Mesolithic Scandinavia: Early Postglacial Migration Routes & High-Latitude Adaptation

[Jovialis]

http://journals.plos.org/plosbiology...l.pbio.2003703

Population genomics of Mesolithic Scandinavia: Investigating early postglacial migration routes and high-latitude adaptation


Abstract


Scandinavia was one of the last geographic areas in Europe to become habitable for humans after the Last Glacial Maximum (LGM). However, the routes and genetic composition of these postglacial migrants remain unclear. We sequenced the genomes, up to 57× coverage, of seven hunter-gatherers excavated across Scandinavia and dated from 9,500–6,000 years before present (BP). Surprisingly, among the Scandinavian Mesolithic individuals, the genetic data display an east–west genetic gradient that opposes the pattern seen in other parts of Mesolithic Europe. Our results suggest two different early postglacial migrations into Scandinavia: initially from the south, and later, from the northeast. The latter followed the ice-free Norwegian north Atlantic coast, along which novel and advanced pressure-blade stone-tool techniques may have spread. These two groups met and mixed in Scandinavia, creating a genetically diverse population, which shows patterns of genetic adaptation to high latitude environments. These potential adaptations include high frequencies of low pigmentation variants and a gene region associated with physical performance, which shows strong continuity into modern-day northern Europeans.

[Jovialis]

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[Jovialis]

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[Angela]

Expected, I think, in terms of uniparental markers:
" All the western and northern Scandinavian individuals and one eastern Scandinavian carried U5a1 mt haplotypes, whereas the remaining eastern Scandinavians carried U4a haplotypes (Table 1, S5 Text). These individuals represent the oldest U5a1 and U4 lineages detected so far. The Y chromosomal haplotype was determined for three of the four males, all carried I2 haplotypes, which were common in pre-Neolithic Europe."

Also expected as far as I'm concerned that the high frequencies for fair skin coupled with blue eyes in Scandinavia was the result of selection because of climate.

More interesting are the adaptation traits to these latitudes, some of which seem to have remained in modern populations. I have to read it more thoroughly, but they seem related to a whole host of things.

[alexfritz]

suggests a very northern entry of EHG into scandinavia (north>south) pos via a reindeer-trek over lappland/northern finland that must have been the route, Steigen seems to be the youngest SHG of the study-group SHGs and the most northern, and still displays a very high EHG admix, akin to the earlier Hum SHGs further south whereas the SF SHGs on Gotland (roughly contemporary to Hum SHGs) are much more WHG admixed;

[Promenade]

"Thus, many genetic variants found in Mesolithic individuals have not been carried over to modern-day groups. Among the novel variants in SF12, four (all heterozygous) are predicted to affect the function of protein coding genes [33] (S3 Text). The “heat shock protein” HSPA2 in SF12 carries an unknown mutation that changes the amino acid histidine to tyrosine at a protein–protein interaction site, which likely disrupts the function of the protein (S3 Text). Defects in HSPA2 are known to drastically reduce fertility in males [34]. It will be interesting to see how common such variants were among Mesolithic groups as more genome sequence data become available"

Well that might help explain why all the I2 disappeared. If I1 did come from the funnelbeaker culture into Scandinavia it would explain how they became dominant so quickly

[bicicleur]

this is not new
this study has been published last year and discussed here in eupedia

[Jovialis]

^^

https://www.eupedia.com/forum/thread...ic-Scandinavia

You're right, it was titled differently at the time, and was a pre-print and not peer-reviewed yet:

"Genomics of Mesolithic Scandinavia reveal colonization routes and high-latitude adaptation"

It said it was published January 9, 2018, and is currently being reported in all of the science websites as of yesterday. Thus I assumed it was brand-new, and didn't see anything posted about it as of that time. Sorry for that bicicleur, in the future, I'll consider the received time, and search to see if a pre-print had been posted and discussed.

[bicicleur]

I saw the date, 9 januari.
I have read it at the time, I don't know if there are alterations or new elements in this new publication.
Maybe I'll read it later.

[Jovialis]

I saw the date, 9 januari.
I have read it at the time, I don't know if there are alterations or new elements in this new publication.
Maybe I'll read it later.

From a glance, It looks like they've omitted the part about the 3D reconstruction of the Mesolithic woman. I didn't read anything about it in new version.

[werner]

The postglacial settlement came from Ahrensburger Culture, later Hamburger Culture.
The Ahrensburger Type - Cultures was in western slavic/baltic countrys (include Latvia) and north european from Drenthe to Narva the same population (north alpine Hunter and Gatherer and pannonian-hungarian Hunter and Gatherer but with different culture names).
The Initial Point for settlement was the Vulcanism by End of Glacial/Holocene Start in the Eifel Region. These has crashed with a big flood (result of a broken Lava Damm) formed a new Rhine-Maas-Schelde Delta and broke the last bridge by Dover-Cal. As result of this event came a new settlement from Eifel-north germany population about Jutland to southwest scandinavia and to the same time to southeast england.
The second population came from Western Ural-Wolga-upper Dniepr region about Karelia to Scandinavia around the same time. I think this all is a result by lifted Scandinavian Ice shild, but i think they have not a mutation of HSPA2.
This mutation is younger.

[MOESAN]

"Thus, many genetic variants found in Mesolithic individuals have not been carried over to modern-day groups. Among the novel variants in SF12, four (all heterozygous) are predicted to affect the function of protein coding genes [33] (S3 Text). The “heat shock protein” HSPA2 in SF12 carries an unknown mutation that changes the amino acid histidine to tyrosine at a protein–protein interaction site, which likely disrupts the function of the protein (S3 Text). Defects in HSPA2 are known to drastically reduce fertility in males [34]. It will be interesting to see how common such variants were among Mesolithic groups as more genome sequence data become available"

Well that might help explain why all the I2 disappeared. If I1 did come from the funnelbeaker culture into Scandinavia it would explain how they became dominant so quickly

aside: if I had to bet for Funnelbeaker I would bet rather a lot of Y-I2a2 based upon what we have among GAC and Western Megalithic pops, rather less Y-I1. But who knows at this stage?

[I1a3_Young]

aside: if I had to bet for Funnelbeaker I would bet rather a lot of Y-I2a2 based upon what we have among GAC and Western Megalithic pops, rather less Y-I1. But who knows at this stage?

I would bet that as well. I1 seems to have been a very small group until 4600 ybp. Would be nice to test some Funnel Beaker though, even if I2.