My opinion will be based on "Kurgan Hypothesis"
The Kurgan hypothesis is one of the proposals about early Indo-European origins, which postulates that the people of an archaeological "Kurgan culture" in the Pontic steppe were the most likely speakers of the Proto-Indo-European language. The term is derived from "Kurgan", a Turkic loanword in Russian for a tumulus or burial mound. The Kurgan model is the most widely accepted scenario of Indo-European origins.
Proto-Indo-European Autosomal DNA
+ noticeable amount (0-5%) of Mongoloid (Most Likely Siberian)
The rise of archaeogenetic evidence which uses genetic analysis to trace migration patterns also added new elements to the origins puzzle. In terms of genetics, the subclade R1a1a (R-M17 or R-M198) is the most commonly associated with Indo-European speakers. Most discussions purportedly of R1a origins are actually about the origins of the dominant R1a1a (R-M17 or R-M198) subclade. Data so far collected indicates that there are two widely separated areas of high frequency, one in Eastern Europe, around Poland and the Russian core, and the other in South Asia, around North India. The historical and prehistoric possible reasons for this are the subject of on-going discussion and attention amongst population geneticists and genetic genealogists, and are considered to be of potential interest to linguists and archaeologists also.
Out of 10 human male remains assigned to the Andronovo horizon from the Krasnoyarsk region, 9 possessed the R1a Y-chromosome haplogroup and one C-M130 haplogroup (xC3).
Proto-Indo-European people were mostly (90%) R1a.
Genetically Most Proto-Indo-European influenced IE-speaking people in Europe
Ukrainian Autosomal Dna
Caucasus (West_Asian) 13.7
It seems to me that present-day Ukrainians have at least 40-50% PIE admixture (by looking at their North_European+West_Asian+Siberian combination and 40% R1a in Ukraine).
Genetically Least Proto-Indo-European influenced IE-speaking peoples in Europe
Albanians and some other Southern European peoples.
R1a in Albania; 0-5%
R1a in Italy; 0-3%
R1a in Iberia; 0-3%