The first published report of a man with a 47,XYY karyotype was by internist and cytogeneticist Avery Sandberg and colleagues at Roswell Park Memorial Institute in Buffalo, New York in 1961. It was an incidental finding in a normal 44-year-old, 6 ft. [183 cm] tall man of average intelligence who was karyotyped because he had a daughter with Down syndrome. Only a dozen isolated 47,XYY cases were reported in the medical literature in the four years following the first report by Sandberg.