<P> In December 1969, Lore Zech at the Karolinska Institute in Stockholm first reported intense fluorescence of the A T - rich distal half of the long arm of the Y chromosome in the nuclei of metaphase cells treated with quinacrine mustard . In April 1970, Peter Pearson and Martin Bobrow at the MRC Population Genetics Unit in Oxford and Canino Vosa at the University of Oxford reported fluorescent "male" sex chromatin bodies in the nuclei of interphase cells in buccal smears treated with quinacrine dihydrochloride, which could be used to screen for Y chromosome aneuploidies like 47, XYY . </P> <P> In June 1970, The XYY Man was published--the first of seven Kenneth Royce spy novels whose fictional tall, intelligent, nonviolent XYY hero was a reformed expert cat burglar recruited by British intelligence for dangerous assignments--and later adapted into a thirteen - episode British summer television series broadcast in 1976 and 1977 . In other fictional television works, a January 1971 episode "By the Pricking of My Thumbs ..." of the British science fiction TV series Doomwatch featured an XYY boy expelled from school because his genetic condition led him to be falsely accused of nearly blinding another boy, a November 1993 episode "Born Bad" of the American police procedural TV series Law & Order portrayed a 14 - year - old XYY sociopathic murderer, and the May 2007 season finale episode "Born To Kill" of the American police procedural TV series CSI: Miami depicted a 34 - year - old XYY serial killer . The false stereotype of XYY boys and men as violent criminals has also been used as a plot device in the horror films Il gatto a nove code in February 1971 (dubbed into English as The Cat o' Nine Tails in May 1971) and Alien 3 in May 1992 . </P> <P> In December 1970, at the annual meeting of the American Association for the Advancement of Science (AAAS), its retiring president, geneticist H. Bentley Glass, cheered by the legalization of abortion in New York, envisioned a future where pregnant women would be required by the government to abort XYY "sex deviants". Mischaracterization of the XYY genetic condition was quickly incorporated into high school biology textbooks and medical school psychiatry textbooks, where misinformation still persists decades later . </P> <P> In the late 1960s and early 1970s, screening of consecutive newborns for sex chromosome abnormalities was undertaken at seven centers worldwide: in Denver (Jan 1964--1974), Edinburgh (Apr 1967--Jun 1979), New Haven (Oct 1967--Sep 1968), Toronto (Oct 1967--Sep 1971), Aarhus (Oct 1969--Jan 1974, Oct 1980--Jan 1989), Winnipeg (Feb 1970--Sep 1973), and Boston (Apr 1970--Nov 1974). The Boston study, led by Harvard Medical School child psychiatrist Stanley Walzer at Children's Hospital, was unique among the seven newborn screening studies in that it only screened newborn boys (non-private - ward newborn boys at the Boston Hospital for Women) and was funded in part by grants from the NIMH Center for Studies of Crime and Delinquency . </P>

Males who have xyy chromosomes are referred to as