Here we present 115 whole mitogenomes and 92 Y-chromosomal Short Tandem Repeat (STR)
and Single Nucleotide Polymorphism (SNP) profiles from a Hungarian ethnic group, the
Székelys (in Romanian: Secuii, in German: Sekler), living in southeast Transylvania
(Romania). The Székelys can be traced back to the 12th century in the region, and
numerous scientific theories exist as to their origin. We carefully selected sample
providers that had local ancestors inhabiting small villages in the area of Odorheiu
Secuiesc/Székelyudvarhely in Romania. The results of our research and the reported
data signify a qualitative leap compared to previous studies since it presents the
first complete mitochondrial DNA sequences and Y-chromosomal profiles of 23 STRs from
the region. We evaluated the results with population genetic and phylogenetic methods
in the context of the modern and ancient populations that are either geographically
or historically related to the Székelys. Our results demonstrate a predominantly local
uniparental make-up of the population that also indicates limited admixture with neighboring
populations. Phylogenetic analyses confirmed the presumed eastern origin of certain
maternal (A, C, D) and paternal (Q, R1a) lineages, and, in some cases, they could
also be linked to ancient DNA data from the Migration Period (5th–9th centuries AD)
and Hungarian Conquest Period (10th century AD) populations.
