Achondroplasia with 47, xxy karyotype: a case report of the neonatal diagnosis of an extremely unusual association

Background: The association of achondroplasia and Klinefelter syndrome is extremely rare. To date, five cases have been previously reported, all of them diagnosed beyond the postnatal period, and only one was molecularly characterized. We describe the first case of this unusual association diagnosed...

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Detalles Bibliográficos
Autores: Ros Pérez, Purificación, Regidor, Francisco J., Colino, Esmeralda, Martínez-Payo, Cristina, Barroso, Eva, Heath, Karen Elise
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/662254
Acceso en línea:http://hdl.handle.net/10486/662254
https://dx.doi.org/10.1186/1471-2431-12-88
Access Level:acceso abierto
Palabra clave:Achondroplasia
Karyotype
Klinefelter syndrome
Mutation
Prenatal diagnosis
Medicina
Descripción
Sumario:Background: The association of achondroplasia and Klinefelter syndrome is extremely rare. To date, five cases have been previously reported, all of them diagnosed beyond the postnatal period, and only one was molecularly characterized. We describe the first case of this unusual association diagnosed in the neonatal period, the clinical findings and the molecular studies undertaken. Case presentation: The boy was born at term with clinical and radiological features indicating the diagnosis of achondroplasia or hypochondroplasia combined with the prenatal karyotype of Klinefelter syndrome (47,XXY). Neonatal FGFR3 mutation screening showed that the newborn was heterozygous for the classic achondroplasia G340R mutation. Microsatellite marker analysis showed that the sex chromosome aneuploidy had arisen from a non-disjunction error in paternal meiosis I, with a recombination event in the pseudoautosomal region 1 (PAR1). Conclusion: Specific mutation analysis is appropriate to confirm the clinical diagnosis of achondroplasia for appropriate diagnosis, prognosis, and genetic counseling, especially when the karyotype does not explain the abnormal prenatal sonographic findings. In the present case, a recombination event was observed in the PAR1 region, although recombinational events in paternally derived Klinefelter syndrome cases are much rarer than expected.