Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Akụkọ: A kpọrọ ọrịa a aha Harry Klinefelter, bụ́ onye ya na Fuller Albright na E. C. Reifenstein rụkọrọ ọrụ n'ụlọ ọgwụ Massachusetts General Hospital dị na Boston, Massachusetts, n'afọ 1942, bụ́kwa onye mbụ kọwara ya n'otu afọ ahụ. A bịara mara akụkọ ahụ Klinefelter nyere dị ka ọrịa Klinefelter ka aha ya pụtara na mbụ na akwụkwọ ahụ e bipụtara, na a naghịzi eji dysgenesis nke tubule seminiferous eme ihe. N'iburu aha ndị nchọpụta atọ ahụ n'uche, a na-akpọkwa ya mgbe ụfọdụ ọrịa Klinefelter-Reifenstein-Albright. N'afọ 1956, a chọpụtara na ọrịa Klinefelter na-esite n'otu chromosome ọzọ. Plunkett na Barr chọtara chromatin ahụ nwoke na nwanyị n'ime mkpụrụ ndụ sel nke ahụ. E mere ka nke a dokwuo anya dị ka XXY na 1959 site n'aka Patricia Jacobs na John Anderson Strong. Akụkọ mbụ e bipụtara banyere nwoke nwere karyotype 47,XXY bụ site n'aka Patricia Jacobs na John Strong na Western General Hospital na Edinburgh, Scotland na 1959. A chọtara karyotype a n'ahụ́ otu nwoke dị afọ 24 bụ́ onye na-egosi ihe àmà nke ọrịa KS. Jacobs kọwara nchọpụta ya nke mbụ a kọrọ banyere aneuploidy chromosome nke mmadụ ma ọ bụ nke anụmanụ na 1981 William Allan Memorial Award address.  Ajụjụ: N'afọ dị aṅaa ka Patricia Jacobs na John Anderson Strong mere ka o doo anya na e kwesịrị ịkpọ chromosome ahụ XXY?
Afọ 1959