XYY syndrome

(redirected from XYY male)
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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 ?
Newsweek asked if criminals were "Born bad?" ("Can a man be born a criminal?") Time headlined a story "Chromosomes and crime." By the early 1970s, at least two films had featured an XYY male criminal, and a series of crime novels had made their focus an XYY hero who struggled with his compulsion to commit crimes.
Jacobs et al., Aggressive Behaviour, Mental Sub-normality and the XYY Male, 208 NATURE 1351, 1352 (1965) ("[T]he finding that 3.5 percent of the population [of institutionalized men] were XYY males must represent a marked increase in frequency by comparison with the frequency of such males at birth."): Herman A.
Generalized macrodontia has been associated with chromosomal anomalies like in XYY males (Klinefelter syndrome) and endocrine disorders such as pituitary gigantism and insulin resistant diabetes.13 Males demonstrate a higher frequency of macrodontia and hyperdontia while females have a greater prevalence
That is to say, the percentage of prison inmates with XYY was higher than the percentage of XYY males in the general population.