%0 Journal Article
%T A review of trisomy X (47,XXX)
%A Nicole R Tartaglia
%A Susan Howell
%A Ashley Sutherland
%A Rebecca Wilson
%A Lennie Wilson
%J Orphanet Journal of Rare Diseases
%D 2010
%I BioMed Central
%R 10.1186/1750-1172-5-8
%X Trisomy X (47,XXX) is a sex chromosome aneuploidy condition in which females have an extra X chromosome, compared to the 46,XX karyotype in typical females. It was first described in 1959 in a 35-year-old woman with normal intellectual abilities who presented with secondary amenorrhea at 19 years of age [1]. Since the initial description, only several hundred cases have been described, identifying a variety of associated developmental, psychological, and medical features. Most of the background literature on trisomy X comes from longitudinal prospective studies of females identified by newborn screening and followed into young adulthood. These studies were conducted in the 1970's and 80's at multiple centers across the U.S., Canada, and the U.K. [2-5]. While newborn screening studies have demonstrated that the incidence of trisomy X is approximately 1/1000 female births, only approximately 10% of cases are ascertained clinically. There is considerable variation in the phenotype, with some individuals very mildly affected and others with more significant physical and psychological features. This manuscript reviews the current literature available describing features associated with trisomy X, with recognition that much of the literature is based on small sample sizes and clinical ascertainment of patients, and does not likely represent the full spectrum of females with trisomy X. However, review of the current knowledge is necessary to provide a summary of background and treatment recommendations for patients and professionals, and to highlight the many areas of need for additional research in trisomy X.Trisomy X is also commonly known as:47,XXXTriple X, orTriplo-XOriginally described as the "superfemale" in 1959, trisomy X occurs in approximately 1 in 1,000 female births, however, it is estimated that only approximately 10% of cases are diagnosed [6]. In identified cases, diagnosis occurs through prenatal amniocentesis or chorionic villi sampling (CVS), or in the po
%U http://www.ojrd.com/content/5/1/8