The reigning biometrical paradigm asserts that continuous variation implies the determination of intelligence by many genes with small effects. However, if an appreciable amount of the variability of a continuous trait is due to Mendelian segregation at a single locus, we may speak of the major locus for that trait. In such a case the distributions between the genotypic classes show considerable overlap, caused by error of measurement and environmental influences. As confirmed by Mendelian analysis, Spearman's general factor is the result of genotypes with discrete true scores of central processing time, the heterozygotes being exactly in the mean of the differences of the means of homozygotes.
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References
1.
Geldmacher-von MallinckrodtM.HommelG.DumbachJ.On the genetics of the human serum paraoxonase (EC 3.1.1.2.). Human Genetics, 1979, 50, 313–326.
2.
EllingsonR. J.LathropG. H.Intelligence and frequency of the alpha rhythm. American Journal of Mental Deficiency, 1978, 78, 334–338.
3.
ErtlJ. P.SchaferE. W. P.Brain response correlate of psychometric intelligence. Nature, 1969, 223, 421–422.
4.
JensenA. R.G: Outmoded theory or unconquered frontier?Creative Science and Technology, 1979, 2, 16–29.
OmennG. S.Inborn errors of metabolism: Clues to understanding human behavioral disorders. Behavior Genetics, 1976, 6, 263–284.
7.
ReppN.Zusammenhänge zwischen evozierten Potentialen und der Reaktionszeit mit Intelligenz- und Aufmerksamkeirstests. Dissertation Naturwissenschaftlicher Fachbereich, Mainz, Johannes-Gutenberg-Universität, 1975.
8.
SpearmanC.Autobiography. In MurchisonC. (Ed.), A history of psychology in autobiography. Vol. I. Worcester, MA: Clark Univer. Press, 1930. Pp. 299–331.
9.
WeissV.Die Prüfung von Hypothesen bei den synchron zum Probanden lebenden Seitenverwandten als Methode der Humangenetik. Biometrische Zeitschrift, 1973, 15, 259–270.
10.
WeissV.Diskretheit der genetischen Information, aber Kontinuität der Messwerte—zentrales erkenntnistheoretisches Problem in den Auseinandersetzungen zwischen biometrischer und mendelistischer Genetik. In Philosophie und Naturwissenschaften in Vergangenheit und Gegenwart: Heft 12, Philosophie und Biowissenschaften in der Geschichte. Berlin: Humboldt-Universität, 1978. Pp. 62–68.
11.
WeissV.The heritability of difference scores when environments are correlated. Biometrical Journal, 1979, 21, 171–177.
12.
WeissV.The use of heritabilities of anthropometric measures and performance tests in personnel selection. Gegenbaurs morphologisches Jahrbuch, 1979, 125, 174–177.
13.
Weiss, V., & Mehlhorn, H.-G. Der Hauptgenlocus der Allgemeinen Intelligenz: Diskrete und ganzzahlige Unterschiede in der zentralen Informationsverarbeitungsgeschwindigkeit. Biologisches Zentralblatt, 1980, 99, 297–310.
14.
WisslerC.The correlation of mental and physical tests. Psychology Review Monographs, 1901, 3, No. 6.
