Published in: Personality and individual Differences 13 (1992) 1115-1134
MAJOR GENES OF GENERAL INTELLIGENCE
VOLKMAR WEISS
Summary. - Evidence in favour of the major gene theory of intelligence is stated in summary form.
Empirical distributions from studies on giftedness by Terman and Weiss and data of social mobility can be explained by the existence of a major gene that in the homozygous state is the prerequisite to have an IQ of 130 or higher. Under the assumption of about 10% misclassification of genotypes, family data are in agreement with Mendelian segregation at such a major gene locus.
Elementary cognitive tasks, highly correlated with IQ, are not distributed normally. On the absolute scale of short-term memory capacity (measured in bits), defined as the product of memory span and mental speed, the heterozygotes are intermediate between the homozygotes.
Where there are major genes, there must be an underlying biochemical code, which can be detected. To this aim enzymes, responsible for the regulation of brain energy metabolism and correlated with IQ and social status, should be the target of further research.
From the point of view of evolution, social stratification and the frequency of major genes of intelligence depend upon each other.
Content
THE RELATIONSHIP BETWEEN MATHEMATICAL GIFTEDNESS AND GENERAL INTELLIGENCE
THE EVOLUTION OF A BALANCED POLYMORPHISM FOR HUMAN INTELLIGENCE
A. R. Jensen, Reviewer' Comment, sent to the Editor in Chief H. J. Eysenck, July 1991:
"Whether Weiss' s theory is true or false, which remains a very open question at present, this article seems to me an impressive effort that deserves full exposure to a wide audience. ... In fact, this is the first article I' ve read on a major gene theory of g that has made me think there might possibly be something to it. If it were adequately proved, of course, it would be a truly major advance."
From: Volkmar Weiss [mailto:Volkmar-Weiss@t-online.de]
Sent: Mittwoch, 21.
Januar
2015 10:59
To: 'James.Sikela@ucdenver.edu'
Subject: DUF1120 copy number is
linearly associated with IQ
Dear Professor Sikela:
Yesterday I read in Human Genetics
134 (2015) 67-75 the full text of your publication on „DUF1220
copy number is linearly associated with increased cognitive function
as measured by total IQ and mathematical aptitude scores”,
see
http://www.ncbi.nlm.nih.gov/pubmed/25287832
,
full
text:
https://drive.google.com/file/d/0B3c4TxciNeJZcHg4ek9nWDZGcWs/view?pli=1
As I did catch sight of your Fig. 2 on
page 72 I got deeply impressed, deeply moved, deeply: A linear
association between copy arrayCGH based CON2 copy ratio versus WISC
IQ, extending in the IQ range between 80 and 140. This is a
breakthrough, a centennial breakthrough! My congratulation to your
lab and the cooperating colleagues in New Zealand!
We are aware: What you have discovered is the tip of an iceberg. But
it is the tip!
Your were even clever enough to obtain a patent for the
determination of IQ by this copy number variation (CPV),
see
http://www.google.com/patents/WO2014028768A2?cl=en
DUF means a protein “domain of
unknown function“, containing a number of genes, especially of the
NBPF family, each of it highly polymorphic.
1.
Family studies of the inheritance of CON2 copy ratio and IQ.
There all over the
world thousands of families with more than one gifted in the IQ
range around 130, ready to be
probands.
2.
Representative population data.
Until now it was assumed by the majority
that IQ differences are caused by thousands of genetic polymorphisms
each of it making a small contribution of plus or minus 1, 2
or even3 IQ points. Therefore the environment must play an
important or decisive role. Since decades, whoever hinted that this
thousand-genes-theory did not agree with the data of segregation of
IQ within families, see for example
http://www.v-weiss.de/majgenes.html
, was seen as an obstinate crank. However, in 1972,
already in my dissertation I wrote that the hypothetical major gene
locus of general intelligence could turn out to be a series of
alleles. And in 1992: “Of course, the allele M2 could also be
understood as an abstraction and be in reality a series of n alleles
with small differences; but with a large difference to the M1 allele
or an allele-1 series.”
The difference between the means of the
hypothetical M1M1 and M2M2 is about 30 IQ points. This is the
range, what you found! The other hundreds of polygenes which, of
course, influence mental power under certain circumstances may add
up to IQ differences of 20 points in extreme and rare cases, but
because the minor genes are segregating independently of each
other, their effects as a sum are normally distributed making only a
plus or minus of about 5 IQ-points in the general population.
As we know, in the search for major
effects on IQ all genome-wide association studies (GWAS) were a
failure. Therefore, the conclusion had to be drawn that the
explanation had to be found in previously unexplored regions of the
genome.
Therefore, since some years I suggest to
look for copy number variations and the application of homozygosity
array mapping within families of the highly gifted.
See my monograph “Die Intelligenz und ihre
Feinde” (Intelligence and its Enemies). Graz 2012, page 236 to CPV:
„Da es sehr gut vorstellbar ist, daß diese Art der genetischen
Variabilität auch in der Genetik des normalen IQ eine wichtige Rolle
spielt, konzentrieren sich die Hoffnungen gegenwärtig auf weitere
Erforschung dieser ‚Copy number variations‘ (CPV).“
You and your lab had the knowledge. You
did it. My congratulation.
I wish you the possibility, the freedom and the courage to extend
your findings. You will need it.
(I will forward this email to colleagues
all over the world. I am sure, they will forward this message
further. What is urgently needed is deepening of your
findings, before the enemies of freedom become aware of the
importance of your discovery and are threatening and hampering .)
Sincerely yours
Volkmar Weiss
The mouse has 1 copy of DUF1220, monkeys about
40, chimpanzee 120, homo sapiens nearly 300, with high IQ about 8
more than with low IQ., see