Kleinfelter Syndrome is a genetic disorder of type XXY.
Subjects of Kleinfelter Syndrome are frequently subject to various gender identity issues. In addition they are frequently taller than average during childhood and puberty and may suffer from various developmental and learning issues.
Those afflicted with Kleinfelter Syndrome present anatomically as male and are reproductively sterile.
This condition is well-documented on the web, and a web search is suggested for those wanting more detail on this subject.