Balanced reciprocal (X;9) translocation in a girl with primary amenorrhea.

An 18-year-old girl with an X-autosome translocation t(X;9)(q22;q12) had primary amenorrhea without other manifestations of the Turner syndrome. X-replication and GALT activity studies showed that both of the two translocated X fragments and adjacent autosomal segments are active. An explanation is offered to account for the relationship between the abnormal karyotype and the phenotype. It is suggested that a position effect and/or an effect exerted between reactivation of the X chromosome and oocyte meiosis may be important in the pathogenesis of the amenorrhea.