👉 Monosemy, also known as monosomy, is a condition in which one of two or more chromosomes from an individual's somatic cells does not contain a complete set of its genetic material. This means that there are no copies of each of the three primary sex chromosomes present in the cell. In humans, for example, if one of the two sex chromosomes (X or Y) is missing, it would be considered monosemitic. In this case, a person would have