48,XXYY, 48,XXXY and 49,XXXXY syndromes: not just variants of Klinefelter syndrome.
Abstract
Sex chromosome tetrasomy and pentasomy conditions occur in 1:18,000-1:100,000 male births. While often compared with 47,XXY/Klinefelter syndrome because of shared features including tall stature and hypergonadotropic hypogonadism, 48,XXYY, 48,XXXY and 49,XXXXY syndromes are associated with additional physical findings, congenital malformations, medical problems and psychological features. While the spectrum of cognitive abilities extends much higher than originally described, developmental delays, cognitive impairments and behavioural disorders are common and require strong treatment plans. Future research should focus on genotype-phenotype relationships and the development of evidence-based treatments.
CONCLUSION
The more complex physical, medical and psychological phenotypes of 48,XXYY, 48,XXXY and 49,XXXXY syndromes make distinction from 47,XXY important; however, all of these conditions share features of hypergonadotropic hypogonadism and the need for increased awareness, biomedical research and the development of evidence-based treatments.Links
Authors+Show Affiliations
,Section of Neurodevelopmental Behavioral Pediatrics, Department of Pediatrics, University of Colorado School of Medicine, Aurora, USA. Tartaglia.nicole@tchden.org
, , ,Source
MeSH
HumansHypogonadism
Klinefelter Syndrome
Male
Phenotype
Sex Chromosome Disorders
Syndrome
Pub Type(s)
Comparative StudyJournal Article
Research Support, Non-U.S. Gov't
Review
Language
eng
PubMed ID
21342258
