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​Monosomy
Definition
Monosomy refers to the condition in which only one chromosome from a pair is present in cells rather than the two copies usually found in diploid cells. When cells have one chromosome from a pair plus a portion of the second chromosome, this is referred to as partial monosomy. Monosomy, or partial monosomy, causes certain human diseases such as Turner syndrome and Cri du chat syndrome.
![Monosomy](/sites/default/files/media/images/tg/Monosomy.jpg)
Narration
Monosomy. Formally, monosomy refers to the status of a cellular genome where one copy of a chromosome pair is absent. The term has also been expanded to situations where a segment of a chromosome, perhaps even just a single gene, is absent from a copy of a chromosome.
![Leslie Biesecker](/sites/default/files/media/images/2020-01/Biesecker_Les.jpg)
Director & NIH Distinguished Investigator
Center for Precision Health Research