Over at my other blog I have a post up about inbreeding fundamentalist Mormons. When brown Muslims are hittin’ it with near relations that warrants eyes averted, but if I point to slack-jawed Anglos, well, that is BoingBoing worthy. But in any case, my post focused on an older article about the prevelance of fumerase deficiency among many children within the fundamentalist Mormon community of Colorado city. But one thing struck me about the article, the top-down pro-natalist and conformist nature of the community seemed to be a perfect example of the functionalist notions of evolutionary biologists like David Sloan Wilson. He promoted the reemergence of functionalism and evolutionary analogies in sociology and anthropology in , the hyper-fecund & genetically inbred fundamentalist Mormons are an ideal case of a group level super-organism, but just like a putative lineage of human clones who reproduce parthenogenetically they are clearly doomed. I suspect that functionalism isn’t totally bunk, but like socialism it looks better on paper than it is in practice, really successful long term societies are more decentralized, flexible and fluid.
Month: August 2006
Human Lineage-Specific Amplification, Selection, and Neuronal Expression of DUF1220 Domains
Human Lineage-Specific Amplification, Selection, and Neuronal Expression of DUF1220 Domains:
…A genome-wide survey of gene copy number variation among human and great ape lineages revealed that the most striking human lineage-specific amplification was due to an unknown gene, MGC8902, which is predicted to encode multiple copies of a protein domain of unknown function (DUF1220). Sequences encoding these domains…show signs of positive selection, and are increasingly amplified generally as a function of a species’ evolutionary proximity to humans…DUF1220 domains are highly expressed in brain regions associated with higher cognitive function….
From the conclusion:
The genomic regions that harbor DUF1220 sequences appear to be particularly complex and, as a result, different genome assemblies differ with respect to the predicted number of DUF1220-encoded sequences. However, two recent genome-wide BAC aCGH cross-species studies…independently support the findings reported here that DUF1220-encoding genes show human lineage-specific increases in copy number and appeared with remarkable rapidity. If they indeed are the result of strong positive selection, they may play an important role in human lineageâ€“specific traits….
John Hawks has more.
98% sequence identity with a chimp? Yeah, but we’re all human where it counts baby (no mention of sperm or testes in the paper). Figure below the fold.
Against The Politically Incorrect Guide to Darwinism and Intelligent Design
As someone who makes no bones about being against politically correct evolutionary biology, I will take up RPM’s call to link to Panda’s Thumb’s chapter-by-chapter rebuttal of The Politically Incorrect Guide to Darwinism and Intelligent Design. They fight Creationism so I don’t have too!
Gene therapy starting to get useful?
Some encouraging gene therapy news in Science:
Cancer Regression in Patients After Transfer of Genetically Engineered Lymphocytes
Using a retrovirus encoding a T cell receptor, we report here the ability to specifically confer tumor recognition by autologous lymphocytes from peripheral blood. Adoptive transfer of these transduced cells in fifteen patients resulted in durable engraftment at levels exceeding ten percent of peripheral blood lymphocytes for at least two months post infusion. We observed high sustained levels of circulating, engineered cells at one year post-infusion in two patients, that both demonstrated objective regression of metastatic melanoma lesions. This study suggests the therapeutic potential of genetically engineered cells for the biologic therapy of cancer.
According to reports in Swedish media (i.e. Dagens Nyheter) two late-stage terminal patients out of 17 trial subjects were cancer free after 18 months.
Selection for adaptation
Human bodies maintain an optimal environment for cellular function. Cold-blooded animals function sluggishly when cold. I’ve wondered how bacteria manage to function at different temperatures. I’d assumed that bacteria are highly adapted to either high or low temperatures and that homeostatic feedback maintains biological systems in a viable range over modest daily temperature changes. But what happens when their environment rapidly changes? Does that bacterial line die out? Perhaps not.
“A general rule for enzyme reactions states that as the heat rises, so does the reaction rate. Contrary to this rule, and the scientist’s expectations, both reaction rates peaked at a certain point, and remained steady thereafter. For each enzyme, the peak occurred in the bacteria’s ‘comfort zone.’ Further comparisons of the enzymes, which were nearly identical, turned up differences in just two of the hundreds of amino acids making up the enzyme sequence. When the scientists replaced these two amino acids in the enzyme adapted to the moderate temperatures with those of the heat-loving enzyme, they observed an increase of about 10 degrees in the average temperature at which the reaction rate peaked. Scherz: ‘This study shows that enzyme efficiency is tuned to the average temperature of the bacterial habitat, rather than the immediate conditions. This may protect the cells from harmful swings in enzyme activity’ “
In this experiment, changing two amino acids in an enzyme changed the temperature of peak reaction rate. The bacteria colony could adapt to new temperatures with just a few mutations. Life has evolved to adapt rapidly to changing environments. Lifeforms that couldn’t adapt went extinct.
Inbreeding among Mormons
A reader pointed me to this fascinating, if tragic, article about the rise of rare recessive diseases among a schismatic Mormon sect which dominates Colorado City. This group has been in the news since the their “prophet” was just arrested. The article points out that because of the inbred nature of the community, and its small size, one particular rare disease, Fumerase Deficiency, has now become rather common. I have talked about inbreeding before. Most of us know the problems that crop up intuitively from experience, rare traits begin to spread in an inbred population. But, what needs to be emphasized is the greater problem from long term customary inbreeding, as is common in much of the Muslim world (and now in the Muslim Diaspora in the West), and in isolated cases as above.
Biology’s future as a science
Lubos Motl asked me to comment on this majestic post by a computational biologist at Stanford. This paragraph is worth quoting:
I will enumerate three main points, all of which represent both a challenge and an opportunity. The first will deal with a scientific challenge of a theoretical orientation, namely the lack of a theory for biology. The second with the sociological organization of biologists and biology departments at the leading research institutions. And the third will be part science, part sociology, having to do with the focus of current experimental methods and programs on biomedical research as opposed to basic biological research. The challenges are listed according to my own judgment of their importance.
Here it is an important quote from my exchange with theoretical evolutionary biologist David Haig in regards to theory & biology:
Question: Do you believe most biologists, even evolutionary biologists, appreciate formal theory?
Answer: Most biologists do not appreciate formal theory. Theory is more respected by evolutionary biologists as a group.
Off with her head!
Robert Wright, unreflective stereotype
A few weeks ago I watched the Robert Wright Ann Althouse diavlog. One thing that struck me was that in the beginning they addressed Althouse’s political ideology (i.e., was she a libertarian?). Althouse offered that she considered herself an independent, who voted for Feingold and Bush in 2004, splitting her ticket. Up until that time she has uniformly voted Democrat. She observed that her own experience is that when she did not toe the right-wing line she was ignored, but when she agreed with the Right they praised her. In contrast, the Left ignored her because of their disagreemants on several issues. The general opinion was that the Left shunned heretics and the Right sought converts. Interestingly, Wright spent the rest of the diavlog being surprised when Althouse expressed liberal views on particular topics, and even hopefully mooted the possibility that she could “come back” to “their side.” This, throughout an interview where she had expressed a host of different views, some on Wright’s “side,” and also offered that historically she tended to vote Democrat. Watch the whole thing, and this is not meant as a criticism (I don’t really create except as a data point in favor of what Althouse has referred to), but Wright seemed to exemplify exactly the tribalist purity which Althouse claimed was a problem on the Left, ignoring their commonality.
Anyway, I don’t comment much on politics on this blog because I have nothing to say, but I was pretty shocked that Wright behaved in such a manner even after addressing this tendency with Althouse.
Reducing fat fitness
In the wake of the British National Health Service denying IVF treatments to very obese women Big Fat Blog says:
This recommendation is discrimination, pure and simple. What the hell, really? Fat people are told they can’t adopt and told they can’t get pregnant (from both societal and medical angles); let’s just add in some more. For people who want to get pregnant, this is a slap in the face. And it speaks a little more to social engineering, methinks – don’t even allow fat people to breed, because, well, their kids might be fat. And you know what that means.