RESUMEN

BACKGROUND: This report describes the sixth case of an unusual association: Down syndrome with achondroplasia. It also analyzes the effects of both of these disorders on patient phenotype. METHODS: A male infant was evaluated for Down syndrome. His appearance also suggested a diagnosis of achondroplasia. The child was evaluated by physical examination, radiography, cytogenetic study, and mutation analysis. RESULTS: Chromosome analysis showed a karyotype of 47,XY,+21 in all 30 cells analyzed. Radiographic examination showed typical findings of achondroplasia, such as disproportionately large skull, shortening of limb segments, and lumbar lordosis. FGFR3 screening showed a heterozygous G1138A mutation. CONCLUSIONS: The interaction of these two distinct genetic disorders in the same patient produces a phenotype typical of each syndrome with some overlapping signs. This case represents de novo origin of two disorders that both may be parental-age related.

Asunto(s)

Acondroplasia/complicaciones , Síndrome de Down/complicaciones , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Acondroplasia/genética , Acondroplasia/patología , Sustitución de Aminoácidos , Síndrome de Down/genética , Síndrome de Down/patología , Síndrome de Down/psicología , Genotipo , Humanos , Recién Nacido , Cariotipificación , Masculino , Edad Materna , Mutación Missense , Edad Paterna , Fenotipo , Mutación Puntual