Y chromosome sequencing data suggest dual paths of haplogroup N1a1 into Finland

[Tautalus]

Abstract

The paternally inherited Y chromosome is highly informative of genetic ancestry, therefore making it useful in studies of population history. In Finland, two Y-chromosomal haplogroups reveal the major substructure of the population: N1a1 enriched in the northeast and I1a in the southwest, suggested to reflect eastern and western ancestry contributions to the population. Yet, beyond these major Y-chromosomal lineages, the distribution of finer-scale Y-chromosomal variation has not been assessed in Finland. Here, we provide the most comprehensive Y-chromosomal study among the Finns to date, exploiting sequences for 1802 geographically mapped Finnish Y chromosomes from the FINRISK project. We assessed the distribution of common Y-chromosomal haplogroups (frequency ≥1%) throughout 19 Finnish regions and compared the autosomal genetic backgrounds of the Y-chromosomal haplogroups. With such high-resolution data, we were able to find previously unreported sublineages and resolve phylogenetic relationships within haplogroups N1a1 (64%), I1a (25%), R1a (4.3%), and R1b (4.8%). We further find novel geographical enrichment patterns among these Y-chromosomal haplogroups, most notably observed for haplogroup N1a1 dividing into two lineages with differing distributions. While sublineage N-Z1934 (42%) followed a northeastern enrichment pattern observed for all N1a1 carriers in general, sublineage N-VL29 (22%) displayed an enrichment in the southwest. Further, the carriers of N-VL29 showed a higher proportion of southwestern autosomal ancestry compared to carriers of N-Z1934. Collectively, these results point to distinct demographics within haplogroup N1a1, possibly induced by two distinct arrival routes into Finland. Overall, our study suggests a more complex genetic population history for Finns than previously proposed.​

Y chromosome sequencing data suggest dual paths of haplogroup N1a1 into Finland - European Journal of Human Genetics

The paternally inherited Y chromosome is highly informative of genetic ancestry, therefore making it useful in studies of population history. In Finland, two Y-chromosomal haplogroups reveal the major substructure of the population: N1a1 enriched in the northeast and I1a in the southwest...

www.nature.com

Y-chromosomal variation in Finland

 

[Jaska]

Good, although this result was already generally known. The regional frequency maps are good, although I would have hoped for maps of many more subhaplogroups at least to the time frame of Mid Iron Age.

Frequency maps of Y-chromosomal haplogroups in Finland - out of all samples

Y-chromosomal regional enrichment maps for all haplogroups with at least 1% frequency in Finland out of all samples. A star (*) within the map and gray color in the forest plot indicates the frequency is inferred by combining samples from geographically closest regions due to low coverage of...

zenodo.org