

Top Genetic Findings of 2012 - bretthardin
http://blog.23andme.com/23andme-research/top-genetic-findings-of-2012

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tokenadult
That reads like a press release. It doesn't read like a serious scientific
discussion of genetic findings. I know a lot of genetics researchers (mostly
behavior genetics researchers.) I'll provide examples below of how the actual
scientists write.

Eric Turkheimer has recently been president of the Behavior Genetics
Association, and he has the very kind habit of posting most of his peer-
reviewed journal articles on his faculty website.

[http://people.virginia.edu/~ent3c/vita1_turkheimer.htm](http://people.virginia.edu/~ent3c/vita1_turkheimer.htm)

Lars Penke is another, younger researcher who posts most of his publications
on his personal website.

[http://www.larspenke.eu/en/publications/publications.html](http://www.larspenke.eu/en/publications/publications.html)

I have the pleasure of meeting many other researchers in human genetics just
about weekly during the school year at the University of Minnesota "journal
club" Psychology 8935: Readings in Behavioral Genetics and Individual
Differences Psychology. From those sources and other sources, I have learned
about current review articles on human behavior genetics that help dispel
misconceptions that are even commonplace among medically or scientifically
trained persons who aren't keeping up with current research.

An interesting review article,

Turkheimer, E. (2008, Spring). A better way to use twins for developmental
research. LIFE Newsletter, 2, 1-5

[http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...](http://people.virginia.edu/~ent3c/papers2/Articles%20for%20Online%20CV/Turkheimer%20\(2008\).pdf)

admits the disappointment of behavior genetics researchers.

"But back to the question: What does heritability mean? Almost everyone who
has ever thought about heritability has reached a commonsense intuition about
it: One way or another, heritability has to be some kind of index of how
genetic a trait is. That intuition explains why so many thousands of
heritability coefficients have been calculated over the years. Once the twin
registries have been assembled, it's easy and fun, like having a genoscope you
can point at one trait after another to take a reading of how genetic things
are. Height? Very genetic. Intelligence? Pretty genetic. Schizophrenia? That
looks pretty genetic too. Personality? Yep, that too. And over multiple
studies and traits the heritabilities go up and down, providing the basis for
nearly infinite Talmudic revisions of the grand theories of the heritability
of things, perfect grist for the wheels of social science.

"Unfortunately, that fundamental intuition is wrong. Heritability isn't an
index of how genetic a trait is. A great deal of time has been wasted in the
effort of measuring the heritability of traits in the false expectation that
somehow the genetic nature of psychological phenomena would be revealed. There
are many reasons for making this strong statement, but the most important of
them harkens back to the description of heritability as an effect size. An
effect size of the R2 family is a standardized estimate of the proportion of
the variance in one variable that is reduced when another variable is held
constant statistically. In this case it is an estimate of how much the
variance of a trait would be reduced if everyone were genetically identical.
With a moment's thought you can see that the answer to the question of how
much variance would be reduced if everyone was genetically identical depends
crucially on how genetically different everyone was in the first place."

The review article "The neuroscience of human intelligence differences" by
Deary and Johnson and Penke (2010) relates specifically to human intelligence:

[http://www.larspenke.eu/pdfs/Deary_Penke_Johnson_2010_-_Neur...](http://www.larspenke.eu/pdfs/Deary_Penke_Johnson_2010_-_Neuroscience_of_intelligence_review.pdf)

"At this point, it seems unlikely that single genetic loci have major effects
on normal-range intelligence. For example, a modestly sized genome-wide study
of the general intelligence factor derived from ten separate test scores in
the cAnTAB cognitive test battery did not find any important genome-wide
single nucleotide polymorphisms or copy number variants, and did not replicate
genetic variants that had previously been associated with cognitive
ability[note 48]."

The review article Johnson, W. (2010). Understanding the Genetics of
Intelligence: Can Height Help? Can Corn Oil?. Current Directions in
Psychological Science, 19(3), 177-182

[http://apsychoserver.psych.arizona.edu/JJBAReprints/PSYC621/...](http://apsychoserver.psych.arizona.edu/JJBAReprints/PSYC621/Johnson%20Current%20Directions%20Psych%20Science%202010%20\(G%20and%20E%20in%20IQ\).pdf)

looks at some famous genetic experiments to show how little is explained by
gene frequencies even in thoroughly studied populations defined by artificial
selection.

"Together, however, the developmental natures of GCA [general cognitive
ability] and height, the likely influences of gene-environment correlations
and interactions on their developmental processes, and the potential for
genetic background and environmental circumstances to release previously
unexpressed genetic variation suggest that very different combinations of
genes may produce identical IQs or heights or levels of any other
psychological trait. And the same genes may produce very different IQs and
heights against different genetic backgrounds and in different environmental
circumstances. This would be especially the case if height and GCA and other
psychological traits are only single facets of multifaceted traits actually
under more systematic genetic regulation, such as overall body size and
balance between processing capacity and stimulus reactivity. Genetic
influences on individual differences in psychological characteristics are real
and important but are unlikely to be straightforward and deterministic. We
will understand them best through investigation of their manifestation in
biological and social developmental processes."

Chabris, C. F., Hebert, B. M., Benjamin, D. J., Beauchamp, J., Cesarini, D.,
van der Loos, M., ... & Laibson, D. (2012). Most reported genetic associations
with general intelligence are probably false positives. Psychological Science.

[http://coglab.wjh.harvard.edu/~cfc/Chabris2012a-FalsePositiv...](http://coglab.wjh.harvard.edu/~cfc/Chabris2012a-FalsePositivesGenesIQ.pdf)

"At the time most of the results we attempted to replicate were obtained,
candidate-gene studies of complex traits were commonplace in medical genetics
research. Such studies are now rarely published in leading journals. Our
results add IQ to the list of phenotypes that must be approached with great
caution when considering published molecular genetic associations. In our
view, excitement over the value of behavioral and molecular genetic studies in
the social sciences should be temperedءs it has been in the medical sciencesآy
a recognition that, for complex phenotypes, individual common genetic variants
of the sort assayed by SNP microarrays are likely to have very small effects.

"Associations of candidate genes with psychological traits and other traits
studied in the social sciences should be viewed as tentative until they have
been replicated in multiple large samples. Failing to exercise such caution
may hamper scientific progress by allowing for the proliferation of
potentially false results, which may then influence the research agendas of
scientists who do not realize that the associations they take as a starting
point for their efforts may not be real. And the dissemination of false
results to the public may lead to incorrect perceptions about the state of
knowledge in the field, especially knowledge concerning genetic variants that
have been described as 'genes for' traits on the basis of unintentionally
inflated estimates of effect size and statistical significance."

~~~
eblume
I used to work for a biotech company that shared a somewhat similar field to
23andme, although aimed at prenatal diagnostics. We were doing the exact thing
that #3 on their list claims. While I am not a scientist, my understanding is
that the 23andme has a reputation for being very sloppy at science. It's
perhaps useful as a source of personal information but I wouldn't trust
anything they talk about, as far as research goes.

Point in case, the whole 'noninvasive prenatal diagnostics' thing was
something we had down to a commercial clinical procedure... in 2011. In fact
we had it down pretty good in 2009 (before I was at the company), but it takes
a long time to get through certification with these sorts of tests. My
understanding is that research groups had been doing that sort of thing since
2004 - I don't know when the first human fetus was sequenced but it was
certainly not last October.

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pavs
Does anyone know of any 23andme like service in South East Asia?

When I was in NY, I sent my sample kit from NJ (They don't accept kits from
NY). But they never got, but it was too late for me to resend because I moved
out of USA. That was 3 years ago.

I have been looking for alternatives without any luck.

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untilHellbanned
#10 "Autism Study Reveals No Genetic Associations" is pretty interesting
though probably reflects heterogenous population more than no actual causal
mutations

