Klinefelter se sindroom klinefelters syndrom Klinefelter syndrome Klinefelters syndrome 49,XXXXY syndrome 100160 http://purl.bioontology.org/ontology/SNOMEDCT/275264009 https://en.wikipedia.org/wiki/49,XXXXY https://www.wikidata.org/wiki/Q4638720 An extremely rare aneuploidic sex chromosomal abnormality. It occurs in approximately 1 out of 85,000 to 100,000 males. This syndrome is the result of maternal non-disjunction during both meiosis I and II. It was first diagnosed in 1960. Fraccaro syndrome Klinefelter syndrome XXXXY Klinefelter syndrome, XXXXY Klinefelter's syndrome XXXXY Klinefelter's syndrome, XXXXY XXXXY syndrome 49,XXXXY