Thank you for your comments. Testosterone replacement also results in general improvement in behavior and work performance [ 23 ]. Helv Paediat Acta. The majority of known types of chromosomal abnormalities involve sex chromosomes. Behavior and personality The personalities of 47,XXY males are variable.
Of these, 22 pairs are autosomes, which determine our unique biological and physiological features. This tolerance most likely relates to both X inactivation and to the small number of genes on the Y chromosome. Other possible variations include:.
Griffiths, A. A female individual is determined by XX and a male individual is determined by XY. The abnormalities are often hard to recognize at birth and may not be diagnosed until puberty.
Clin Exp Immunol. Hidden category: Inserted articles. In infancy, males with 47,XXY may have chromosomal evaluations done for hypospadias, small phallus or cryptorchidism [ 6 ]. The cause may result from the estradiol to testosterone ratio being severalfold higher than that of karyotypically normal men or possibly due to an increased peripheral conversion of testosterone to estradiol in men with Klinefelter syndrome [ 19 ].
Language development Several longitudinal studies of males with 47,XXY have revealed a tendency for language deficits that often causes academic difficulties during the school years. It was believed to be an endocrine disorder of unknown etiology, until , when Jacobs et al.