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View Full Version : R1b domination in West Europe due to immunity for some diseases?



Goga
08-11-11, 18:58
When Europeans (and especially Spaniards) colonized South America, many native SA died because Europeans brought deadly diseases with them into the New World.

Now, let assume that R1b is from the Northern Caucasus / South Ukraine northern regions of the Black Sea. And that the most of the folks here are right.

Is it possible that when R1b migrated into Europe they also brought unknown diseases with them that killed most of the indigenous Paleolithic European population?

Or that the distribution of the haplogorups and the domination of R1b occurred due to the Black Death in Europe. "The Black Death is estimated to have killed 30–60 percent of Europe's population." http://en.wikipedia.org/wiki/Black_Death

And that R1b survived miraculously the Black Death and that the 'survival of the fittest' of Charles Darwin was here at work.

Or is this just a fantasy that belongs in the fantasy books..

Mzungu mchagga
08-11-11, 19:28
Usually a transmission of a lethal disease from an immune population to a non-immune population occurs when both populations have been previously isolated for a very, very long time. Of course without contact populations in between them. This wasn't the case on the Eurasian landmass, at least not from the Caucasus to the Atlantic Ocean.

As far as I know, but other forum members surely know better, the Y-DNA has nothing to to with the immune system directly (otherwise there should be pure male or female diseases only, apart from prostate or uterine carcinoma). It could only be that populations carrying a certain Y-DNA have also a higher prevalence or risk of certain diseases. For instance, I try to recall to have read somewhere that haplogroup I1 is somewhat higher at risk for HIV, and if infected, AIDS will progress a little faster.

This of course could have been the case in Europe then! But, --> could someone please show the charts again of the percentages of paleolithic and younger autosomal DNA among European populations?
Because then, it would really prove that only the male linages disappeard, but not the whole paleolithic society!

Goga
08-11-11, 23:53
Thank you for your reply. I've nothing to add at this moment.

Mzungu mchagga
09-11-11, 00:01
Oh btw, it is even whole of Haplogroup I that has a faster progression in HIV-infection:

http://www.ncbi.nlm.nih.gov/pubmed/19169712

sparkey
09-11-11, 00:31
But, --> could someone please show the charts again of the percentages of paleolithic and younger autosomal DNA among European populations?

There's no such charts, because we can't "date" autosomal DNA in the same way that we can date Y-DNA, at least without a solid array of ancient samples to compare against.

However, it's a good working assumption that Paleolithic European Y-DNA was displaced more than Paleolithic European autosomal DNA, as evidenced by the fact that populations that share Y-DNA often do not cluster closely autosomally, and autosomal clusters usually approximate geography, indicating gradual movement.

How R1b replaced I and the Neolithic lineages so dramatically in Western Europe without taking the whole autosomal spectrum with it remains a good question, though. I think that there are multiple effects. Here is how I would rank them (just speculation):

1. Polygyny was more common than polyandry
2. Migrating men were more likely to have children with native women than migrating women were to have children with native men
3. Migrators were more likely to be men
4. R1b men tend to have higher sperm count than I men
5. R1b men tend to be more disease resistant than I men

So I think that disease resistance played a part, but is far removed from the main reason that R1b expanded so much. Most disease resistances are not influenced by Y-DNA, and if we're right that autosomal DNA has changed less from the Paleolithic than Y-DNA, only those influenced by Y-DNA would have really played a part.

zanipolo
09-11-11, 01:21
There's no such charts, because we can't "date" autosomal DNA in the same way that we can date Y-DNA, at least without a solid array of ancient samples to compare against.

However, it's a good working assumption that Paleolithic European Y-DNA was displaced more than Paleolithic European autosomal DNA, as evidenced by the fact that populations that share Y-DNA often do not cluster closely autosomally, and autosomal clusters usually approximate geography, indicating gradual movement.

How R1b replaced I and the Neolithic lineages so dramatically in Western Europe without taking the whole autosomal spectrum with it remains a good question, though. I think that there are multiple effects. Here is how I would rank them (just speculation):

1. Polygyny was more common than polyandry
2. Migrating men were more likely to have children with native women than migrating women were to have children with native men
3. Migrators were more likely to be men
4. R1b men tend to have higher sperm count than I men
5. R1b men tend to be more disease resistant than I men

So I think that disease resistance played a part, but is far removed from the main reason that R1b expanded so much. Most disease resistances are not influenced by Y-DNA, and if we're right that autosomal DNA has changed less from the Paleolithic than Y-DNA, only those influenced by Y-DNA would have really played a part.

I do not agree with your 4 and 5 , due to the fact that I migrated ( goths and est germans) for far longer historically up to the end of the roman empire, than what R1b did, then again we must not exclude R1a either.

Considering ( as per TRobb ) that italy, dalmatia and provence was I2a 5000BC, then we can reflect that your 4 and 5 might be correct, but what about the I1 and sardinia's and illyria's I HG !

I think 1, 2 and 3 are fine, but I also think that certain Hg's are superior in europe, like R1a

Mzungu mchagga
09-11-11, 11:48
There's no such charts, because we can't "date" autosomal DNA in the same way that we can date Y-DNA, at least without a solid array of ancient samples to compare against.

However, it's a good working assumption that Paleolithic European Y-DNA was displaced more than Paleolithic European autosomal DNA, as evidenced by the fact that populations that share Y-DNA often do not cluster closely autosomally, and autosomal clusters usually approximate geography, indicating gradual movement.

How R1b replaced I and the Neolithic lineages so dramatically in Western Europe without taking the whole autosomal spectrum with it remains a good question, though. I think that there are multiple effects. Here is how I would rank them (just speculation):

1. Polygyny was more common than polyandry
2. Migrating men were more likely to have children with native women than migrating women were to have children with native men
3. Migrators were more likely to be men
4. R1b men tend to have higher sperm count than I men
5. R1b men tend to be more disease resistant than I men

So I think that disease resistance played a part, but is far removed from the main reason that R1b expanded so much. Most disease resistances are not influenced by Y-DNA, and if we're right that autosomal DNA has changed less from the Paleolithic than Y-DNA, only those influenced by Y-DNA would have really played a part.

I share your speculations here!
Another idea that just came into my mind is that in fact there are heriditary "male diseases" due to the Y-chromosome, such as colour-blindness, hemophilia or baldness (if you count the last one as a disease). The dominant allele for no disease is on the X-chromosome, and woman seldomly get it as they already have two dominant alleles. The disease breaks out when a recessive allele comes into the game, through the Y-chromosome.
So if it would be true that only the male linages disapeared through a disease, it could have been because of the R1 people who had a lower prevalence of these diseases. If R1 came as warriors, they probably didn't suffer from colour-blindness or hemophilia anyway. (But from baldness perhaps...)

bertrand
09-11-11, 22:13
as discussed several times, it is more likely that it is the tolerence to lactose that gave R1b an advantage in conquering western europe. the could survive on milk and dairy products and were less dependant on the failure of crops.

Most other non european populations do not have this tolerance to lactose.