Historical Determinants of Contemporary Attributes of African Descendants in the Americas: The Androgen Receptor Holds the Key

WD Aiken, PubMed, October 1, 2011

Abstract

It is hypothesised that seemingly disparate and unrelated phenomena clustering in persons of African descent living in the Americas such as outstanding sprinting ability and high prostate cancer incidence and mortality are in fact related and emerge from enhanced testosterone responsiveness in descendants of African slaves surviving the transatlantic trade in Africans. It is postulated that the ability to have survived the middle passage was positively correlated with greater responsiveness of the androgen receptor to its primary ligands dihydrotestosterone and testosterone, and that slaves possessing more responsive androgen receptors experienced a survival advantage engendered by the enhanced anabolic effects which accrued such as increased red cell mass and therefore greater oxygen carrying capacity and tissue oxygen delivery enabling these slaves to tolerate stifling conditions in the hull of the slave ship, increased lean muscle mass and therefore greater surface area to volume ratio resulting in easier ability to dissipate heat and remain cool, and increased skin thickness and sebum production resisting the macerating effect of lying in admixed bodily fluids below deck. These androgen effects as well as others would have produced a survival advantage under the severe selection pressure created by the inhumane and physiologically challenging circumstances under which the slaves were transported from the interior of the African continent and West Africa to the ‘New World’. This would result in a population shift favouring increased androgen receptor responsiveness in descendants of African slaves populating the Americas and a corresponding geographic and racial distribution of androgen related phenomena such as sprinting prowess and prostate cancer. African-Americans having the highest prostate cancer incidence rate and the Caribbean having the highest prostate cancer mortality rates in the world are consistent with this hypothesis as is the observation that the 10 fastest men and 9 fastest women of all time are exclusively the descendants of West African slaves who survived the middle passage. It is predicted that as yet undiscovered as well as known biological correlates of enhanced androgen receptor responsiveness such as relatively short CAG-repeats in the poly Q tail of exon 1 of the androgen receptor gene will be more prevalent among African-Americans and Afro-Caribbean peoples than among West Africans. It is also predicted that African-Americans and Afro-Caribbean peoples will have relatively shorter CAG-repeats in the androgen receptor gene compared to West Africans.

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  • Anonymous

    More psycho babble. Africans are African all over the world, no matter how you try to make excuses or try to make one group better than the other. Of course some people will use the old slavery stand-by to instill more White guilt and give Africans an excuse to milk us dry even more. Don’t fall for this garbage.

  • Anonymous

    Uh….If I remember correctly, Black Africans have higher T than African Americans. The blacker they are the higher the T. I think that is a given.

    So there goes your “theory” on the slave trade being to blame. They always look for a way to blame whites for pretty much everything.

  • Anonymous

    “It is hypothesised that seemingly disparate and unrelated phenomena clustering in persons of African descent living in the Americas such as outstanding sprinting ability”

    And all the idiot intellegentsia thought the outstanding sprinters were East Africans who still live in Africa and are not relation to the W. Africans 2,000 miles away who were taken to America.

    Glad they used that word hypothesised. Doubt they will find proof.

  • Anonymous

    The middle passage was no worse for them than it was for the Europeans. Magellan, Vasco de Gama, Drake and all the early global circumnavigators right up to the mid 19th century often lost 90 or more percent of their original crew.

    Genetics are genetics. A rough time for 2 months for some ancestors 300 years ago is not going to change anything.

    Unless the slave ships ran into a hurricane the Europeans on the north atlantic ships always had a worse time because the north atlantic is far worse to sail across than the mid atlantic.

  • Anonymous

    Alternatively, the selection pressure may have been the result of differential capture for sale by other Africans.

  • Anonymous

    ” androgen receptor to its primary ligands dihydrotestosterone and testosterone, and that slaves possessing more responsive androgen receptors experienced a survival advantage engendered by the enhanced anabolic effects which accrued such as increased red cell mass and therefore greater oxygen carrying capacity and tissue oxygen delivery enabling these slaves to tolerate stifling conditions in the hull of the slave ship, increased lean muscle mass and therefore greater surface area to volume ratio resulting in easier ability to dissipate heat and remain cool, and increased skin thickness and sebum production resisting the macerating effect of lying in admixed bodily fluids below deck. ”

    I’m a nurse. I took physiology. It would take generations for

    androgen receptors to achieve what this article claims.

    “increased lean muscle mass and therefore greater surface area to volume ratio resulting in easier ability to dissipate heat and remain cool,”

    This would never happen in a few months.

    They probably were seasick. Probably had little appetite when not actively seasick. Africans were not fat. They would have lost all the spare fat in the first 2 or 3 weeks. Then with continued lack of appetite and seasickness they would have lost, not gained lean muscle mass.

    What do I know? I’m only a nurse, but from my basic knowledge of physiology I can’t see it.

    Have these people never heard of paragraphs?

  • Anonymous

    Nothing about the large amounts of White DNA in the American black population. That is the usual explanations for differences between Africans and African Americans.

    That excess testosterone is a problem for the entire country. It’s the cause of so much crime, riots and general disfunction.

  • Anonymous

    ” descendants of West African slaves who survived the middle passage.”

    Interesting theory, but needs data about the descendants of West African slaves that did not survived the middle passage?

  • Rhialto

    Assuming the differentials between African-Westernhemispherians and African-Africans is correct, I make an alternative hypothesis: That muscularity, good health, and other correlates of the discussed genes made certain individuals desirable as slaves. These were the ones that the slave wholesalers bought, and then transported to consumers in the west. The rest were used for purposes within Africa.

  • Anonymous

    This is hysterical! One unfortunate boat ride forever changed a person’s body chemistry?

    How about they are good sprinters because they spent thousands of years running away from some of the largest and most vicious wild animals to be found in the world? Anyone with eyes can see the large muscle mass on their rears is different from whites. This is because they developed differently over time. The real question is did they originate differently?

  • Physiologist

    “increased lean muscle mass and therefore greater surface area to volume ratio resulting in easier ability to dissipate heat”

    Oh… Quite a dubious statement. The easier ability to dissipate heat depends on greater surface area to volume ratio that is higher in SKINNY individuals. They could hardly benefit from increased muscle mass (whatever “lean” it would be).

  • Anonymous

    “This is hysterical! One unfortunate boat ride forever changed a person’s body chemistry?”

    Not only that, but that of all all their descendants to the end of time. This is a US government publication.

  • John Engelman

    This is so poorly written that it reads like an essay written by an undergraduate trying to sound profound.

    I have read that as many as one third of blacks who were transported to the New World died along the way. It certainly is plausible that those who survived were more athletically gifted than those who died, and had higher testosterone levels.

    Nevertheless, African blacks seem to be at least as athletically talented as American blacks. If they are less prominent in international sports competition that is because they have fewer opportunities to develop their talents.

  • Deirdre

    It’s amazing what lunacy these researchers can come up with. Perhaps they should try their hand at science fiction. It may be far more lucrative for them. I agree with the post exclaiming how utterly ridiculous is the idea that evolutionary change can take place after a trip over the ocean.

  • Anonymous

    This fits right in with black former Representative Major Owens’ contribution to African America history that asserts that 200 million slaves were toss overboard causing the sharks to change their historic feeding habits.

    The enhanced testosterone in the blacks got into the system of the sharks and made them multiply and also dumb down their instinctual feeding habits causing them to still stick around to this day waiting for more blacks to eat.

  • Anonymous

    I’m a nurse. As far as I can remember, relaxation of ligands has something to do with prostate cancer progression. There are drugs that control the ligands that stops cancer progression.

    This article seems to say that prostate cancer is caused by androgen receptors acting on ligands.

    Whatever the physiology, 6 weeks on a boat wouldn’t change a person’s physiology. Nausea, diarrhea, weight lose, skin rash, eye infections, some muscle atrophy from inactivity would be the common health problems.

    A few weeks on shore with good food and normal exercise would get them back to normal.

    By the time the Cajuns sailed to Louisiana from Nova Scotia they could hardly walk.

  • sbuffalonative

    There’s a similar theory that the reason American blacks have higher rates of hypertension is because they are the descendents of captured slaves who could tolerate high concentrations of salt during the trip the the New World (or something close to this). Below is a link with an excerpt which says this theory is a myth:

    “Fryer’s notion that there might be a genetic predisposition at work was heightened when he came across a period illustration that seemed to show a slave trader in Africa licking the face of a prospective slave…,” wrote the profile’s author, Stephen Dubner. “A person with a higher capacity for salt retention might also retain more water and thus increase his chance of surviving. So it may have been that a slave trader would try to select, with a lick to the cheek, the ”saltier” Africans.

    http://raceandgenomics.ssrc.org/Kaufman/

  • Anonymous

    11 is right. Muscle is all lean. The fat is on top of the muscles. The 2 don’t mix.

    I’ve read so many learned discussions that claim the reasons Somalians, Sudanese, the Dinkas and some other Africanss are so tall and slim is to dissipate heat better. So the quicker they lost weight on the ships the better it would be for heat stroke.

    There are no explanations for the fact that there are a lot more Bantu people in Africa. They are medium height and medium to stocky build. They evolved in the same climate.

    Then there are all those tall, skinny Germans, Scandinavians, Czechs, Russians, Poles and other Northern Europeans. They must be tall and skinny to conserve heat. Or to wade through the snow.

    Any thing to bring up the evils of Whitey.

    I think the purpose of this is to show that the only reason blacks have higher prostate cancer rates than other races is because of what evil Whites did to some of their ancestors for 2 months of their lives 300 years ago.

    Wonder why Asian men have high osteoporosis rates. Evil Whitey must have done something evil and monstrous.

    Maybe Marco Polo and the other Venetian traders brought osteoporosis germs with them and infected the Chinese who spread it to the others. Or those evil monks Emperor Justinian sent to steal the silkworm eggs.

    All evil on the face of the earth has been done by Whites according to Professor Noel Ignatieff of Harvard University.

    Once Professor Ignatieff’s program of extermination is carried out, the non Whites will live happily ever after.

  • Anonymous

    12 — Anonymous wrote at 8:55 PM on October 19:

    “This is hysterical! One unfortunate boat ride forever changed a person’s body chemistry?”

    ************************

    Comprehension people! Why try to look ridiculous to outsiders if we don’t have to by such comments?

    The Africans that already had those particular attributes were the ones who survived the middle passage and lived to breed and produce more of the same, now known as African Americans.

    Read the first sentence again–carefully.

  • CDE

    I agree with #6, in that these alleged changes (notice they don’t use the word “mutations, but that’s what it really would be) would take many generations, not mere months.

    Also, what about the Irish? Thousands of Irish peasants (my ancestors included) were shipped over to Barbados and Virginia to be used for slave labor years before the African slave trade began. Later, during the Irish famine of the 1840’s, thousands more were shipped over in conditions as bad or worse than what slaves experienced. And what about the prison ships sent to Australia? The trip was much longer and I doubt they had first class accomodations. Logically, the same changes should have occured in all people who experienced hardship on the “middle-passage.”

  • Anonymous

    My theory based on obersvation is that black males seek out the most physically robust women in a population. By this I mean the most endowed, with musculature suggestive of physical dominance. They have continued this breeding trend to the detriment of themselves by excluding pretty much all other relevant variables when selecting a mate. The end results is a hulking, physically overbred race of hormonally overcharged indviduals who can’t help but act out in ways that they were essentially bred for.

  • Anonymous

    19 — Anonymous wrote at 10:41 PM on October 19:

    “The Africans that already had those particular attributes were the ones who survived the middle passage and lived to breed and produce more of the same, now known as African Americans.

    Read the first sentence again—carefully.”

    Poster 19. I’m a nurse so I read it from a physiology medical point of view. It is basically about prostate cancer. The author blames higher rates of prostate cancer in blacks on the fact that they came to America on those slave ships.

    Black africans have the same high rates of prostate cancer. There are entire charts of ethnic groups and their hereditary diseases.

    A couple months would not change the physiology of anyone. Disease and injury are not serious changes in physiology.

    Evolution and change takes generations.

    The only real lasting medical problem I can see would be cases of real malnourishment with 8 to 14 year olds. They might or might not grow up a bit smaller than they would have if they had been well nourished for those 2 months. It would not be much, at most 2 inches and 20 pounds smaller.

    The slave ships had a higher survival rate than the explorers and free immigrants. It is disgusting to think of, but remember, the slaves were very, very valuable. A young strong man cost about $1,500 back in 1800 when a good income for a small family was about $100 per year.

    Ever seen Abraham Lincoln’s home in Springfield Ill?

    It is not a mansion, just a nice middle class house for a prosperous but not really wealthy lawyer. 2 stories, 8 or 9 rooms on an acre lot. It cost him $1,600 in the 1840’s.

    A young strong man sold for about $2,500, a woman $1, 200 to $1,500 in the 1840’s.

    Slaves were very valuable commodities in those days.

    The death rates on slave ships were low. Ever been on some of those ship museums and seen the crew’s quarters? They slept in shifts. They stayed on the ships for years with only a few days shore leave occasionally.

    The English sent 6 year old boys on the ships and worked them hard. If they died it was no problem. The boys cost nothing to aquire and there were plenty more back in England.

    Those boys worked on the navy ships supplying gunpowder to the cannons. They were tunnels built between the powder supply and the cannons. The boys crawled back and forth during battles.

    Between battles the boys cleaned, learned the hard seaman’s trade and served the sailor’s sexual needs. Those powder monkeys as they were called had a higher death rate than the slaves. Of course they were on those ships for years at a time.

    Life on a slave ship was rough, but it was only 6 or 8 weeks.

    The death rate was low compared to other ships.

    The Captains were paid a bonus for every healthy slave delivered.

    They were fined for deaths with lesser fines for diseased and injured slaves. Suppose you ordered a truck load of strawberries. If they arrived all rotten and smashed due to negigence would you pay for them? Would you use that vendor again?

    If your employee broke a lot of your goods wouldn’t you take it out of his or her paycheck? Why would a slave ship owner allow the sailors to treat the slaves so badly that his valuable cargo would die or be sick and disabled?

    Some of the black historians claim that the slave ships were similiar to the concentration extermination camps set up by the Germans and Japanese during WW 2 or equilevant to the Bataan death march. Just another liberal lie.

    Slave societies take care of their valuable property. Capitalist societies don’t take care of their infinite supply of labor.

  • Anonymous

    13 — John Engelman wrote at 9:03 PM on October 19:

    This is so poorly written that it reads like an essay written by an undergraduate trying to sound profound.

    I have read that as many as one third of blacks who were transported to the New World died along the way.

    I’m sure you read that John, but I doubt it is true.

    The writing is standard medical research writing. Be glad you don’t have to read med research to make a living.

  • Anonymous

    Can someone explain why nut cases like the guy who let loose the wild animals in Ohio invariably happen to be white?

  • Anonymous

    Oh good grief…such disturbing logic. Slavery does not make people inherently have more testosterone, whether on an individual level, or on an evolutionary level.

  • John Engelman

    14 — Deirdre wrote at 9:06 PM on October 19:

    It’s amazing what lunacy these researchers can come up with. Perhaps they should try their hand at science fiction. It may be far more lucrative for them. I agree with the post exclaiming how utterly ridiculous is the idea that evolutionary change can take place after a trip over the ocean.

    ——-

    Individuals do not evolve. Populations evolve. If the trip over the ocean selected for certain innate characteristics, it would have influenced the innate characteristics of the survivors, and their descendants. There is little evidence that this happened, however.

  • olewhitelady

    Surviving a slave ship did not make anyone stronger or more viable. It was simply a matter of survival of the fittest, and those fit people passed on their genes, while those who died of course did not. It’s the same throughout the history of the planet. Stress might cause the immunity system of one individual to be compromised, but he does not pass this problem on to his offspring.

  • interesting times

    I’ve heard this kind of speculation since the sixties and love it because it expresses common knowledge of the advantage blacks have in specific areas of physical activity; they dominate two professional sports from a pool that comprises %7 of the U.S. population. So large numbers of otherwise non-race realists admit that there is a genetic component. The fun starts when they begin flailing for an answer.

    Occam’s canon says that the simplist answer is often correct.

    I doubt that one selection event through a decimating ocean voyage is enough to create the atheletes we see now. The other condition that is usually brought into the picture is the general field labor, done in a high heat, high humidity environment.

    There is no reason to believe that either of these selections would produce what we observe today. They have these genetic traits from thousands of years in Africa.

    Fast twich muscle fiber, while useful in sprinting, and many pro sports is not needed in field labor. Low body fat and efficient sweating with a salt retaining mechanism is advantages for activity in the American south. High t, well thats just a problem for us, adding to violent impulse and incompatable with European sexual mores. The ease with which blacks can slip from conscious resraint into limbic system mode is very much an advantage in athletics, disorganized crime and low self consciousness in social activities. The genes blacks carry are a result of sexual and environmental selection, in Africa.

    Besides once again pinning everything good or bad on whites, These slavery selection fantasies also imply that the other races never went through traumatic blips in their histories or ever worked hard.

  • dtb

    It is obvious to me and anyone else who has read “Erectus Walks Amongst Us” that the higher testosterone levels are genetic. Also, anyone who knows real history is aware that more slaves were sent to South America than North America.

  • arcadian

    I don’t have any numbers but i would be willing to bet that a greater percentage of Cajun people on the way to Louisiana, and Irish people on the way to Australia, and Puritans on the way to Jamestown (and the ship crewmen) died than the percentage of Africans on slave ships on the shorter voyage across the mid Atlantic. Not to mention the crab fishermen and oil rig and boat workers who die every year to this day.

    I have begun studying the characteristics of people who dwell near the coast and work on boats. Contemplate the term “sea legs”.

  • Anonymous

    I think the theory is that the slave ships were a severe “bottleneck” such that survivors, to be survivors, must have had pre-existing characteristics. Not such a farfetched hypothesis, but unlikely since survival likely depended on many unknowables including weather, temperament of the ship captains, and resistance to virus plagues. Anyway evolution does not assert as much of an effect on human populations as popularists imagine. All human breeding populations breed to the optimal point, not the maximal point which is required for classical natural selection to function. In other words, we are all eugenicists, we just are not all equally good at producing highly intelligent progeny – or whatever characteristic is desired. People are predictably hypocritical about this.

  • Anonymous

    The trip to Australia took 5 or 6 months. I’ve never read that the Irish English Australian descendents of the convicts who died in far greater numbers have any problems stemming from what an ancestor went through for 6 months of a live time.

    6 or 8 weeks can’t do anything to a person’s physiology, let alone the descendants 300 years later.

  • margaret

    Here is an example of the horrors of ocean travel.But these people are not just White, but the most hated of Whites, the nordic blue eyed whites.

    Coffin Ships

    During the Famine period, an estimated half-million Irish were evicted from their cottages. Unscrupulous landlords used two methods to remove their penniless tenants. The first involved applying for a legal judgment against the male head of a family owing back-rent. After the local barrister pronounced judgment, the man would be thrown in jail and his wife and children dumped out on the streets. A ‘notice to appear’ was usually enough to cause most pauper families to flee and they were handed out by the hundreds.

    The second method was for the landlord to simply pay to send pauper families overseas to British North America. Landlords would first make phony promises of money, food and clothing, then pack the half-naked people in overcrowded British sailing ships, poorly built and often unseaworthy, that became known as coffin ships.

    The first coffin ships headed for Quebec, Canada. The three thousand mile journey, depending on winds and the captain’s skill, could take from 40 days to three months. Upon arrival in the Saint Lawrence River, the ships were supposed to be inspected for disease and any sick passengers removed to quarantine facilities on Grosse Isle, a small island thirty miles downstream from Quebec City.

    But in the spring of 1847, shipload after shipload of fevered Irish arrived, quickly overwhelming the small medical inspection facility, which only had 150 beds. By June, 40 vessels containing 14,000 Irish immigrants waited in a line extending two miles down the St. Lawrence. It took up to five days to see a doctor, many of whom were becoming ill from contact with the typhus-infected passengers. By the summer, the line of ships had grown several miles long. A fifteen-day general quarantine was then imposed for all of the waiting ships. Many healthy Irish thus succumbed to typhus as they were forced to remain in their lice-infested holds. With so many dead on board the waiting ships, hundreds of bodies were simply dumped overboard into the St. Lawrence.

    Others, half-alive, were placed in small boats and then deposited on the beach at Grosse Isle, left to crawl to the hospital on their hands and knees if they could manage. Thousands of Irish, ill with typhus and dysentery, eventually wound up in hastily constructed wooden fever sheds. These makeshift hospitals, badly understaffed and unsanitary, simply became places to die, with corpses piled “like cordwood” in nearby mass graves. Those who couldn’t get into the hospital died along the roadsides. In one case, an orphaned Irish boy walking along the road with other boys sat down for a moment under a tree to rest and promptly died on the spot.

    The quarantine efforts were soon abandoned and the Irish were sent on to their next destination without any medical inspection or treatment. From Grosse Isle, the Irish were given free passage up the St. Lawrence to Montreal and cities such as Kingston and Toronto. The crowded open-aired river barges used to transport them exposed the fair-skinned Irish to all-day-long summer sun causing many bad sunburns. At night, they laid down close to each other to ward off the chilly air, spreading more lice and fever.

    Many pauper families had been told by their landlords that once they arrived in Canada, an agent would meet them and pay out between two and five pounds depending on the size of the family. But no agents were ever found. Promises of money, food and clothing had been utterly false. Landlords knew that once the paupers arrived in Canada there was virtually no way for them to ever return to Ireland and make a claim. Thus they had promised them anything just to get them out of the country.

    Montreal received the biggest influx of Irish during this time. Many of those arriving were quite ill from typhus and long-term malnutrition. Montreal’s limited medical facilities at Point St. Charles were quickly overwhelmed. Homeless Irish wandered the countryside begging for help as temperatures dropped and the frosty Canadian winter set in. But they were shunned everywhere by Canadians afraid of contracting fever.

    Of the 100,000 Irish that sailed to British North America in 1847, an estimated one out of five died from disease and malnutrition, including over five thousand at Grosse Isle.

    historyolace.comworldhistory/famine/coffin.htm.