Molecular analysis of genes on Xp controlling turner syndrome and premature ovarian failure (POF)

Monosomy X has been known to be the chromosomal basis of Turner syndrome (T S) for more than four decades. A large body of cytogenetic data indicates t hat most TS features are due To reduced dosage of genes on the short arm of the X chromosome (Xp). Phenotype mapping studies using molecular cytogenet ic and genetic techniques are beginning to localize the Xp genes that are i mportant for various TS features, and a comprehensive catalog of candidate genes is becoming available through the Human Genome Project and related re search. It is now possible to assess the contributions of individual genes to the TS phenotype by mutational analysis of karyotypically normal persons with specific TS features. This strategy has succeeded in identifying a ge ne involved in short stature and is being applied to premature ovarian fail ure and other TS phenotypes.