anglo-saxon burials and genetics in england

here’s a map (on the left) of anglo-saxon burial sites of the 5th to 7th centuries from “Anglo-Saxon immigration and ethnogenesis” compared to the distribution of the eastern, central, and southern english genetic cluster (red squares on map to right) from leslie et al. who found between 10-40% of the ancestry of those english to be anglo-saxon:

harcke - anglo-saxon burial sites 5th to 7th-8th centuries

that is all! (^_^)

previously: free cornwall now!

(note: comments do not require an email. anglo-saxon burial: lady and her cow.)

free cornwall now!

the long-awaited genetic ancestry mapping of the u.k. by the wellcome trust has finally been completed (hurrah!) — it’s very, very cool! — and it confirms what everyone has always known: the cornish are different! (~_^)

from nature news: UK mapped out by genetic ancestry“A map of the United Kingdom shows how individuals cluster based on their genetics, with a striking relationship to the geography of the country”:

u.k. genetic ancestry mapping

as you can see, all the calls for cornish independence have been justified! the good folks of cornwall are their own little genetic subpopulation, even distinct from their neighbors in devon (as they’ve known all along). so there! =P

to sum up the major findings:

– the welsh appear to be genetically quite different from the rest of the subpopulations in britain, and so the authors reckon they are the most like the earliest hunter-gatherers who migrated to britain at the end of the last ice age.

– the analyses suggest that there was a substantial migration across the channel after the original post-ice-age settlers but before roman times. white british people today have thirty percent (30%) of their dna ancestry from germanic populations, and people in southern and central england share 40% of their dna with the french (again, this relatedness is pre-norman). there’s also substantial relatedness to danes and belgians due to these early migrations. these migrations had little impact in wales.

– there wasn’t a single “celtic” genetic group in britain before the later invasions of the anglo-saxons, etc. the scots, northern irish, welsh, and cornish are some of the most different from each other genetically. the cornish (free cornwall!) are more similar genetically to other english groups than they are to the welsh, for instance.

– the english in eastern, central, and southern england (all those red squares) are pretty much one, relatively homogeneous, genetic group having significant genetic contributions — between 10-40% of their total ancestry — from the anglo-saxons. this strongly indicates that the invading anglo-saxons intermarried with the existing populations and did not replace them 100%.

– fantastically, the danish vikings (of the danelaw of the ninth century) do NOT appear to have left much dna behind at all. their numbers must’ve been small and/or most of them left (or were killed) at some point.

– the cornish (free cornwall!) and devonians are distinct genetic subgroups, and the division between the two groups lies pretty much at the boundaries between the two counties.

– the subpopulation of west yorkshire look like they’re the descendants of the people of elmet (the last of the brittonic kingdoms to hold out against the anglo-saxons)!

– the cumbrians and the northumbrians are distinct from each other, the people of west yorkshire, and the rest of the english.

– yes, the english-speaking population of pembrokeshire is genetically distinct from the rest of the welsh.

– the orkney islanders are the most genetically distinct of all the subgroups having 25% norwegian dna. again, though, the viking invaders mated with the locals and didn’t replace them 100%.

dál riata is apparent on the map there, as are the lowland scots and border reievers contributions to the ulster scots population.

from the telegraph:

“Geneticist Professor Sir Walter Bodmer of Oxford University said: ‘What it shows is the extraordinary stability of the British population. Britain hasn’t changed much since 600AD.

“‘When we plotted the genetics on a map we got this fantastic parallel between areas and genetic similarity.

“‘It was an extraordinary result, one which was much more than I expected. We see areas like Devon and Cornwall where the difference lies directly on the boundary.’

“Professor Mark Robinson, of Oxford University’s department of archaeology added: ‘The genetic make-up we see is really one of perhaps 1400 years ago.'”
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for the purposes of this blog, one of the most interesting things is that lack of a danish viking genetic legacy in england. one of the things we’ve been puzzling about here is where on earth the puritans came from, and one of the ideas that has been bandied about has been that perhaps they were the descendants of the danes, since the danish vikings controlled east anglia and that’s where the purtians were from. that idea doesn’t seem to hold water anymore.

(there’s something else in the paper that may or may not, kinda-sorta be of interest regarding the general topic of this blog, but i’m going to address that in a separate post.)

speaking of the puritans and albion’s seed (and american nations), jayman’s already tweeted this!:

(^_^) so there you go.
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i think that’s everything for now. there’s a LOT to take in from this research. i look forward to what razib and greg cochran will have to say on the paper.

for now, for more info, have a look at these!:

UK mapped out by genetic ancestry: “Finest-scale DNA survey of any country reveals historical migrations.”
– the original research article (behind a stupid paywall): The fine-scale genetic structure of the British population. the supplementary information file [pdf] looks like it’s a good read.
Britons still live in Anglo-Saxon tribal kingdoms, Oxford University finds: “A new genetic map of Britain shows that there has been little movement between areas of Britain which were former tribal kingoms in Anglo-Saxon England.”
Genetic study reveals 30% of white British DNA has German ancestry: “Analysis over 20 years reveals heavy Anglo-Saxon influence, with French and Danish DNA coming from earlier migrations than the Normans or Vikings.”
Study Reveals Genetic Path of Modern Britons: “Researchers found 17 clusters, based on genetic relatedness, in the modern British population.”
Scientists discover genetic “border” between Devon and Cornwall
– from dienekes: British origins (Leslie et al. 2015)

(note: comments do not require an email. free cornwall now!)

chinese cleaners smarter than western professionals

here’s the latest re. the most recent pisa test results (various news outlets are reporting that the below also applies to the u.s. and canada – check google news for pisa+oecd):

“China’s poorest beat our best pupils”

“Children of factory workers and cleaners in Far East achieve better exam results than offspring of British lawyers and doctors, says OECD.

“British schoolchildren are lagging so far behind their peers in the Far East that even pupils from wealthy backgrounds are now performing worse in exams than the poorest students in China, an international study shows.

“The children of factory workers and cleaners in parts of the Far East are more than a year ahead of the offspring of British doctors and lawyers, according to a report by the Organisation for Economic Co-operation and Development….

“As part of the study, children were asked to name their parents’ occupation to determine its effect on pupil performance. Across the world, children whose parents work in professional careers generally outperform those in elementary jobs such as caterers, cleaners, factory workers and labourers.

“The study, involving more than 500,000 pupils worldwide, found children of elementary workers in many Far Eastern nations outperformed the sons and daughters of professional British children.

“The children of UK professionals scored an average of 526 points in maths. But this was overshadowed by an average score of 656 registered by the children of professionals in Shanghai-China and 569 among children of the country’s elementary workers. The children of parents in unskilled jobs in the UK scored an average of 461, the equivalent of two and a half years behind.

“Elementary workers’ children in Hong Kong (542), South Korea (538) and Singapore (534), also outperformed more affluent British peers. In Japan, Vietnam, Liechtenstein, Japan and China-Taipei, relatively poor children were only marginally behind the wealthiest British pupils.

“The report said: ‘In the United States and the United Kingdom, where professionals are among the highest-paid in the world, students whose parents work as professionals do not perform as well in mathematics as children of professionals in other countries — nor do they perform as we as the children in Shanghai-China and Singapore whose parents work in manual occupations….'”

no idea if any of these results were broken down by race, ethnicity, etc.

and a related story from a while back:

“Report: Chinese Third-Graders Falling Behind U.S. High School Students in Math, Science”

“According to an alarming new report published Wednesday by the International Association for the Evaluation of Educational Achievement, third-graders in China are beginning to lag behind U.S. high school students in math and science.

“The study, based on exam scores from thousands of students in 63 participating countries, confirmed that in mathematical and scientific literacy, American students from the ages of 14 to 18 have now actually pulled slightly ahead of their 8-year-old Chinese counterparts.

“‘This is certainly a wake-up call for China,’ said Dr. Michael Fornasier, an IEA senior fellow and coauthor of the report. ‘The test results unfortunately indicate that education standards in China have slipped to the extent that pre-teens are struggling to rank among even the average American high school student….'”

(~_^)

(note: comments do not require an email. or an average pisa score above ca. 450.)

inbreeding and cognitive ability among whites in the u.k.

via dienekes via jayman:

Genome-wide estimates of inbreeding in unrelated individuals and their association with cognitive ability

“INTRODUCTION

“Research on consanguineous marriages, and other forms of inbreeding, has long shown a reduction in cognitive abilities in the offspring of such unions. The presumed mechanism is that detrimental recessive mutations are more likely to be identical by descent in the offspring of such unions and so have a greater chance of being expressed. To date, research on the relationship between inbreeding and cognitive ability has largely been restricted to recent inbreeding events as determined by pedigree…. It has been suggested that intellectual disability is under negative selection, and that recent deleterious mutations have an important role in the underlying aetiology. The wealth of molecular genetic data currently available allows estimates of inbreeding on a genome-wide level and to examine the effects of long-term ancestral levels of inbreeding. Such an association with inbreeding, as measured by runs of homozygous polymorphisms (ROH), has previously been identified with several behavioural traits, such as schizophreniz, Parkinson’s disease and personality measures, as well as non-behavioural traits such as height.

“The relationship between inbreeding on a population level and cognitive ability is particularly interesting due to assortative mating, non-random mating, which is greater for cognitive ability than for other behavioural traits, as well as physical traits such as height and weight. Positive assortative mating has been reported for cognitive ability, particularly for verbal traits, with spousal correlations generally around 0.5. Assortative mating should lead to greater genetic similarity between mates at causal loci for cognitive ability and to a lesser extent across the genome, which in turn reduces heterozygosity at these local. In other words, in contrast to the genome-wide reduction of heterozygosity caused by inbreeding, the reduction of heterozygosity due to assortative mating for a trait is limited to loci associated with the trait…. Another difference between inbreeding and assortative mating is that the effects of inbreeding are expected to be negative, lowering cognitive ability, whereas the effects of assortative mating affect the high, as well as the low end of the ability distribution, thus increasing genetic bariance, that is, when high-ability parents mate assortatively, their children are more likely to be homozygous for variants for high ability, just as offspring of low-ability parents are more likely to be homozygous for variants for low ability….

“MATERIALS AND METHODS

“Participants

“The Twins Early Development Study (TEDS) recruited over 11 000 families of twins born within England and Wales between 1994 and 1996…. In this analysis, individuals were excluded if they reported severe current medical problems, as well as children who had suffered severe problems at birth or whose mothers had suffered severe problems during pregnancy. Twins whose zygosity was unknown or uncertain or whose first language was not English were also excluded. Finally, analysis was restricted to twins whose parents reported their ethnicity as ‘white’….

“Cognitive measures

“Verbal and non-verbal tests were administered using web-based testing. The verbal tests consisted the Similarities subtest and the Vocabulary subtests from the Wechsler Intelligence Scale for children (WISC-III-UK). The non-verbal tests were the Picture Completion subtest from the WISC-III-UK and Conceptual Grouping from the McCarthy Scales of Children’s Abilities. A general score was derived from the test battery as the standardized sum of the standardized subtest scores, which correlates 0.99 with a score derived as the first principle component of the test battery score.

“Runs of homozygosity

“FROH was defined as the percentage of an individual’s genome consisted of runs of homozygosity (ROH)…. [O]nly ROH with a minimum of 65 consecutive SNPs covering 2.3Mb were used when calculating the total proportion of the genome covered by ROH. In addition, the required minimum density in a ROH was set at 200kb per SNP, and the maximum gap between two consecutive homozygous SNPs was set at 500kb….

“RESULTS

“Table 1 includes descriptive statistics for FROH and the three measures of cognitive ability (general, verbal, and non-verbal). FROH is slightly positively skewed, as it represents the total percentage of the genome that includes runs of homozygosity (ROH). The average percentage of genome covered by ROH was 0.7% (95% CI 0.65-0.72%). Verbal and non-verbal abilities correlate 0.49; because general cognitive ability is the sum of the standardized verbal and non-verbal subtests, they correlate much more highly with general ability (0.87 and 0.86, respectively).

inbreeding and iq - table 01

“Table 2 presents the results of the linear regression analyses. No significant regression was found between FROH and the cognitive measures after correction for multiple testing, although the association with non-verbal cognitive ability was nominally significant (P=0.03). Although this association was not statistically significant, it is noteworthy that every regression in Table 2 is *positive*, indicating that increased homozygosity tends to be associated with *higher* cognitive scores across different measures of cognitive ability (general, verbal and non-verbal).

inbreeding and iq - table 02

“Our analysis identified 87 loci where ROH overlapped in 10 or more individuals. For these overlapping regions we tested for association with each of the cognitive measures and again showed no significant associations after correction for multiple testing (P-values of less than 5.7 x 10-4). A sign test of the direction of effect across all ROH showed a disproportionately large number of *positive* associations, indicating that ROH are associated with higher cognitive ability (P=0.002). The sign test was non-significant for verbal ability but highly significant for non-verbal ability (P<10-6). The sign test for non-verbal ability alone remained significant after correcting for an individual’s genome-wide FROH score (P<10-6).

“As explained earlier, positive assortative mating can also lead to genome-wide homozygosity for trait-specific loci, and, unlike inbreeding, assortative mating can affect the high as well as the low end of the ability distribution. One possible explanation for the trend suggesting a positive correlation between homozygosity and cognitive scores in our data is that positive assortative mating on intelligence might be greater for high cognitive ability individuals….

“DISCUSSION

“Our results show that within a representative UK population sample there was a weak nominally significant association between burden of autosomal runs of homozygosity and higher non-verbal cognitive ability. This nominal association with *increased* cognitive ability is counterintuitive when compared with the results from more extreme inbreeding based on pedigree information. A potential explanation for this direction of effect is that individuals with higher cognitive ability might show greater positive assortative mating, which would lead to increased homozygosity at loci for higher cognitive ability in their offspring. However, in a separate sample we showed that greater positive assortative mating was not associated with higher cognitive ability. While these findings seem to provide clear evidence against this hypothesis, it is possible that the genome-wide genetic finding reflect historical mating habits that no longer exist today. It should also be noted that there was a reduction in the standard deviations for spousal correlations in the increased cognitive ability groups by an average of 6% compared with the decreased cognitive ability group (see Table 3), which could reflect less genetic variability in the high ability couples or a ceiling effect on the cognitive tests. This lesser phenotypic variability at the high ability end would have a small effect in reducing the spouse correlations and potentially confound our analysis….

“Overall, these results highlight the importance of understanding mating habits, such as inbreeding and assortative mating, when investigating the genetic architecture of complex traits such as cognitive ability. The results certainly suggest that there is no large effect of FROH on reduced cognitive ability, the expected direction of effect. The nominally significant associations found in this study may even suggest that in the case of non-verbal cognitive ability, beneficial associations with homozygosity at specific loci might outweigh the negative effects of genome-wide inbreeding and that the relationship between inbreeding and cognitive ability may be more complicated than previously thought.
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so, although obviously Further Research is RequiredTM, these researchers have concluded that both the absence of reduced cognitive ability and the slight increase in cognitive ability which they found in individuals who had runs of homozygosity (roh) in their genomes (evidence of matings between genetically similar individuals) were probably NOT due to assortative mating (i.e. smart people mating with smart people).

furthermore, they suggest that the inbreeding-causes-reduced-cognitive-ability meme is incorrect — or at least that the situation is more complicated than the idea that it’s the accumulation of recent deleterious mutations which haven’t been selected away that is the (whole) problem. in fact, a little inbreeding seems to have a positive effect on some cognitive abilities!

i’ve suggested a couple of times one way in which inbreeding might result in a low average iq in a population, and that is if the inbreeding leads to clannish, altruistic behaviors between extended family members which then result in the deleterious mutations NOT being weeded out.

one real world example i’ve offered is how life works in egyptian villages and how the more successful and affluent (and, presumably, more intelligent) members of a clan are obliged to help out their less successful and poorer (and, presumably, less intelligent) clan members. so, apart from mentally retarded individuals not reproducing, where is the negative selection for deleterious mutations here? there is none. or it’s a lot weaker than in more individualistic societies (like gregory clarks’ medieval england) where it’s more every man for himself — in clannish societies, deleterious mutations might be able to hang around for a long time, riding on the coattails of those with fewer deleterious mutations.

(note: comments do not require an email. i’m my own grandpa! [no, I’M not! it’s just the song.])