Venkateshwari, ASrilekha, ABegum, AshrafunnisaSujatha, MRani, P UshaSunitha, TNallari, PratibhaJyothy, A2012-10-292012-10-292010-04Venkateshwari A, Srilekha A, Begum Ashrafunnisa, Sujatha M, Rani P Usha, Sunitha T, Nallari Pratibha, Jyothy A. Clinical and behavioural profile of a rare variant of klinefelter syndrome-48, XXXY. Indian Journal of Pediatrics. 2010 Apr; 77(4): 447-449.http://imsear.searo.who.int/handle/123456789/142557Klinefelter’s syndrome is a sex chromosomal aneuploidy caused by an addition of X chromosome in males (47,XXY).Variants of this syndrome with X and Y polygamy are of rare occurrence. Here we describe a rare case of 48, XXXY Klinefelter’s variant from South India with a reported incidence of 1 per 17,000 to 1 per 50,000 male births. The presence of an extra X chromosome/s in these individuals has a great impact on the physical and cognitive functions, which could be attributed to gene dosage effects and genes involved in neurogenic development.enKlinefelterMosaicismKaryotypeFISHGene dosage effectsAneuploidyChildDevelopmental Disabilities --complicationsHumansIn Situ Hybridization, FluorescenceKlinefelter Syndrome --complicationsKlinefelter Syndrome --diagnosisKlinefelter Syndrome --geneticsMaleArticle