genetics
clock | October 15, 2006Mendel's Garden #8: Harvest Edition is up on Discoverying Biology in a Digital World.
razib | October 12, 2006DNA trail points to human brain evolution:
A new study comparing the genomes of humans, chimps, monkeys and mice found an unexpectedly high degree of genetic difference in the human DNA regions that influence nerve cell adhesion, compared with the DNA of the other animals.
Accelerated evolution here allowed human brain cell connections to form with greater complexity, enabling us to grow bigger brains, the researchers suggest.
From the interview with Bruce Lahn:
2. Your work on genes involved in human brain evolution (i.e. ASPM and microcephalin) has focused on amino acid changes. It has been…
evolgen | October 12, 2006One of the greatest developments of the post-genomic era has been the refinement of the concept of the 'gene'. The central dogma states that genes encode RNA transcripts which are translated into the amino acid sequence that makes up a protein. But protein coding genes make up a small fraction of many genomes, so what does the rest of the genome do? Some say it's junk. Others say that it's involved in regulating the transcription of the other regions. And even others say that it's transcribed, but not translated. (Note: most think it's some combination of the three.)
We're now discovering…
razib | October 11, 2006The Dark Side of DNA is a review of Genes in Conflict, Austin Burt and Robert Triver's magisterial survey of the extant literature of 'selfish genetic elements.' Do you know what the killer 't-haplotype' is? You should, it is pretty bizarre.
evolgen | October 11, 2006
Sandy at Discovering Biology in a Digital World will be hosting the upcoming edition of Mendel's Garden. If you have written something about genetics, consider submitting it to this blog carnival. You can email Sandy or use the blog carnival submission page. The deadline for submission is Saturday afternoon (she may even let you wait until Sunday).
razib | October 10, 2006Check, 10 questions for Bruce "Gene Thug" Lahn. Check this player's ambitions out:
10. Looking back, would you make any changes in your educational path? If so, what?
Looking back, I might have chosen economics instead of biology, as it might have allowed my work to have a broader impact. But it's a tossup, and my feeling may well have stemmed from my constant impatience with lack of progress in my own work and therefore the perception that grass is greener on the other guy's pasture
Get it? The key is to crank up the body count!
razib | October 6, 2006Aside from the fact that they remind those of us who were exposed to Japanese movies of ninjas, why are veiled women so disconcerting? I bring this up because Jack Straw over in England is causing a controversy by talking about the fact that when he meets female constituents who are veiled he asks them to remove it. Of course some Muslims are saying that their religion demands a veil, which is utter bullshit, their interpretation of their religion demands it. I know from personal experience that even many Muslims find the veil disturbing and are uncomfortable with it. Occasionally people…
razib | October 5, 2006JP offers us some links about brain development & genetics. He also reports on a preprint which implies selection for musculature in Africans. Finally, David discusses R.A. Fisher addressing the contentious issue of race.
evolgen | October 5, 2006Nick Wade thinks there's a race to decode genomes. CNN thinks there's a race to map the human genome:
$10 million prize for mapping human genomes
Sturtevant mapped genomes. The contest is to sequence and assemble a genome. Well, that's what we think the contest is. And it's pretty unclear how they will measure accuracy.
pharyngula | October 5, 2006You may have heard about that odd hothead mutation in Arabidopsis that seemed to be violating a few principles of basic genetics—there was an unexpectedly high frequency of revertants that suggested there might be a reservoir of conserved genetic information outside the genome. Reed Cartwright proposed an alternative explanation, that gamete selection could skew the results. Now the latest reports suggest that the bias was an artifact of foreign pollenization (which I think is interesting in itself. Life is damned good at sneaking its genes in wherever it can.)
Anyway, if that's all…
clock | October 4, 2006In the light of this years' Nobel Prizes in Physiology and Chemistry (all RNA all the time), it would be interesting to think how would transcription, translation, gene regulation and replication work if DNA has evolved to be like this!?
clock | October 4, 2006For easy-to-understand quick look at the evolution of vision I have to refer you to these two posts by PZ Myers, this post of mine, and these two posts by Carl Zimmer.
Now, armed with all that knowledge, you will curely appreciate the importance of this new study:
Compound Eyes, Evolutionary Ties:
Biologists at the University of California, San Diego have discovered that the presence of a key protein in the compound eyes of the fruit fly (which glow at center due to a fluorescent protein) allows the formation of distinct light gathering units in each of its 800 unit eyes, an evolutionary…
clock | October 3, 2006As you have probably heard already, Andrew Fire and Craig Mello have won the Nobel Prize in Medicine for the discovery of RNA interference.
Jake Young explains what RNAi are and what they do and why is this so revolutionary. Then he explains why those two people got the Nobel for this work instead of some others.
Alex Palazzo (also here), Abel PharmBoy, Carl Zimmer, Nick Anthis and PZ Myers have more and explain it much better than I could ever do. The last time the Nobel was given for work I really understand and like was in 1973 - ah, the good old days when the Nobel did not require…
razib | October 2, 2006JP at my other blog has two posts on molecular evolution worth checking out (the second post was inspired by a comment from RPM).
razib | October 2, 2006The Howard Hughes Medical Institute has a press release out about a new paper, Transforming the architecture of compound eyes, in Nature. The last sentence of the abstract states:
Our results provide a molecular atlas for the construction of microvillar assemblies and illustrate the critical effect of differences in a single structural protein in morphogenesis.
The press release isn't as pithy:
Zuker said the findings offer an important lesson about the beauty of evolution. "It's not unusual to see alterations in regulatory proteins with a profound effect on form and function," he said. "…
razib | October 1, 2006This is a shout out to the biologists out there: do you think the concept of dominance and recessive is worthwhile? In other words, does it help in conceptualization more than it hurts? Clearly the idea of recessiveness of deleterious traits helps in comprehending why such alleles exist in the ambient genetic background of a population and can reemerge via inbreeding.1 On the other hand, my own experience is that if you try to move the conversation to additive polygenic traits, which I think are interesting and need to be understood to really "get" population genetics you have to keep…
razib | October 1, 2006Time has a long piece about the sequencing and comparative genetics between humans and the great apes. There is also some material thrown in about Neandertals.
razib | September 30, 2006RPM has a post up about Y and mtDNA lineages, and what they can (or can't) tell us about demographic history. I'm pretty skeptical myself about the broad and detailed deep time inferences some make with these markers (see The Real Eve for an extreme case), but Dienekes points me to a situation where there is some utility to this methodology:
The differential relative contribution of males and females from Africa and Europe to individual African American genomes is relevant to mapping genes utilizing admixture analysis...The European genetic contributions were highest (and African lowest)…
razib | September 30, 2006One of the major dialogues in evolutionary genetics in the 20th century was that between R.A. Fisher and Sewall Wright. It is so seminal that the term Fisher-Wright controversy is often used. One of the major points of disagreemant between Fisher and Wright was the role of population substructure and the relevance of long term effective population size in shaping the trajectory of allele frequencies over time. At my other blog David B is starting a series which addresses this issue. The initial post deals with the period before the publication of The Genetical Theory of Natural Selection.