47,XXX syndrome http://purl.bioontology.org/ontology/MESH/C535318 http://purl.bioontology.org/ontology/SNOMEDCT/35111009 https://en.wikipedia.org/wiki/Triple_X_syndrome https://www.wikidata.org/wiki/Q510912 A condition characterized by the presence of an extra X chromosome in each cell of a person who is XX. Those affected are usually taller than average, but otherwise unaffected physically, other than in terms of fertility. Occasionally there are learning difficulties, decreased muscle tone, seizures, or kidney problems. XXX syndrome chromosome XXX syndrome triple X syndrome triple-X chromosome syndrome triple-X syndrome trisomy X syndrome chromosomal gain syndrome 47,XXX allosomal chromosomal syndrome The Complete Dictionary of Sexology