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Klinefelter's syndrome  is  caused due to the presence of an additional copy of X chromosome resulting into a karyotype of 47, XXY. 

Phenylketonuria is an autosomal recessive disease and results in accumulation of phenylpyruvic acid.

Down's syndrome is due to trisomy of 21 and results in mental retardation.

Turner's syndrome is disorder caused due to the absence of one of the X chromosomes, i.e., 45 with X0,and results in sterile female.