"The newsletter indicates (in descending order) in
Italy 20% of 156 G samples......
Spain 15% of 56 G samples.....
Netherlands 15% of 20 G samples......
Switzerland 8% of 51 G samples.....
Iran 6% of 34 G samples....
Poland 4% of 75 G samples......
France 4% of 46 G samples......
Ireland 3% of 29 G samples.......
India 3% of 18 G samples." Wiki
"vast majority of Northwest Europeans are G2a3" Maciamo - 15% does not sound like vast majority in the Netherlands. It's pretty clear that G2a3 is rare every where, and G2a1 is most common in Europe. Turkey has the highest percentage of G2a3 people.
"In addition, a possible connection to the Alans was of interest because certain areas of Europe have a distribution of haplogroup G incorresponding to those to which large numbers of Alans and other Sarmatians migrated." Wiki
G2a has the best connection to a possible Marrivigean Sarmation connection, IMO. Georgia has similar population of G2a3 as other European countries, and it's in the right place for Sarmatian and Alan influence.