Natural Selection and Body Shape in Eurasia

Prior to the modern era of genomics, it was claimed (without good evidence) that divergences between isolated human populations were almost entirely due to founder effects or genetic drift, and not due to differential selection caused by disparate local conditions. There is strong evidence now against this claim. Many of the differences between modern populations …

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Genetic variation in Han Chinese population

Largest component of genetic variation is a N-S cline (phenotypic N-S gradient discussed here). Variance accounted for by second (E-W) PC vector is much smaller and the Han population is fairly homogeneous in genetic terms: …while we revealed East-to-West structure among the Han Chinese, the signal is relatively weak and very little structure is discernible …

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Scientific Consensus on Cognitive Ability?

From the web site of the International Society for Intelligence Research (ISIR): a summary of the recent debate involving Charles Murray, Sam Harris, Richard Nisbett, Eric Turkheimer, Paige Harden, Razib Khan, Bo and Ben Winegard, Brian Boutwell, Todd Shackelford, Richard Haier, and a cast of thousands! ISIR is the main scientific society for researchers of …

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CNGB: China National Gene Bank

Unbeknownst to me I’ve been skyping with a collaborator who has been working from this location. SCMP: China opens first national gene bank, aiming to house hundreds of millions of samples China’s first national gene bank, claimed to be the largest of its kind in the world, officially opened on Thursday to store and carry …

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If

Every day, we propagate the E. coli populations in the long-term evolution experiment (LTEE) by transferring 0.1 ml of the previous day’s culture into 9.9 ml of fresh medium. This 100-fold dilution and regrowth back to stationary phase—when the bacteria have exhausted the resources—allow log2 100 = 6.64 generations (doublings) per day. We round that …

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Everything is Heritable

  The figure above comes from the paper below. A quick glance shows that for pairs of individuals: 1. Increasing genetic similarity implies increasing trait similarity (for traits including height, cognitive ability, years of education) 2. Home environments (raised Together vs Apart; Adoptees) have limited impact on the trait (at least in relatively egalitarian Sweden). …

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The Gulf is Deep (Heinlein)

  The novella Gulf predates almost all of Heinlein’s novels. Online version. The book Friday (1982) is a loose sequel. Wikipedia: Gulf is a novella by Robert A. Heinlein, originally published as a serial in the November and December 1949 issues of Astounding Science Fiction and later collected in Assignment in Eternity. It concerns a secret society …

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Can Life emerge spontaneously?

It would be nice if we knew where we came from. Sure, Darwin’s insight that we are the product of an ongoing process that creates new and meaningful solutions to surviving in complex and unpredictable environments is great and all. But it requires three sine qua non ingredients: inheritance, variation, and differential selection. Three does …

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Genetics, Cognitive Ability, and Education (conversation with Cambridge PhD candidate Daphne Martschenko)

Genetics, Cognitive Ability, and Education (conversation with Cambridge PhD candidate Daphne Martschenko) Further conversation with Cambridge PhD candidate Daphne Martschenko concerning genetics of cognitive ability, implications for education policy, etc. See also earlier conversation: https://www.youtube.com/watch?v=YVqkvHpLfuQ Dunedin paper referenced in the video (polygenic score prediction of adult success for different SES groups): http://infoproc.blogspot.com/2016/09/genomic-prediction-of-adult-life.html Tweet

Machine Learning for Personalized Medicine: Heritability-based models for prediction of complex traits (David Balding)

Highly recommended talk by David Balding on modern approaches to heritability, relatedness, etc. in statistical genetics. (I listened at 1.5x normal speed, which worked for me.) MLPM (Machine Learning for Personalized Medicine) Summer School 2015 Monday 21st of September Heritability-based models for prediction of complex traits by David Balding Complex trait genetics has been revolutionised …

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Cultivated sweet potatoes contain Agrobacterium inserted T-DNA that is absent in wild sweet potato relatives. A natural GMO?

Genetic modification (GM) of food crops is a very hot topic in today’s society. When researchers discovered that certain bacteria had the ability to transfer their own DNA into plant genomes, the applications seemed endless. By taking advantage of this transfer DNA (T-DNA) mechanism, scientists can selectively transfer specific genes into the target plant to …

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This is for PZ Myers

Scott Alexander (Slate Star Codex), Garrett Jones (Hive Mind), and Razib Khan (GNXP) alerted me (via Twitter) of this post by PZ Myers. Myers is both confused and insulting in his blog post, but I’ll refrain from ad hominem attacks, and just focus on the science. Myers seems to think that humans with much better …

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Genetic ancestry and brain morphology

Population structure — i.e., distribution of gene variants by ancestral group — is reflected in brain morphology, as measured using MRI. Brain morphology measurements can be used to predict ancestry. Strictly speaking, the data only show correlation, not genetic causation, but the most plausible interpretation is that genetic differences are causing morphological differences. One could …

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Cognitive Genomics Interview

This is a discussion with Cambridge University PhD candidate Daphne Martschenko. Topics covered include: genetics of cognition, group differences, genetic engineering. The NYC roundtable on genius she mentions is here. Blog readers may also be interested in this event at the 92nd Street Y (Thu, Mar 10, 2016, 8:15 pm, Location: Lexington Avenue at 92nd …

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GCTA, Missing Heritability, and All That

Bioinformaticist E. Stovner asked about a recent PNAS paper which is critical of GCTA. My comments are below. It’s a shame that we don’t have a better online platform (e.g., like Quora or StackOverflow) for discussing scientific papers. This would allow the authors of a paper to communicate directly with interested readers, immediately after the paper …

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The view from here

A mind of von Neumann’s inexorable logic had to understand and accept much that most of us do not want to accept and do not even wish to understand. This fact colored many of von Neumann’s moral judgments. — Eugene Wigner, in John von Neumann (1903 – 1957), Year book of the American Philosophical Society …

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BBC interview with Robert Plomin

I recommend this BBC interview with Robert Plomin. Robert is a consummate gentleman and scholar, working in a field that inevitably attracts controversy. (Via Dominic Cummings.) Professor Robert Plomin talks to Jim Al-Khalili about what makes some people smarter than others and why he’s fed up with the genetics of intelligence being ignored. Born and …

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Meritocracy and DNA

Read Toby Young’s new article The Fall of the Meritocracy. The adoption of civil service and educational placement examinations in England and France in the 19th century was consciously based on the Chinese model (see Les Grandes Ecoles Chinoises). Although imperfect, exams work: we have no better system for filtering talent. But few are willing to acknowledge …

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Endings and beginnings

I returned from my first trip to China. Happily I was able to recover enough to get back into the field, but alas only once. We hiked to the border of Wolong Nature Reserve and the reserve to the north, Caopo. This area had excellent panda habitat and we found four different fecal samples. From …

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No genomic dark matter

Let me put it very simply: there is NO genomic “dark matter” or “missing heritability” — it’s merely a matter of sample size (statistical power) to identify the specific variants that account for the total expected heritability. The paper below (see also HaploSNPs and missing heritability) suggests that essentially all of the expected heritability can …

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One Hundred Years of Statistical Developments in Animal Breeding

This nice review gives a history of the last 100 years in statistical genetics as applied to animal breeding (via Andrew Gelman). One Hundred Years of Statistical Developments in Animal Breeding (Annu. Rev. Anim. Biosci. 2015. 3:19–56 DOI:10.1146/annurev-animal-022114-110733) Statistical methodology has played a key role in scientific animal breeding. Approximately one hundred years of statistical …

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Fifty years of twin studies

The most interesting aspect of these results is that for many traits there is no detectable non-additivity. That is, gene-gene interactions seem to be insignificant, and a simple linear genetic architecture is consistent with the results. Meta-analysis of the heritability of human traits based on fifty years of twin studies Nature Genetics (2015) doi:10.1038/ng.3285 Despite …

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Après nous le déluge

You can always blame the Chinese. See also A prudent path forward for genomic engineering and germline gene modification (Baltimore et al.) and Germ line editing and human evolution. Science: Embryo engineering alarm … In 1975, the Asilomar conference center hosted a meeting where molecular biologists, physicians, and lawyers crafted guidelines for research that altered …

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The Fourth Law of Behavior Genetics?

I believe the law stated below almost follows from the observation that humans brains are complex machines: hence the DNA blueprint has many components, and variance is spread over these components  :^) However, note the evidence for discrete genetic modules of large effect in other species: Discrete genetic modules can control complex behavior (burrowing behavior in …

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