/2007

Updated by: Chad Haldeman-Englert, MD, Division of Human Genetics, Children's Hospitalof Philadelphia, Philadelphia, PA. Review provided by VeriMed HealthcareNetwork.

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