[1][2] In 1959, five days after Jérôme Lejeune described the trisomy-21[3] in Down syndrome, basing himself off Marthe Gautier's work,[4] Jacobs and John Strong described an additional X chromosome in male patients (the 47,XXY karyotype)[5] also known as Klinefelter syndrome, as Harry Klinefelter had already diagnosed the symptoms in 1942.
[8] However, the experimental design had many flaws, including small sample sizes, biased sampling, and poor definition of the phenotype "aggression", resulted in the mischaracterization of XYY individuals as aggressive and violent criminals, which led the path for many biased studies on height-selected, institutionalised XYY individuals in the following decades.
[2] In 1981, she received the William Allan Memorial Award from the American Society of Human Genetics.
[1][12] She was the first recipient of the KS&A Patricia Jacobs Lifetime Achievement Award from the US charity Knowledge Support & Action.
[13] In February 2010, Jacobs was elected as a member of the United States National Academy of Sciences, the induction ceremony took place in April.