Genetics, Puberty and African American Girls

Scott H., 23 and Me, June 17, 2013

Several studies have shown that certain girls, particularlyAfrican-American girls, experience puberty earlier than others, but there’s an ongoing debate about what that might mean.

There are a number of reasons why some girls begin puberty earlier than others. Girls who are heavier tend to enter puberty earlier than thinner girls, while there are also disorders that can trigger “precocious puberty“—or puberty before age eight. Environmental factors, such as nutrition and certain chemicals, also can play a role.  {snip}

But to date, the scientific community has all but overlooked a core population that is perhaps most at risk. Today, African-American women tend to begin menstruating four to six months earlier than girls of European descent. Later in life African-American women also have a higher risk for obesity, hypertension, and metabolic disorders including diabetes. These two trends could be related and genetic factors could be a common denominator.

new study of African-American women looked specifically at genetic variations contributing to  age at menarche. The research, done by a multi-institutional team of scientists, crunched data from 15 different studies, which included information from over 18,000 women.

Their findings indicate differences in DNA that could help scientists better understand the genetics of menarche timing in all women, as well as the development of diseases associated with early menarche.

{snip}

In this case study, the researchers performed a meta-analysis of existing research to search for DNA variants associated with earlier menarche in African-American women and then compared their results to data from women of European descent. The variants, called SNPs (or single-nucleotide polymorphisms), can account for some of the differences in biological traits, in this case early menarche, between two individuals. {snip}

Out of 42 SNPs associated with age at menarche in European women, 25 were also associated with the trait in African-American women, bolstering the evidence that these genes genetic variants are tied to menarche timing. However, they also found variants in eight regions of the genome that were more strongly associated with age at menarche in African-American women than in European-American women. Many of these regions contain genes that influence obesity, underscoring the link between body fat and early menarche. Other regions include genes associated with breast and other cancers.

{snip}

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  • David Ashton

    There are probably genetic reasons for maturity time-scale differences between black and white males too.

    • me

      When you transport a jungle-dwelling humanoid into the European American culture, you’re going to see glaring differences in both genetics and behavior. Why are people constantly shocked and enraged by the truth? The feral Bantu, in their natural habitat, have a lot of natural enemies. The lion…the tiger…the great ape…each other…..so, it makes sense that they have to ramp up the birth threshold.

      • /.murphy

        Tiger? In Africa? What planet are you from?

        • me

          Not the false avatar, intellectually myopic, and humorless one you seem to be from….

        • MikeofAges

          Don’t worry about the tigers. Always, the most serious enemies are the ones you can’t see and things
          you can barely see that vector them. You have to look to those issues,
          what food is available and the physical habitat. Plus, there’s the issue
          of what you have to work with. For tens of millions of years, there have
          been environments where humans could have thrived. But no humans. Just
          because something is a good idea doesn’t mean it happens. Not in
          evolution.

    • Bossman

      Those genetic differences came from differences in climate and geography over a long time-span. Blacks could have a few things to contribute to the gene pool.

      • blight14

        Like what? I fail to see what ‘benefit’ we could garner from outdated farm equipment….

        • Bossman

          I read that Blacks have stronger bones, stronger skin that ages less fast, better basal metabolism, less cholesterol gets deposited in their arteries, better eye-sight, better hearing, better taste buds, stronger sense of smell, more muscular bodies, stronger sexual drives, less of a tendency to be gay. In the distant future, humanity will try to produce the best kind of people and cross-breeding may be one of the tools that they will use.

          • HJ11

            Nope. It becomes an engineering problem. You can’t fit all supposed good things into the package. It’s like those cars that are also airplanes that you see sometimes. They’re not very good cars and they’re not very good airplanes.

            This also gets into general vs specific adaptations. Whites have more general adaptations that other races. This is a good thing and gives us a survival advantage. In other words, we are not like Koalas who will die out if they don’t get the leaves of just one type of tree.

            When things change, we adapt.

          • MikeofAges

            At last, someone who understands evolution. Evolution cannot do just anything. It work only with what is there already and can only refine within the potentialities already inherent in the existing gene pool. Think of everything that didn’t ever happen and reason why.

          • Bossman

            All humans belong to the same species and humans have brains that they can use to direct and influence their own evolution. Human population groups are also less geographically isolated than they used to be.

          • MikeofAges

            But genotype flows only one way, from the Third World to the West. The last imperialist group which genetically imprinted itself on its subject people on a mass and universal basis was the Spanish in the Americas, 500 years ago.

            Out of colonial experience came the dictum that traditional cultures fall apart in the face of contact with advanced civilizations. That may be true of small, isolated societies, but not of the large mass. As often, advanced societies fall apart in face of invasion by intractable barbarians populations. In the Hispanic “invasion” America is not getting the worst of it. Thanks to the Spanish, Hispanics arrive speaking a Western language, adhering to Western religion, and pre-assimilated into Western civilization.

          • Bossman

            Yes, culturally and genetically, Hispanics from Latin America are already partly Westernized. What is desirable and what is attractive? Intelligence and physical beauty will always be of great value and have advantage.

          • MikeofAges

            Talking about what people actually do.

          • The Euro-Asian human brain is what makes us so adaptable. It’s open-architecture so long as religion doesn’t get too much in the way.

          • MikeofAges

            Then you’re talking about rebooting the human race. No guarantees what hand you will get when shuffle the deck and deal.

            One thing I have thought about is what would happen if you created new, homogenous breed of human that was say 20 percent black African, 75 percent white European and 5 percent other, largely Amerindian, in descent.

            You might end up with a rough type, adequately intelligent, I am sure, but coldly competitive and morally indifferent. Maybe there’s some design on the part of the “secret” government in flooding North American with East Asian immigrants.

            You always get a different picture depending on your perspective. What you see in a hundred years and what you see in 5,000 years could be very different. Whatever happens, whatever people are here in the distant future will be roughly the proportionate descendants of whomever is here now and whomever comes in the future.

          • David Ashton

            Have a look at Brazil and think ahead.

          • MikeofAges

            Believe me, I have looked ahead.

          • David Ashton

            This wasn’t meant as a criticism. There is no positive signs about future miscegenation in Brazil, and the recent rioting is not a good omen in the short term.

          • Romulus

            The “research” validity should be vetted. Example, the Watusi are very tall bean poles, whereas the old northmen are the tallest/ biggest people in the fossil record. It explains why they consistently win the Ironman competition sports. ( magnus vermagnasson). Check WHO authored the study. Its possibly laced with inconclusive (spin) inferences and PC.

          • David Ashton

            The most important feature will be the mental capacity to solve problems. Crossbreeding with Blacks will not assist this result. Carefully selective breeding by government, i.e. state eugenics, is a possibility that may require some crossing between related or compatible groups, but genetic research by then should have investigated the problem of outbreeding depression, climatic adaptation, and ethnic propensity to particular diseases. There has been no serious biological study of crossbreeding since the 1960s.

      • MikeofAges

        And where do we find the mad scientist who’s going to manage this process anyway? Are you proposing genetic surgery? Selective breeding? Natural selection? Isolating a breeding population with a carefully selected mix? Darn, you can’t just say that something is possible. You have to talk about whether plausibly it can happen, and, if so, exactly how. If there’s no “how”, then it is not what is going to happen. Not to mention, do people have no right to preserve their kind and culture? Or is all and everything subservient to the goal of creating a “new” man?

        Nothing new in this stew pot.

  • HJ11

    Black babies (as is also the case with chimps) seem to be more intelligent than White babies for a few months after birth. The evolutionary reason may be that nature has determined that under normal African circumstances, the Black babies and the chimps must learn to fend for themselves at an earlier age. Whites mature more slowly and this be nature’s way of letting us develop more brainpower, among other things.

    • Sqeptique

      I will never forget seeing an African woman carrying around her baby by one arm like he was a loaf of bread. Amazingly the little tyke wasn’t bothered at all by being hoisted off the ground and dangling by his arm. I don’t know why but the image of that has stayed with me for decades. Whites handle their infants very carefully and delicately. This little African was being handled like an old rag doll. Just hanging there by one arm.

      • me

        Monkeys do that, too.

      • Robert Griffith

        I coughed my soup up in laughter when I read your post. LOL!!!! So very true as well. When in their natural environment, the differences between the natives of certain parts of Africa and that of the higher apes become blurred. And I am not trying to be nasty or racist. Just stating the truth.

  • APaige

    Having an early menstruation cycle is a relative, cultural construct.

    • David Ashton

      “One is not born a woman” (Simon de Beauvoir).
      Hormones, ovaries, vaginas, breasts and placentas are all imagined social constructs of the oppressive white male patriarchy (which is not socially constructed, apparently).

      • MikeofAges

        Don’t forget to add the female brain to the list. Scientists and doctors experienced in looking at brains can tell instantly whether a brain came from a male or female.

        However, and don’t forget, Herb Cain (1916-1997), the San Francisco Chronicle’s longtime gossip and entertainment columnist once wisely said, “The brain is a grey organ which lives in a dark place about which little is known, and it should stay that way unless absolutely necessary.”

        Stick to that rule in daily life. Judge the cause by the effect, and judge the effect, not the cause.

  • Stentorian_Commentator

    This reminds me of what I’ve heard about Africanized honeybees. It must start with an Africanized drone, but if a non-Africanized queen bee lays eggs of Africanized and non-Africanized future queens, the Africanized ones develop first and kill off the other potential competitors before they’re born. And when we look at birthrates here, it is important not only to look at the number of children per ho’, but also the periodicity – a new African generation every 15-16 years versus now about 30 years for whites. Another good reason to shoo them back to Africa.

    • me

      “Shoo”? LOL! Have you ever tried to ‘shoo’ a Bantu?

      • You can’t. I have had them come at me diagonally across the street from a block away because I was smoking a cigarette. The only way to get rid of them is 911. They see you do that and it is scurry time.

        • blight14

          911 OR put a ‘1’ in front and you have 1911, they work well too……

  • Erasmus

    Their findings indicate differences in DNA that could help scientists better understand the genetics of menarche timing in all women, as well as the development of diseases associated with early menarche.

    You mean not everyone is the same???? Who’d a thunk it? Aren’t we supposed to celebrate diversity?

    (sarcasm off)

    • evilsandmich

      That’s the real story: signifigant genetic differences between races. Those researchers better keep that plane ‘close to the deck’ so that they can avoid PC anti-air defenses.

  • The__Bobster

    Wow, someone finally notices that Nubian princesses reach prime breeding age at 11-12? Did they notice that the sheebs also have an eight-month gestational period?

    • Dontavious noticed Nubian princesses were ripe at 11-12 when he was age 10.

    • AllSeeingEyeSpy

      no wonder my baby was born early. . . Is this article saying, that since black girls reach puberty 6 months earlier, it’s only natural they should push out 3 times as many babies? Seems like it is. . . .

  • Winston

    Africans also have a shorter gestation period than Europeans. The prevalence of premature births to those of African descent is often incorrectly attributed to this, I’m guessing.

    • evilsandmich

      I wonder too if the ‘light that burns twice as bright burns half as long’ as a former black cleaning lady was complaining about menopause…at 35.

  • George

    J. Phllip Rushton was clear in his works.
    There is a continuum of black-White-Asian.
    Blacks gestate faster and are more-fully developed at birth. They mature faster. They reproduce sooner than whites, who do so sooner than asiatics.
    This isn’t news to anyone who has studied the biological differences between races, or those who pay attention to the research.

    The negroid subspecies adopted a more fecund approach to producing the next generation. When one is more likely to be chased by cheetahs, this is a common-sense approach.
    It means, among other things, that their intellectual growth is stunted. The body that invests in denser bone mass and more fast-twitch muscle cells leaves little for cranial capacity or higher cognitive ability.
    The net result is Detroit. Memphis. New Orleans. East St. Louis. Sub-Saharan Africa in toto.

    • NordicHeritage

      And this is why the powers that be want more and more nonwhites. They are easier to manipulate to whatever end the elites want.

    • BonusGift

      Personally I think the ‘continuum’ thing is overdone and a gross oversimplification (e.g., especially on a population adjusted basis whites dominate across the broad spectrum of sports and real intellectual challenges); but certainly there are significant differences between the races and it matters.

  • blight14

    Margaret Sanger was 100% correct…..we failed to heed her infinite wisdom…………

  • Bossman

    No! They definitely are not a master race. They do have weak kidney functions. They sweat more and urinate less. Their weak kidney functions contribute to heart disease and other vascular diseases but they have less of the hardening of the arteries due to their better ability to metabolize sugars and fats and hence have less cholesterol deposits in their arteries. Nature selects what works for a particular environment and has no idea what a master race is and maybe couldn’t care less about that.

    • David Ashton

      Yes, selection for diverse environment is the evolutionary process.
      This must be considered in eugenic planning for the human species as a whole.

  • MikeofAges

    The thing about the athletic career is that it is short. If you wait to long to start it, it is already too late. Greater maturity presumably is an advantage. Have heard, in Canada, where youth hockey players are assigned to a level based on their age as of Jan. 1, those born earlier in the year have a considerable and enduring advantage simply because they come into each season, on the average, more mature than those born later in the year. Because the athletic career is so short, its course can be affected, even derailed, by some quirky factors, even (dare we say so) politics. Politics within the program or organization. Or the big kind of politics.

  • His Africa vacation is going to cost over $100 million.

  • A leopard is a slender, fast-mover that is nothing like an Asian tiger. Asia’s tiger is a little bigger than an African lion, but the South American jaguar is close to both. I don’t think jags attack humans. They’re territorial, very careful, and will watch people and follow them, but they seem to be smart enough to know that even South American Indians are also apex predators.

  • ravitchn

    All the more reason for blacks to be taught some basic Christian morality. They have stopped going to church as they once did massively and many of their churches have become less Christian and more centers of racial agitation, much like Obama’s church in Chicago under the Reeeeeeverend Wright.

    • Dude

      Whites shouldn’t waste our time trying to teach blacks anything. We should look after our own.

  • David Ashton

    This seems to be the case with infants within particular races as well as between them.

  • Paleoconn

    Girls who have a dad present and are close to them develop later than those who don’t. This could explain it, too.

    • Dude

      But blacks are well known to mature faster than Whites in every other way. Are you sure what you’re referring to is a causal correlation anyway?

      • Paleoconn

        There have been studies on this subject that I discovered via Dr. James Dobson who is an expert on raising children and the phenomena surrounding puberty and their maturity, physical and behavioral.

    • Bossman

      I read the opposite thing happens. Girls who grow up without mothers and are around men a lot mature faster.

      • Paleoconn

        Not just any man, their biological father. A voice and a presence that they recognize since before birth. The pheromones the father emits has a lot to do with it.