Premature ovarian failure due to tetrasomy X in an adolescent girl

Tetrasomy X associated with premature ovarian failure has been described in a few patients, and the parental origin of the extra X chromosomes has not been investigated so far in this group. A 15-year-old girl with mental retardation and minor physical anomalies showed secondary amenorrhea, high gonadotropin levels, and osteoporosis. Molecular analysis of the fibroblast cells revealed pure 48,XXXX constitution despite 48,XXXX/47,XXX mosaicism in peripheral blood. Analysis of the polymorphic markers (X22, DXYS218, DXYS267, HPRT) on the X chromosome by the quantitative fluorescent polymerase chain reaction (QF-PCR) method demonstrated that the extra X chromosomes were maternal in origin. Conclusion: Patients with tetrasomy X syndrome should be screened for ovarian insufficiency during early adolescence because hormone replacement therapy may be required for prevention of osteoporosis. In order to understand a potential impact of the parental origin of the extra X chromosomes on ovarian development and function, further studies are needed.