Category: Genomics

  • Natural selection and dopamine receptor genes

    Long time readers will be familiar with the large literature in behavior genetics/genomics and dopamine receptor genes. So with that, I point you to a paper exploring the patterns of variation and their relationship to possible natural selection, No Evidence for Strong Recent Positive Selection Favoring the 7 Repeat Allele of VNTR in the DRD4…

  • Not just genomics: the creeping future

    In 2007 Reihan Salam asked me when the $1,000 genome was going arrive. On paper, probably around this year, or early next. But as I’ve been suggesting it really isn’t that big of a deal (the sticker price isn’t real in any case, someone will want the publicity). Over at The Crux I try and…

  • Tigons, ligers, leguars, and jagupards, oh my!

    The recent publicity around the gorilla genome highlighted to me that eastern and western gorilla lineages seem to have diverged ~1 million years ago. In the process of trying to figure out hybridity I stumbled upon this matrix from Wikipedia on panthera hybrids: Lion ♀ Tiger ♀ Jaguar ♀ Leopard ♀ Lion  Lion Liger Liguar Lipard Tiger  Tigon Tiger…

  • Beyond trees and European trees

    Submitted for your approval, a very important post and preprint from Dr. Joseph Pickrell, Identifying targets of natural selection in human and dog evolution. If you read the preprint there’s a lot of good stuff. Dienekes highlighted the most relevant aspect: representation of genetic relationships with phylogenetic trees mask the likely reality of gene flow…

  • The data sets in the dark

    Recently I was tipped off to the appearance of a new paper, Genome-Wide Association Study Identifies Chromosome 10q24.32 Variants Associated with Arsenic Metabolism and Toxicity Phenotypes in Bangladesh. This is the section which caught my eye: “Using data on urinary arsenic metabolite concentrations and approximately 300,000 genome-wide single nucleotide polymorphisms (SNPs) for 1,313 arsenic-exposed Bangladeshi…

  • Adam’s end was never in the cards

    There has been a lot of talk in the media about a new paper which reports that the Y chromosome is not deteriorating, as had been previously inferred from the data. In the 2004 Bryan Sykes wrote Adam’s Curse: A Future Without Men which used this model as a framing device (and naturally elicited great general…

  • The race question: are bonobos human?

    Recently Jason Antrosio began a dialogue with readers of this weblog on the “race question.” More specifically, he asked that we peruse a 2009 review of the race question in the American Journal of Physical Anthropology. Additionally, he also pointed me to another 2009 paper in Genome Research, Non-Darwinian estimation: My ancestors, my genes’ ancestors.…

  • Loss-of-function & variation in load

    Greg Cochran pointed out something that I’d been considering about the MacArthur et al. paper: if the average human (OK, non-African human) has ~100 loss-of-function variants, then the standard deviation should be ~10. That’s because the distribution is presumably poisson, and variance = mean, and the square root of the of the variance (~100) is the…

  • Socialized personal genomics?

    Norway to bring cancer-gene tests to the clinic: Norway is set to become the first country to incorporate genome sequencing into its national health-care system. The Scandinavian nation, which has a population of 4.8 million, will use ‘next-generation’ DNA sequencers to trawl for mutations in tumours that might reveal which cancer treatments would be most…

  • ChromoPainter & fineSTRUCTURE on a South Asian data set

    Over at Harappa DNA Zack ran ChromoPainter/fineStructure on his South Asian data set and posted the results. The new method immediately makes a few things clear: 1) The “South Asians” in the HGDP data set that’s been used for so long are rather on the inbred side, and relatively genetically distinct as far as South Asian populations…

  • Out of who knows where

    In The New York Times, DNA Turning Human Story Into a Tell-All: The tip of a girl’s 40,000-year-old pinky finger found in a cold Siberian cave, paired with faster and cheaper genetic sequencing technology, is helping scientists draw a surprisingly complex new picture of human origins. The new view is fast supplanting the traditional idea…

  • Socialized medicine + personal genomics = ?

    My own working assumption is that the demand side impulse toward mass adoption of human genomic technology in the USA is going to be dampened by fear of downside consequences, GINA notwithstanding. Rather, I assume that the more deregulated consumer environment in parts of Asia with very low fertility rates, as well as European states…

  • Population structure using haplotype data

    The Pith: New software which gives you a more fine-grained understanding of relationships between populations and individuals. According to the reader survey >50 percent of you don’t know how to interpret PCA or model-based (e.g., ADMIXTURE) genetic plots, so I am a little hesitant to point to this new paper in PLoS Genetics, Inference of…

  • When Eve met Creb

    The excellent site io9 has a piece up today which is a fascinating indicator of the nature of popular science publications as a lagging indicator. It is a re-post of a piece published last April, How Mitochondrial Eve connected all humanity and rewrote human evolution. In it you have an encapsulation of a particular period…

  • Personal genomics and adoption

    With DNA Testing, Suddenly They Are Family: Several companies provide tests that can confirm whether adoptees are related to individuals they already know. Others cast a wider net by plugging DNA results into databases that contain tens of thousands of genetic samples, provided mostly by people searching for their ancestral roots. The tests detect genetic…

  • Genetic profiling: CSI edition

    Apparently the national media is reporting that scientific genealogy may result in leads to a cold case. The principle is simple: apparently Y chromosomal material was matched to public genealogy databases. From this the researcher concluded that the perpetrator is probably a male line descendant of Robert Fuller of Salem, Massachusetts. Contrary to the urban…

  • How the Amhara breathe differently

    I have blogged about the genetics of altitude adaptation before. There seem to be three populations in the world which have been subject to very strong natural selection, resulting in physiological differences, in response to the human tendency toward hypoxia. Two of them are relatively well known, the Tibetans and the indigenous people of the…

  • The quest for an Afrikaner genotype

    Update: If interested, please email me at contactgnxp -at- gmail -dot- com. Also, I am getting some feedback via 23andMe that people with white South African matches noticed Africa segments in many of the ancestry paintings. This has definitely increased by probability that the admixture proportion is ~5 percent. There will probably be a few…

  • Genes and Rex Wandalorum et Alanorum

    The idea of a “folk wandering” was once a well accepted idea in history, in particular for the phase of the Late Roman Empire, and the subsequent fall of the Western Empire. It’s a rather simple concept: the collapse of the Pax Romana occurred simultaneous with a mass ethnic reordering of Europe, primarily via the…

  • Mendelism is not magic

    Michelle points me to this article in The Lost Angeles Times, The Colors of the Family: I was holding my 1-year-old, ambling about downtown with some friends. White friends. She must have thought my boy belonged to one of them. There’s a simple explanation: I’m black but my son, Ashe, is white. At least he…

Razib Khan