Turner's syndrome is the result of a sporadic chromosomal abnormality. It can result from the non-disjunction of chromosomes in either parent. Over 99% of 45X0 fetuses abort. The risk of recurrence is low.
A minority of individuals are mosaics 45X0/46XX, or more rarely 45XO/45XY.
Turner's syndrome is the only viable monosomy in humans. This is probably because in normal females one copy of the X chromosome in each cell is functionally inactivated in a process called Lyonisation - leading to formation of the Barr body, the absence of which is a diagnostic feature in Turner's. Thus the normal situation in a cell is to have just one functional X chromosome; it is only in certain tissues that the loss matters.
Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.