The initial work was performed on African and European samples by a team of population geneticists, led by Laurent Excoffier.
On the basis of these, and similar findings by other geneticists, the hypothesis was elaborated by historical linguist George van Driem in 2010 that the teaching by a mother of her spouse's tongue to her children is a mechanism by which language has preferentially been spread over time.
Focusing on prehistoric language shift in already settled areas, examples worldwide[1] show that as little as 10–20% of prehistoric male immigration can (but need not) cause a language switch, indicating an elite imposition such as may have happened with the appearance of the first farmers or metalworkers in the Neolithic, Bronze and Iron Ages.
Instead, researchers had to rely on autosomal variation, starting with the first population genetic study using blood groups by Ludwik Hirszfeld in 1919.
[10] At the Indo-Pacific Prehistory Association conference in Taipei in 2002 he proposed that The next development was the discovery of specific Y-chromosomal markers linked to a language.
These language-specific Y-chromosomal markers create correlations such as those observed by Poloni et al. 1997, and furthermore allow the geographic extent, the time depth and the male immigration level underlying an unrecorded (prehistoric) language change to be determined.
The N1c haplogroup of the Y chromosome, distinguished by Tat-C deletion, is found at a high frequency throughout Uralic language communities, but is virtually missing in Hungarian males.