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Genetics and Criminology - A New Concept

NCJ Number
QUADERNI DI CRIMINOLOGIA CLINICA Volume: 17 Issue: 4 Dated: (October/December 1975) Pages: 487-517
C R Jeffery; I A Jeffery
Date Published
32 pages
Correlations between chromosomal abnormalities in human males and some types of deviant behavior (e.g., aggression) are strongly suggested by recent genetic research.
Early criminology theoreticians, especially the 19th century Italian school, postulated biological and heredity factors as crime determinants, but their hypotheses were rejected in the 1920's by sociological criminologists who attributed deviance entirely to societal and environmental influences. However, the earlier biological determinism was given new credence, in the late 1960's, when geneticists found that, while normal human males have an XY sex chromosome (as contrasted to the XX female genotype) an extra Y chromosome is often found in violent male criminals. The XYY (supermale) chromosomal syndrome may act on the brain's limbic system (which regulates man's most primitive drives, including his impulses toward violence) and somehow help trigger violent criminal acts. Criminal behavior can admittedly also be set off by environmental conditions, and be learned through the power of example. It is also true that genes do not act directly upon behavior, but rather on the brain's behavior mechanisms (i.e., receptors/integrators/effectors) and upon the endocrine system. Yet the correlation between the XYY syndrome (accompanied by abnormal electroencephalographic and electrocardiographic readings; and by physical abnormalities, e.g., body size, thyroid dysfunctions, and sensory alterations of taste and smell) is frequent enough to call for consideration by objective criminologists, especially in the formulation of crime prevention measures. An interdisciplinary apprach to criminological research is needed with emphasis on the interaction of genetics, brain functions, and environment. Violent criminals who are also XYY carriers must be intensively studied to ascertain to what extent genetic instructions mold the behavior of such individuals versus the learning process and societal and environmental factors. Criminologists must accept the idea that learning and genetics are not alternate, but, rather, interacting variables in human behavior. Italian, French, English, Spanish, and German abstracts are provided. Seventy-five references and a table summarizing institutional research concerning the 47 XYY karyotype, are appended. --in Italian.