Familial premature ovarian failure due to an interstitial deletion of the long arm of the X chromosome.

We describe a family in which four women had menstrual irregularities and a partial deletion of the long arm of the X chromosome (Xq). Three of the four women had premature ovarian failure (at the ages of 24 to 37 years). Chromosome-banding studies initially suggested that a terminal portion of Xq was deleted. However, DNA-hybridization studies showed that an interstitial portion of Xq was deleted and that the affected women had a 46,XX,del(X)(pter-q21.3::q27-qter) karyotype. These findings help clarify the role of Xq in ovarian function and indicate that the accurate description of such abnormalities requires a combination of cytogenetic and DNA-hybridization analysis.