Individuals with 48, XXXY or 49,XXXXY are called variants of Klinefelter Syndrome by P.J.Russell,2010 (i Genetics).
But I read a paper published in 2011 titled:
48,XXYY, 48,XXXY and 49,XXXXY syndromes: not just variants of Klinefelter syndrome.
My question is why the physiological condition...