Deep inside an underground compound within the evil lair of the American Anthropological Association, Lord Skeletor summoned a scientist to spread falsehoods about the science of monoamine oxidase A, the warrior gene. That scientist was Christopher Irwin Smith, Associate Professor of Biology at Willamette University. Dr. Smith set about penning a diatribe full of errors and misleading innuendo. “I shall post this on the Internet and not allow better-informed people to comment on it,” he muttered before mustering an evil cackle that echoed through his dark private chamber.
Our investigators have uncovered the following especially telling response comment:
Dr. Smith,
Your impressive background prevents me from having any sympathy for you regarding the multiple egregious errors in this post. Probably the worst aspect of it is the timing because the last two years have produced two important meta-analyses confirming MAOA as an aggression and antisocial behavior gene. I’m guessing you have no awareness of either one.
“…Nielsen and Williamson’s studies were able to identify many regions in the genome that appear to have experienced recent natural selection, but MAO-A is not one of them.”
You neglected to mention that their study examined single-nucleotide polymorphisms, not repeat polymorphisms, like either of the functional MAOA-uVNTR promoters. The same is true for Voight et al.
“it is likely that these genetic variants are not –on their own– associated with violent or impulsive behavior… Simply carrying the ‘low expression’ allele in the MAO-A promoter does not have any effect at all on impulsivity or aggression.”
I doubt that you would have written this if you had been aware of the new meta-analysis by Ficks and Waldman, which came to the opposite conclusion.
“Instead, genetic variation in the MAO-A promoter seems to make some children less able to recover from abuse and childhood trauma, and therefore more likely to act out later in life (Caspi et al. 2002; Widom & Brzustowicz 2006).”
You are misrepresenting the findings of Caspi et al. It is MAOA-4R, not MAOA-3R that has the effect, which is a protective effect. According to Caspi et al, abuse could not affect those with MAOA-4R at all. Other studies have found the same protective effect against high testosterone levels and low IQ. Byrd and Manuck recently provided a meta-analysis verifying the abuse-MAOA interaction effect.
“Indeed, genetic variants associated with lower resilience to trauma are most common in Asian populations, not African ones (Sabol et al. 1998).”
Are you seriously saying that 61.0% is significantly higher than 59.1%? I think you must have been thinking about the copy-and-paste error by Lea and Chambers that claimed that 77% of Chinese men have MAOA-3R. I have labeled that the “idiot test” because it has caught many highly credentialed idiots who were trying to do the same thing that you are trying to do now: brush off decades of good research on MAOA. Ficks and Waldman only found a modest main effect of MAOA-3R, so you would need to argue not only that the gene is as common in Asians but also that the interacting factors (child abuse, high testosterone, an IQ less than 85) are as common in Asians, as well. Then, there is the issue of MAOA-2R….
“Note that Sabol study did not consider differences between populations in the frequencies of the ‘2-repeat’ alleles that Wade references…”
Did not consider? Gee, that is an interesting way of putting it. Of course, they tried to determine the allele frequency of each kind of allele in that VNTR, and they reported absolutely no instances of MAOA-2R in any group out of a total sample of over 2,000 X-chromosomes. MAOA-2R had not been discovered until the next year by Kunugi et al. Ever since, we have known that MAOA-2R is rare in whites but not that rare. Something is seriously wrong with the Sabol et al allele frequencies.
“To my knowledge, the frequency of the 2-repeat allele across populations has not been extensively measured; studies that have looked at its incidence appear to have focused on specific cohorts in the US as part of epidemiological studies.”
Is this your way of trying to cast doubt upon the allele frequencies reported in the literature for MAOA-2R in African-American men? Establishing an allele frequency does not require a 31-study meta-analysis. We have consistent findings from multiple studies that MAOA-2R is many times more common in African-American men than either white or Asian men. Would you like to read each study?
6 comments:
You are real good at thinking and analyzing but your Photoshoping needs work.
There is some comment on Amazon regarding MAO-A with B Foley from USC. May be of interest?
http://www.amazon.com/review/R1JQHV5W2ZS613/ref=cm_cr_rev_detmd_pl?ie=UTF8&asin=1594204462&cdForum=FxSY4R62Z9HHB2&cdMsgID=Mx2KS39SGTOOMFH&cdMsgNo=29&cdPage=3&cdSort=oldest&cdThread=Tx2VWBKC3CAWHOR&store=books#Mx2KS39SGTOOMFH
Foley is confused about many issues.
"there were only 8 positive cases out of the thousands in the study"
The study had 10 black men with MAOA-2R out of 174. Two had incomplete phenotype data. The "thousands" refers to people without DNA samples taken. I have pointed out these small numbers myself repeatedly, which calls for more research on MAOA-2R in Africa, where it will probably have an allele frequency much greater than 5-6%. (A newer study found an African-American male allele frequency for MAOA-2R of exactly 6%.) Although the effect did appear very strong in even that small number, our understanding of MAOA is much broader with a series of meta-analyses on other alleles of the gene made up of many tens of thousands of study subjects.
"even at high frequencies is at less than 5%"
Neither I nor Wade ever said that all black people are impulsively violent. Violent people are a small but highly consequential component of any society.
"Wade infers genome-wide patterns of selection from population differences in a single allele... invented scenario of heightened selection"
It is not necessary to prove natural selection had any role to prove that the different allele frequencies are consequential. In any case, the study of natural selection and MAOA refers to an entirely different set of alleles of MAOA, not MAOA-2R.
Also, most black people have MAOA-3R, which has a slight aggression effect but a large interaction effect. It can interact with having an IQ below 85, according to Fergusson et al, which is found in about half of African Americans.
The comments by B. Foley that were referenced by 'Anonymous' above are comments in a thread to my review in Amazon to Wade's book.
Responding to commenters on Amazon has become a new part time job for me. For the last week I have been waking up each morning and going to the computer to prepare my responses. There is plenty of work.
I gave the book a good review but I had some disagreements with it. The anti-Wade people are made of sterner stuff. They will abide no compromise. Wade must be destroyed!!
The link to Dr. Smith's diatribe is an example. Wade speaks of the three primary races which sets up Smith for a tendentious discussion of factor analysis software. In the immortal words of Hillary - "What difference does it make?" Wade says three major races and a number of minor races. Surely that's a mainstream position.
Then he accuses Wade of confusing modern race classifications aided by statistical software with other methods.
He explains that Morton thought that the natives of New Guinea were 'negroes'. Poor Morton - under attack again. I had hoped that with Gould's death he would get some peace.
The first racial classification of New Guineans I read was Coon's in the sixties. Even back then no one thought New Guineans were closely related to Africans. And Wade doesn't say that. Smith has to dig up a classification from 1839 to attack Wade. He seems desperate to smote Wade hip and thigh.
This is becoming psychodrama.
I do not see much point in working so hard to try to convince anthropologists that there are 3 races instead of 14 "populations," considering that nothing would convince them. I am not convinced that it is a scientific debate. It is just semantics, and does not deserve to be dignified. We should ask the anthropologists how creating more divisions within humanity is "progressive." Perhaps the best tact is to ignore them and continue the science and medicine.
Since the so-called "HBD community" mostly bought into the GWAS-Jihadist propaganda, thanks to tools like Razib Khan and Steven Pinker, they have allowed themselves to be driven into vague, unwinnable debates over population genetics, heritability, and the meaning of race. They do not realize the power of specific molecular genetics knowledge to persuade. Wade never bought into this propaganda, and he did not screw up his discussion of MAOA, like Pinker and John Horgan did.
The one criticism I would make of Wade's discussion was claiming that MAOA's effect could be balanced by other genes. We still do not know the total effect of MAOA because it has many environment and hormone interaction effects, promoters, SNPs, epistasis, etc., which have never all been studied simultaneously. If other genes are as powerful as MAOA, I would expect other syndromes caused by them similar to Brunner syndrome.
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