XYY syndrome

(redirected from XYY Karyotype)
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XYY syndrome

the theory that a man with an extra Y-chromosome is predisposed towards violence and aggression and hence the basis, usually unsuccessful, for a defence argument.
References in periodicals archive ?
Men with a 47, XYY karyotype are generally fertile.[12] However, the association between 47, XYY and fertility problems has been reported by several studies with an increased incidence of chromosomally abnormal spermatozoa of men with 47, XXY syndrome.[13],[14] The extra Y chromosome showed an increased risk to deliver to the offspring due to the high prevalence of hyperhaploid sperm.[15] A recent study demonstrated a higher frequency of aneuploid sperm of 37.2-37.8%, with approximately one-half of the abnormalities caused by sex chromosomal aneuploidy.
Despite the XYY karyotype, spermatogenesis in affected men results mainly in 23, X and 23, Y sperm as the supernumerary Y is eliminated during meiosis.