genetics
razib | March 25, 2007Paul Zed Myers comments on Alan MacNeill's contention:
To an evolutionary biologist, such pan-specificity combined with continuous variation strongly suggests that one is dealing with an evolutionary adaptation.
Myers sayeth:
For another example, people in the US largely speak English, with a subset that speak Spanish, and a few other languages represented in scattered groups. That does not mean we should talk about English as an adaptive product of evolution. Language, definitely - there's clearly a heritable biological element to that ability. Similarly, religion may easily be a consequence…
razib | March 25, 2007Over at GNXP Classic David B has an introductory preface to a series of posts he plans to write on the great evolutionary geneticist Sewall Wright. David sums up:
As for my own assessment, for what little it is worth, in reading Wright I have realised that his achievement was truly massive. At the same time, I find it difficult to work up any great enthusiasm for his writings. This is partly due to the obscurities I have already mentioned, but also to a certain dryness and narrowness of scope. Whereas one can still read Fisher and Haldane and hope to find new insights and speculations, there…
razib | March 23, 2007One issue that has cropped up in the comments a few times here is a conflation between quantitative & population genetics. Though people seem to think they're interchangeable terms, they're distinct fields. That's why population genetics text books have chapters devoted specifically to quantitative genetics, and showing how the latter can be bridged with the former.
Roughly, population genetics is a "bottom up" field which deals with the dynamics of allele frequencies under the influence of evolutionary forces such as mutation, drift, selection and migration. In some ways it can be…
pharyngula | March 21, 2007Here's a clever (I think) observation in the efforts to eradicate malaria: the mosquitos that transmit malaria are also infected with the disease-causing parasite, so maybe if we cure malaria in mosquitos, it will end one intermediate step in the transmission chain. It sounds like a crazy idea, but recent experiments suggest that it might just work. It's got the advantage of allowing the use of transgenic techniques on the mosquito population, where you don't have to worry about patient's rights or whether a few of your experimental subjects will die during the procedure, and you can just let…
razib | March 21, 2007I figured I would just note this, another skin color study:
...We previously reported significant associations of two coding region polymorphisms with hair, skin, and eye color in Caucasians. Here we characterize the promoter region of MATP [SLC45A2] identifying two new transcription start sites and a novel duplication...A total of 700 individuals from five different population groups (529 Caucasians, 38 Asians, 46 African Americans, 47 Australian Aborigines, and 40 Spanish Basques) were genotyped for known promoter polymorphisms...Allele frequencies of all three polymorphisms were…
grrlscientist | March 20, 2007
A transgenic mosquito carrying a gene that confers resistance to the malaria parasite. These mosquitoes had another gene inserted into them to make their eyes fluoresce, to distinguish them from unmodified insects. (Image: PNAS)
A genetically modified (GM) strain of malaria-resistant mosquito has been created that is better able to survive than disease-carrying insects.
The transgenic insect strain carries a gene that prevents infection by the malaria parasite. This provides new hope for one malaria control strategy where the transgenic insects are released into the wild and they then take…
clock | March 16, 2007About a year ago, there was a great paper about polyphenism in moth caterpillars.
Now, in the new issue of Seed Magazine, PZ Myers uses that example to teach you all about it. Cool reading on one of my favourite topics (outside clocks, of course).
razib | March 16, 2007Dienekes has a nice post up on the follies and failures of historical population genetics. As he notes, part of the problem is that people really want to find x instead of !x, and with a statistical science that is really, really, bad.
evolgen | March 15, 2007I'm really digging the interviews with high profile scientists that Current Biology has been publishing. Last November I quoted their interview with Michael Ashburner (ie, he who will not pose with Prof. Steve Steve) on his thoughts on open access publishing and pointed out that they were being published in a non-open access journal. In the most recent issue, they interview Stephen O'Brien, head of the Laboratory of Genomic Diversity at the National Cancer Institute. O'Brien was trained as a Drosophila geneticist, and now works on topics as diverse as cheetah population genetics and HIV…
razib | March 14, 2007Over at GNXP Classic Ikwa points to some papers from the PLOS One project, which facilitates public feedback in the peer review process. Ikwa has a full list of papers, but I'll list the ones that he highlighted as of particular interest:
Melanesian mtDNA Complexity
Meta-Analysis in Genome-Wide Association Datasets: Strategies and Application in Parkinson Disease
Expression Signature Predicts Human Breast Cancer Prognosis
Catechol-O-Methyltransferase Gene Polymorphism Modifies the Effect of Coffee Intake on Incidence of Acute Coronary Events
Transcriptional Changes Common to Human Cocaine,…
razib | March 14, 2007From PLOS Genetics Identification of the Imprinted KLF14 Transcription Factor Undergoing Human-Specific Accelerated Evolution:
Imprinted genes are expressed in a parent-of-origin manner and are located in clusters throughout the genome...By sequence analysis of numerous species, we place the timing of this event after the divergence of Marsupialia, yet prior to the divergence of the Xenarthra superclade. We identify a large number of sequence variants in KLF14 and, using several measures of diversity, we determine that there is greater variability in the human-lineage with a significantly…
clock | March 14, 2007Today is a big day on Plos-Biology for the Oceanic Microbial Diversity Genomics. Last night they published not one, not two, but three big papers chockfull of data.
Accompani\ying them are not one, not two, not three, not even four, but five editorial articles about different aspects of this work.
James has already homed in on one important part of the discovery: the preponderance and diversity of proteorhodopsins - microbial photopigments that are capable of capturing solar energy in a manner different from photosynthesis. As always, light-sensitive molecules are thought to be tightly…
razib | March 13, 2007A few weeks ago I purchased what I have since referred to as a "coffee table book for nerds," Martin Novak's Evolutionary Dynamics: Exploring the Equations of Life, a richly illustrated hardcover which is eminently browsable. In keeping with the focus of Nowak's own researches the chapters in this work are heavy on game theory, and light on population & quantitative genetics. This is fine by me, I'm interested in boning up on game theory beyond hawk & dove ESSes. But there is some evolutionary genetic material, though offering his more cutting edge spin.
In the second chapter there…
evolgen | March 13, 2007This post is part of a series documenting Professor Steve Steve's recent visit to Philadelphia for the Drosophila Research Conference (aka, the Fly Meeting).
After tracking down Steve Steve in the lobby of the hotel on Saturday, we picked up some food at the Reading Terminal Market -- a permanent sort-of-farmers-market next to the Philly Convention Center. The place was pretty packed, due in part to the Flower Show going on next door. Steve Steve was a little bummed that he didn't have time to check out any of the garden displays -- being an amateur horticulturalist and developer of the…
evolgen | March 12, 2007
What a weekend! Professor Steve Steve and I returned from Philadelphia on Sunday after hanging out with the Drosophilists. Steve arrived in Philly on Thursday morning on a direct flight from Iowa City, but the staff at the Philadelphia Marriott couldn't understand his thick accent when he asked that they notify me of his arrival. The little guy wandered the lobby of the hotel until Saturday morning, when I found him nibbling on the flamboyant floral display. That wasn't the only thing the Marriott screwed up.
More stories and pictures can be found below the fold.
Why the Marriott sucks:…
razib | March 6, 2007Nick Wade has a new article which draws upon the two new books about the genetics of the British Isles, Saxons, Vikings, and Celts, by Bryan Sykes, and The Origin of the British, by Stephen Oppenheimer. The gist is that the British peoples are genetically very similar, and predominantly the descendents of post-Ice Age settlers who swept up along the Atlantic seaboard from the "Iberian refugia".1 To a first approximation this story is about right, the various studies seem to be converging upon the finding that most Britons and Irish are closer to each other than they are to continental…
razib | March 6, 2007The current Mendel's Garden just went up over at "sperm competition" Matt's place.
razib | March 5, 2007I have often said that I tend to see "group selection" as a lesser evolutionary force when set against lower levels of evolutionary processes, e.g., "individual" or "gene" level selection. By group selection I do not mean pro-social tendencies, or the success of individuals who band together as a group, but rather evolutionary processes which can not be reduced down to a lower level of selection. In other words, evolution is acting directly upon the group as an emergent property of a collection of individuals. My skepticism toward groups selection is conventional and orthodox: evolutionary…
razib | March 1, 2007Thought I'd post this link to a conference on the biology and genetics of music. As someone who is tone deaf I'm interested in the topic, though obviously as an outsider.
razib | February 27, 2007Early man 'couldn't stomach milk'
Working with scientists from Mainz University in Germany, the UCL team looked for the gene that produces the lactase enzyme in Neolithic skeletons dating between 5480BC and 5000BC.
These are believed to be from some of the earliest farming communities in Europe.
The lactase gene was absent from the DNA extracted from these skeletons, suggesting that these early Europeans would not be tolerant to milk.
The paper will be Absence of the Lactase-Persistence associated allele in early Neolithic Europeans in PNAS. First LCT, then OCA2, and god knows what else?…