What does monosomy refer to in genetics?

Monosomy refers to a condition in genetics where there is an absence of one chromosome from a pair. In a normal diploid organism, chromosomes exist in pairs, one inherited from each parent. When one of these chromosomes is missing, the organism is said to be monosomic for that chromosome. This can lead to various developmental and health issues depending on which chromosome is absent.

For instance, Turner syndrome is a common example of a condition caused by monosomy, specifically involving the missing X chromosome in females (45, X instead of the typical 46, XX). Understanding monosomy is crucial in genetic studies because it highlights the importance of having complete sets of chromosomes for normal development and functioning.