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 (TS) for more than four decades. A large body of cytogenetic data indicates that most TS features are due to reduced dosage of genes on the short arm of the X chromosome (Xp). Phenotype mapping studies using molecular cytogenetic and genetic techniques are beginning to localize the Xp genes that are important for various TS features, and a comprehensive catalog of candidate genes is becoming available through the Human Genome Project and related research. 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 gene involved in short stature and is being applied to premature ovarian failure and other TS phenotypes.