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Maciamo
10-09-18, 10:30
Here is a long article published by the researcher himself in The Conversation about the presumed origins of cystic fibrosis, the most common genetic disease among people of European descent.

Discovering the ancient origin of cystic fibrosis, the most common genetic disease in Caucasians (http://theconversation.com/discovering-the-ancient-origin-of-cystic-fibrosis-the-most-common-genetic-disease-in-caucasians-100499)

"Imagine the thrill of discovery when more than 10 years of research on the origin of a common genetic disease, cystic fibrosis (CF), results in tracing it to a group of distinct but mysterious Europeans who lived about 5,000 years ago.

[...]

I decided that we might be able to discover the origin of CF by analyzing the DNA in the teeth of Iron Age people buried between 700-100 B.C. in cemeteries throughout Europe.

Using this strategy, I teamed up with archaeologists and anthropologists such as Maria Teschler-Nicola at the Natural History Museum in Vienna, who provided access to 32 skeletons buried around 350 B.C. near Vienna. Geneticists in France collected DNA from the ancient molars and analyzed the DNA. To our surprise, we discovered the presence of the F508del mutation in DNA from three of 32 skeletons.

[...]

To find the origin of CF in modern patients, we knew we needed to learn more about the signature mutation – F508del – in people who are carriers or have the disease.

This tiny mutation causes loss of one amino acid out of the 1,480 amino acid chain and changes the shape of a protein on the surface of the cell that moves chloride in and out of the cell. When this protein is mutated, people carrying two copies of it – one from the mother and one from the father – are plagued with thick sticky mucus in their lungs, pancreas and other organs. The mucus in their lungs allows bacteria to thrive, destroying the tissue and eventually causing the lungs to fail. In the pancreas, the thick secretions prevent the gland from delivering the enzymes the body needs to digest food.

So why would such a harmful mutation continue to be transmitted from generation to generation?

[...]

We obtained DNA samples from 190 CF patients bearing F508del and their parents residing in geographically distinct European populations from Ireland to Greece plus a Germany-derived population in the U.S. We then identified a collection of genetic markers – essentially sequences of DNA – within the CF gene and flanking locations on the chromosome. By identifying when these mutations emerged in the populations we studied, we were able to estimate the age of the most recent common ancestor.

Next, by rigorous computer analyses, we estimated the age of the CF mutation in each population residing in the various countries.

We then determined that the age of the oldest common ancestor is between 4,600 and 4,725 years and arose in southwestern Europe, probably in settlements along the Atlantic Ocean and perhaps in the region of France or Portugal. We believe that the mutation spread quickly from there to Britain and Ireland, and then later to central and southeastern European populations such as Greece, where F508del was introduced only about 1,000 years ago.

[...]

Thus, our newly published data suggest that the F508del mutation arose in the early Bronze Age and spread from west to southeast Europe during ancient migrations.

Moreover, taking the archaeological record into account, our results allow us to introduce a novel concept by suggesting that a population known as the Bell Beaker folk were the probable migrating population responsible for the early dissemination of F508del in prehistoric Europe. They appeared at the transition from the Late Neolithic period, around 4000 B.C., to the Early Bronze Age during the third millennium B.C. somewhere in Western Europe. They were distinguished by their ceramic beakers, pioneering copper and bronze metallurgy north of the Alps and great mobility. All studies, in fact, show that they were into heavy migration, traveling all over Western Europe.

Over approximately 1,000 years, a network of small families and/or elite tribes spread their culture from west to east into regions that correspond closely to the present-day European Union, where the highest incidence of CF is found. Their migrations are linked to the advent of Western and Central European metallurgy, as they manufactured and traded metal goods, especially weapons, while traveling over long distances. It is also speculated that their travels were motivated by establishing marriage networks. Most relevant to our study is evidence that they migrated in a direction and over a time period that fit well with our results. Recent genomic data suggest that both migration and cultural transmission played a major role in diffusion of the “Beaker Complex” and led to a “profound demographic transformation” of Britain and elsewhere after 2400 B.C.

Over approximately 1,000 years, a network of small families and/or elite tribes spread their culture from west to east into regions that correspond closely to the present-day European Union, where the highest incidence of CF is found (https://www.cysticfibrosisjournal.com/article/S1569-1993(08)00034-9/fulltext). Their migrations are linked to the advent of Western and Central European metallurgy, as they manufactured and traded metal goods, especially weapons, while traveling over long distances. It is also speculated that their travels were motivated by establishing marriage networks. Most relevant to our study is evidence that they migrated in a direction and over a time period that fit well with our results. Recent genomic data suggest that both migration and cultural transmission played a major role in diffusion of the “Beaker Complex” and led to a “profound demographic transformation” of Britain and elsewhere after 2400 B.C.

Determining when F508del was first introduced in Europe and discovering where it arose should provide new insights about the high prevalence of carriers – and whether the mutation confers an evolutionary advantage. For instance, Bronze Age Europeans, while migrating extensively, were apparently spared from exposure to endemic infectious diseases or epidemics; thus, protection from an infectious disease, as in the sickle cell mutation, through this genetic mutation seems unlikely."


While the study is interesting, the author, Philip Farrell, unfortunately had to deal with one of the most complex ancient cultures: the Bell Beaker culture (or phenomenon). Had he checked Eupedia and the latest DNA tests of the Reich's lab, he would have realised that the so-called "Beaker folk" were not a single ethnic group and that the Beaker people from Iberia were genetically distinct from those of Central Europe, Belgium, Britain and Ireland. Therefore I don't see how the mutation for cystic fibrosis could have been spread from Iberia to other parts of Europe. It is more likely that the diffusion occurred the other way round. In fact, if we look at the present prevalence of CF it peaks in Ireland (2.98 per 10,000), followed by Britain (1.37), Belgium (1.03), Italy (0.872), Austria (0.839), Germany (0.829), the Netherlands (0.781), Denmark (0.761), France (0.750), then Slovakia (0.627), Estonia (0.618), and only after that Spain (0.546). Portugal is far behind at 0.271, one of the lowest prevalence in Europe (after Lithuania and Latvia) and half that of Greece (0.521).

The high prevalence in modern Ireland and in the ancient samples from Iron-Age Austria (La Tène culture) suggests a stronger association with Celtic people. Its high prevalence in Italy, but also Germany, the Netherlands and Denmark indicates that it could have been the Italo-Celto-Germanic R1b-P312 branch that originally spread cystic fibrosis. The fast of expansion of these Indo-European people from Central to Western Europe coincides exactly with the age of cystic fibrosis in this study (2600-2700 BCE). Spain and Portugal would have lower frequencies of CF because R1b tribes arrived later in Iberia and in a more diluted form after many centuries of intermingling with local people in France.

Angela
10-09-18, 20:15
Here is a long article published by the researcher himself in The Conversation about the presumed origins of cystic fibrosis, the most common genetic disease among people of European descent.
Discovering the ancient origin of cystic fibrosis, the most common genetic disease in Caucasians (http://theconversation.com/discovering-the-ancient-origin-of-cystic-fibrosis-the-most-common-genetic-disease-in-caucasians-100499)
"Imagine the thrill of discovery when more than 10 years of research on the origin of a common genetic disease, cystic fibrosis (CF), results in tracing it to a group of distinct but mysterious Europeans who lived about 5,000 years ago.
[...]
I decided that we might be able to discover the origin of CF by analyzing the DNA in the teeth of Iron Age people buried between 700-100 B.C. in cemeteries throughout Europe.
Using this strategy, I teamed up with archaeologists and anthropologists such as Maria Teschler-Nicola at the Natural History Museum in Vienna, who provided access to 32 skeletons buried around 350 B.C. near Vienna. Geneticists in France collected DNA from the ancient molars and analyzed the DNA. To our surprise, we discovered the presence of the F508del mutation in DNA from three of 32 skeletons.
[...]
To find the origin of CF in modern patients, we knew we needed to learn more about the signature mutation – F508del – in people who are carriers or have the disease.
This tiny mutation causes loss of one amino acid out of the 1,480 amino acid chain and changes the shape of a protein on the surface of the cell that moves chloride in and out of the cell. When this protein is mutated, people carrying two copies of it – one from the mother and one from the father – are plagued with thick sticky mucus in their lungs, pancreas and other organs. The mucus in their lungs allows bacteria to thrive, destroying the tissue and eventually causing the lungs to fail. In the pancreas, the thick secretions prevent the gland from delivering the enzymes the body needs to digest food.
So why would such a harmful mutation continue to be transmitted from generation to generation?
[...]
We obtained DNA samples from 190 CF patients bearing F508del and their parents residing in geographically distinct European populations from Ireland to Greece plus a Germany-derived population in the U.S. We then identified a collection of genetic markers – essentially sequences of DNA – within the CF gene and flanking locations on the chromosome. By identifying when these mutations emerged in the populations we studied, we were able to estimate the age of the most recent common ancestor.
Next, by rigorous computer analyses, we estimated the age of the CF mutation in each population residing in the various countries.
We then determined that the age of the oldest common ancestor is between 4,600 and 4,725 years and arose in southwestern Europe, probably in settlements along the Atlantic Ocean and perhaps in the region of France or Portugal. We believe that the mutation spread quickly from there to Britain and Ireland, and then later to central and southeastern European populations such as Greece, where F508del was introduced only about 1,000 years ago.
[...]
Thus, our newly published data suggest that the F508del mutation arose in the early Bronze Age and spread from west to southeast Europe during ancient migrations.
Moreover, taking the archaeological record into account, our results allow us to introduce a novel concept by suggesting that a population known as the Bell Beaker folk were the probable migrating population responsible for the early dissemination of F508del in prehistoric Europe. They appeared at the transition from the Late Neolithic period, around 4000 B.C., to the Early Bronze Age during the third millennium B.C. somewhere in Western Europe. They were distinguished by their ceramic beakers, pioneering copper and bronze metallurgy north of the Alps and great mobility. All studies, in fact, show that they were into heavy migration, traveling all over Western Europe.
Over approximately 1,000 years, a network of small families and/or elite tribes spread their culture from west to east into regions that correspond closely to the present-day European Union, where the highest incidence of CF is found. Their migrations are linked to the advent of Western and Central European metallurgy, as they manufactured and traded metal goods, especially weapons, while traveling over long distances. It is also speculated that their travels were motivated by establishing marriage networks. Most relevant to our study is evidence that they migrated in a direction and over a time period that fit well with our results. Recent genomic data suggest that both migration and cultural transmission played a major role in diffusion of the “Beaker Complex” and led to a “profound demographic transformation” of Britain and elsewhere after 2400 B.C.
Over approximately 1,000 years, a network of small families and/or elite tribes spread their culture from west to east into regions that correspond closely to the present-day European Union, where the highest incidence of CF is found (https://www.cysticfibrosisjournal.com/article/S1569-1993(08)00034-9/fulltext). Their migrations are linked to the advent of Western and Central European metallurgy, as they manufactured and traded metal goods, especially weapons, while traveling over long distances. It is also speculated that their travels were motivated by establishing marriage networks. Most relevant to our study is evidence that they migrated in a direction and over a time period that fit well with our results. Recent genomic data suggest that both migration and cultural transmission played a major role in diffusion of the “Beaker Complex” and led to a “profound demographic transformation” of Britain and elsewhere after 2400 B.C.
Determining when F508del was first introduced in Europe and discovering where it arose should provide new insights about the high prevalence of carriers – and whether the mutation confers an evolutionary advantage. For instance, Bronze Age Europeans, while migrating extensively, were apparently spared from exposure to endemic infectious diseases or epidemics; thus, protection from an infectious disease, as in the sickle cell mutation, through this genetic mutation seems unlikely."
While the study is interesting, the author, Philip Farrell, unfortunately had to deal with one of the most complex ancient cultures: the Bell Beaker culture (or phenomenon). Had he checked Eupedia and the latest DNA tests of the Reich's lab, he would have realised that the so-called "Beaker folk" were not a single ethnic group and that the Beaker people from Iberia were genetically distinct from those of Central Europe, Belgium, Britain and Ireland. Therefore I don't see how the mutation for cystic fibrosis could have been spread from Iberia to other parts of Europe. It is more likely that the diffusion occurred the other way round. In fact, if we look at the present prevalence of CF it peaks in Ireland (2.98 per 10,000), followed by Britain (1.37), Belgium (1.03), Italy (0.872), Austria (0.839), Germany (0.829), the Netherlands (0.781), Denmark (0.761), France (0.750), then Slovakia (0.627), Estonia (0.618), and only after that Spain (0.546). Portugal is far behind at 0.271, one of the lowest prevalence in Europe (after Lithuania and Latvia) and half that of Greece (0.521).
The high prevalence in modern Ireland and in the ancient samples from Iron-Age Austria (La Tène culture) suggests a stronger association with Celtic people. Its high prevalence in Italy, but also Germany, the Netherlands and Denmark indicates that it could have been the Italo-Celto-Germanic R1b-P312 branch that originally spread cystic fibrosis. The fast of expansion of these Indo-European people from Central to Western Europe coincides exactly with the age of cystic fibrosis in this study (2600-2700 BCE). Spain and Portugal would have lower frequencies of CF because R1b tribes arrived later in Iberia and in a more diluted form after many centuries of intermingling with local people in France.

Fascinating. Thanks, Maciamo.

I agree with you that this is somehow tied to "Celtic/Gallic" populations. I wonder, however, if it could have mutated in a group of Central European Bell Beaker folk who arrived in Spain and then spread from there?

I've seen this in real life in two families of Irish origin. One tiny mutation causing such havoc and horror. At the time I'm speaking of, even with modern medications, suctioning the mucous from these poor children every day, they still died young and after torture for both them and their parents.

berun
12-09-18, 22:09
Better a blurred vision than to see a detail? R1b without steppe, L51 areas, BB culture geographic origin, BB with less steppe in Central Europe (=expansion of a more EEF pop), and now CF which is taken almost like a Y-DNA clade.

The case for expansion of CF was already assigned to Celts by the same author a year ago:


Initially, we are seeking direct evidence demonstrating that CF was associated with prehistoric Europeans, namely the Celts who emerged as a distinct culture after the Bronze Age. The Celtic tribes as a warrior society with master metal workers then flourished during the Iron Age and, after large scale migrations,10 occupied the regions of Europe where CF is most common.2, 4, 8 The availability of relatively large populations of Iron Age skeletons provided an opportunity to determine if F508del was present in their DNA.