The LW^b Blood Group as a Marker of Prehistoric Baltic Migrations and Admixture

Abstract

Archaeological findings and historical records indicate frequent migrations and exchange of genetic material between populations in the Baltic Sea area. However, there have so far been very few attempts to trace migrations in this area using genetic markers. We have studied the Baltic populations with respect to exceptional variations in the frequencies of the Landsteiner-Wiener (LW) blood group. The frequency of the uncommon LW^b gene was high in the Balts, around 6% among Latvians and Lithuanians, very low among the other western Europeans (0–0.1%) and apparently absent in Asiatic and African populations. From the Baltic region of peak frequency there was a regular decline of LW^b incidence (a descending cline) in the neighboring populations: 4.0% in the Estonians, 2.9% in the Finns, 2.2% in the Vologda Russians, and 2.0% in the Poles. Thus the distribution of LW^b suggests considerable and extensive Baltic admixture, especially in the north and northeast direction. In Southern Sweden with an LW^b frequency of 0.3%, the Baltic influence appeared slight, while in the population of the Swedish island Gotland in the middle of the Baltic Sea there was a significantly incrased LW^b frequency of 1.0% compared with that of Western European countries. The distinction of codominantly inherited LW antigenic forms, LW^a and LW^b (previously Ne^a), is known to be due to a single base substitution. Based on our population data, it is plausible that the expansion of this point mutation occurred only once during human history. Furthermore, our data indicate that the expansion of the LW^b mutation occurred in Balts and that LW^b can be considered a ‘Baltic tribal marker’, its presence in other populations being an indicator of the degree of Baltic genetic influence.

Y-Chromosomal Diversity Suggests that Baltic Males Share Common Finno-Ugric-Speaking Forefathers

“…This clearly seems to be the case in the Baltic region. Published data based on the careful analysis of both genetic [10,11,14] and craniological [5,6] material reveal marked similarities between the three Baltic populations, indicating that at least in this geographical territory the linguistic unit does not correspond to the genetic one.…”

“…A few reports concerning classical markers [8] and mtDNA diversity [9] exist, and they indicate that the closest genetic relatives of the Estonians are their Finno-Ugric-speaking neighbors, such as the Finns and the Karelians. Interestingly, recent studies based on both blood group antigens [10,11] and Y-chromosomal variation [12][13][14] suggest that the Indo-European-speaking part of the Baltic region is also genetically similar to the surrounding Finno-Ugric populations. Therefore, it seems that linguistic factors have had less influence on shaping the gene pool of the Baltic area.…”

Mitochondrial DNA Portrait of Latvians: Towards the Understanding of the Genetic Structure of Baltic‐Speaking Populations

“…TF * DCH1, PI, LW b ) among Latvians and Lithuanians have revealed genetic stratification of Baltic-speakers at the intrapopulation level Krumina et al 2001), as well as differences in the Baltic-speakers compared to other Indo-European and Finno-Ugricspeaking populations of the Baltic Sea region (Beckman et al 1998;Sistonen et al 1999). The analysis of one of the most common genetic diseases in Europeansphenylketonuria (PKU) -has revealed the predominance of a single mutation in the phenylalanine hydroxylase (PAH) gene, R408W of haplotype 2, in the Baltic states.…”

A New Baltic Population-Specific Human Genetic Marker in the PMCA4 Gene

“…One cluster, including Baltic countries, Poland, and western Russia, has been described, and there are other reports of variants arising from, or being specific to, this region, for example, the Landsteiner Wiener blood (LWb) group, and the PI Z allele in the SERPINA1 gene, among others [14,15] . The first indicator of Baltic genetic influence described was the rs77493670 variant in the ICAM4 gene, also known as the LWb allele [16] . The allelic frequency of this variant is 2-4% in countries surrounding the Baltic Sea, compared with 0.004% in other European populations (ExAC), allowing the conclusion that the rs77493670 mutation arose once in the Baltic population.…”

“…The allelic frequency of this variant is 2-4% in countries surrounding the Baltic Sea, compared with 0.004% in other European populations (ExAC), allowing the conclusion that the rs77493670 mutation arose once in the Baltic population. The subsequent expansion of this variant was regarded as a "Baltic tribe marker," representing population movements in this region [16] .…”