Finally I got downloaded the ancient La Braña genome. It is publicly available from the NCBI
sequence read archive. I refined it by GATK, a program reading genome
sequences and calling SNPs. A bit over 1
million SNPs were called, over 100k
overlapped with the 1M Illumina set used
by 23andme, but only 20 kSNP’s overlapped with my standard LD-pruned set. It is less than some other projects have been able to reach,
but still usable, although some amount of inaccuracy is seen in individual
results. The big view and locations of
populations on MDS-plots are still very
correct.
Playing around with PCA, which I have used earlier, I found it being poorly applicable in this
case and I moved to MDS. It was obvious
that the LaBrana1 sample being something different than any present-day population
didn’t share as much common SNP-level principal components with them as MDS can
retrieve using genetic distances.
Comparing to other online results shows some similarity and also
differences. What made me pondering was
the obvious Asian affinity of LaBrana1 shown on the Eurasian plot. This Asian affinity was shown around at the
same level with most eastern Russians, like most eastern samples from Vologda
and most eastern Mordvins. This is very
close what I have seen achieved by some other projects, but surprisingly
Lazaridis et al. didn’t show Asian
affinity for LaBrana1. Unfortunately he
didn’t inform us about the amount of SNPs used on his PCA-plot (or I didn't
find it), but the study tells that only a 10 kSNP overlapping set was obtained
for LaBrana1 and even less for some other ancient samples. But maybe I am wrong. Maybe I know more after testing other ancient WHG samples.
MDS plottings and IBS-statistics show closest similarity with Northern
European populations. My data lacks of
Basques, so I can’t say how close the LaBrana1 they might be. In general South Europeans are more distant
for LaBrana1 than North Europeans and Near Easteners are even more
distant. The closest population at
average IBS-level was Western/Southwestern Finns, but the difference to
Estonians and Lithuanians was quite small.
European MDS
Fulls size image available here
Eurasian MDS
Full size image available here
IBS-statistics for top ten individuals
Estonian 0.8101938
Lithuanian 0.8101357
FI0007 0.8099396
Belorussian 0.8098805
SC0001 0.8098763
Estonian 0.8098527
Lithuanian 0.8097566
FI0005 0.8096651
Lithuanian 0.809652
Russian 0.8094852
IBS average statistics including all population from my extended European
data set (East and North Asians excluded)
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