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A cell with a missing chromosome from a homologous pair, for example Turner syndrome in which one of the X chromosomes is missing.

Use in clinical context

Monosomy is a type of aneuploidy. For most chromosome pairs the embryo is not viable if one of the chromosomes is missing at fertilisation. The exception to this are the sex chromosomes. A single X chromosome can perform most functions on its own because it has evolved to do so in males where the Y chromosome has limited functional genes. Turner syndrome occurs when an individual has only a single X chromosome. As with other aneuploidies, monosomy can occur in cancer influencing tumour growth and progression, and response to therapyMonosomy can be identified using karyotyping or sequencing.

Last updated on 29th May, 2019