Genetic affinities among the historical provinces of Romania and Central Europe as revealed by an mtDNA analysis

Relu Cocoş,Mihai Constantinescu,Petru Cianga,Alina Martinescu,Florina Raicu,Claudia Bănescu,Montserrat Hervella,Roxana Popescu,Sorina Schipor

doi:10.1186/s12863-017-0487-5

Abstract

BackgroundAs a major crossroads between Asia and Europe, Romania has experienced continuous migration and invasion episodes. The precise routes may have been shaped by the topology of the territory and had diverse impacts on the genetic structure of mitochondrial DNA (mtDNA) in historical Romanian provinces. We studied 714 Romanians from all historical provinces, Wallachia, Dobrudja, Moldavia, and Transylvania, by analyzing the mtDNA control region and coding markers to encompass the complete landscape of mtDNA haplogroups.ResultsWe observed a homogenous distribution of the majority of haplogroups among the Romanian provinces and a clear association with the European populations. A principal component analysis and multidimensional scaling analysis supported the genetic similarity of the Wallachia, Moldavia, and Dobrudja groups with the Balkans, while the Transylvania population was closely related to Central European groups. These findings could be explained by the topology of the Romanian territory, where the Carpathian Arch played an important role in migration patterns. Signals of Asian maternal lineages were observed in all Romanian historical provinces, indicating gene flow along the migration routes through East Asia and Europe.ConclusionsOur current findings based on the mtDNA analysis of populations in historical provinces of Romania suggest similarity between populations in Transylvania and Central Europe, supported both by the observed clines in haplogroup frequencies for several European and Asian maternal lineages and MDS analyses.

Highlights

As a major crossroads between Asia and Europe, Romania has experienced continuous migration and invasion episodes
Based on multidimensional scaling (MDS) plots including the geographical neighbors or 41 populations, we found that Transylvania is more closely related to Central European populations than to the other Romanian provinces, which are more closely related to the Balkan populations (Fig. 3 and Additional file 6: Figure S1)
Geographical position and proximity to Central European populations, together with historical gene flow determined by the topology of Romania could explain these data

Summary

Introduction

As a major crossroads between Asia and Europe, Romania has experienced continuous migration and invasion episodes. The precise routes may have been shaped by the topology of the territory and had diverse impacts on the genetic structure of mitochondrial DNA (mtDNA) in historical Romanian provinces. We studied 714 Romanians from all historical provinces, Wallachia, Dobrudja, Moldavia, and Transylvania, by analyzing the mtDNA control region and coding markers to encompass the complete landscape of mtDNA haplogroups. As a segment of the Danube basin, this territory was a major crossroads between Asia and Southeastern, Central, and North Europe and one of the direct eastward routes linking to the North Pontic steppe. During the Iron Age, in the territory defined by the Danube Basin and Carpathian Arch, archaeological records and historical sources have revealed the presence of Indo-European populations close to Thracians who probably arrived during the second millennium BC named. The partial conquest of Dacia by Romans (1st to 2nd centuries AD), with the exception of current regions of Moldavia, northeastern Transylvania, and eastern Wallachia, was followed by a period of colonization by various groups from the Roman Empire (Italians, Illyrians, Thracians, Greeks, Celts, Germans, and Eastern or North Africans) who settled mostly in Transylvania [6]

Methods

Results

Discussion

Conclusion