What makes you think it is Sarmatian? My stepson would be thrilled to know that, if it is true.
I already posted my theory , but hier is another one for your stepson :
There is more reliable explanation of Sarmatian origins than that given by Herodotus( that they are descendants of Amazons and Scytians).Diodorus Siculus say that Scytians moved parts of Medians to they kingdom during they rule in Asia in VII century BC , and that Medians are called Sarmatians which means Solar Medes .And Kurds are descendants of Medians , thats why Sarmatians and Kurds both have I2a2 .
I2a2 is not a Slavic haplogroup , it is Saramatian . Slavs are mainly R1a and they are descendants of Scytians and nations they have conquered - Melanhleni , Neuri ,Androphage, ... I2a2 is strong in all regions where Sarmatians use to live : Ukraine ( coast of Black see -homeland of Sarmatians after they conquered Scytians , also there was some movement of Serbs in XVIII century to east Ukraine , and there is report by Byzantine patriarch Nichophorus that parts of Serbs and Croats have escaped on empty lands in today Poland - Krakow provincea Ukraine - Lviv aeria and Slovakia( Tatras )-Bielochorbatoi and Lendzans "those who live on empty land" , in today Ukraine and Belarus ( Red Ruthenia , Galicia ) - Boiki or Rusini named after Rascia one of Serbian states in Midle ages . It is interesting that higher level of I mth haplogroup in Europe is in Boiki 10% , and that haplogroup use to be 10% in Scandinavia during Midle ages but it has decreased. ), Moldavia and Romania ( also homeland of Sarmatians after they conquered Scytians , after colapse of Huns hier lives Ants whose names are Iranian- Sarmatian , also during the Hunic empire Saramatians use to live in Banat) , Sardinia ( Vandals mixed with Alans after move to Africa setled hier ,I think there is some I2 in Lybia to . Pliny say that Vandals were Saramatian nation) ,Serbia - Croatia -Bosnia -Macedonia-Montenegro (setled by Sarmatian tribes of Serbs-Serboi-Siraci and Croats -Harauati mentioned by Pliny the Elder like Sarmatian tribes ,Macedonia after XIII century), Bulgaria ( Bulgarians could partialy been Sarmatian , and there is emperor Constantine setling of 500.000 Sarmatians in Thrace , same is the case in Greece , also around Thesaloniki was first setling place of Serbs , Albania was part of Car Dušans empire , north Albania to river Liesus was in Serbian state Dioclitia-Duklja and some sources say Serbs and Croats use to hold to Apolonia - today city of Fier) , Hungary ( Magyars brought with them parts of Yazigs , in Hunic and Avar empire Sarmatians lived in Banat , and Turks chase population of Banat diper in to Hungary, there was also Serb and Croatian setling in Hungary), Slovenia( there used to live Venets probably cousins of Vandals , also great numbers of Croats escaped there infront of Turks ),north parts of Ossetians (North of Caucasus -Sarmatia untill II century AD there is strong I2a2 in some aerias of North Ossetia:: Digora 13% , Ardon 32% , Zil ga 0%, Zamankul 0% , Alagir 0% ,; there is also strong K2 Digora 0% , Ardon 7% , Zil ga 13% , Zamankul 21,7% , Alagir 8,3%( from Turks) . Strongest is the G 21-74% but that is the case in whole Caucasus ( race of goatbriders , populate all high mountins ) others are quite simillar to surounding nations - probably has something to do with custom to rape whole conquered village,haplogroup G is conected to goath breaders and is present on every big mountin like Caucasus , also high in Alpes-Austria , G could be Chimmerian- most of them finished on Caucasus after Lidians beated them ,Other higher than average densities of I occur in the Caucasus: Darginians of Dagestan 58% and Abkhazians 33%) , Czech republic ( Croats move on Balkans from there - Czech and Moravia , in X century there was a Croatian kingdom under Slavnik family , Serbs coming from Boiki - Bohemia , Bavaria and Lusitania-Lužica in Germany ) , Mordvinia republic in Russia ( in the area around Ryazansk moved groups of Roxolani, Volga Tatars has high I) ,Spain ( Alan and Vandal setlement , Katalonia, Aragon , Basque), France ( few Alanic kingdoms) , England ( 5000 Yazigian auxiliars after defeat against Marcus Aurelius- king Arthur) , Germany ( Serbs come on Balkans from river Elba-Laba , Sarland ). So all of I2a2 can be explained by Sarmatians moving - has nothing to do with Slavs .
Diferences Slavs - Serbs/Croats :Archeology shows that only in VI century there is proof of Slavic architecture on west Balkans ( one of it is village near Višegrad on Drina) , in later centuries there is no proof of Slavs on west Balkans- so called Archeological blank . If you look archeological sites of confirmed Slavs , like Kiev or village next to Višegrad , or Balaton in Hungary ,in Walachia in Romania ... you will se that they houses are partialy under ground made of wood and mud- so called zemunica , they villages are always on big rivers banks , they burn they deads and burry they ashes with no artefacts , thay use big curved one head axes and small trowing spears ,... Serbs and Croats findings are totaly diferent : they houses are made of stone and cowered with stone plates or bark of trees surounded with many smaller objects like stables , some of this objects are on slades - so they could be moved , they villages are always on mountains few miles from nearest river ( small or big ) ,Croats burry they deads without burning with a lot of artefacts , in round pits , in fetus position - like Yaziges in Banat during Avaric Khaganate , Serbs burn they deads , and puting ashes in specially builded litlle houses made of dried grass and woods , with lot of artefacts and food - similar to Ants burial customs in Moldavia ( it is believed Stećci -memorial stones in shape of house from Herzegovina mimic those burial houses), Serbs and Croats use twoheaded axes - like Sarmatians and long fighting spears .Slavic theory is based solely on languague , Sarmatians use to have more then one wife , while they use to fight , together with they Sarmatian wifes , Slavic wifes stayed at home briding childrens , so childrens had lurned Slavic languague , there is also other explanation that says Huns use Slavs like border guards ( it is proven Avars are ) , and small groups of Slavs transfered they languague like form of lingua Franca to conquered nations . It is proven that Slavic is very archaic - it has been spoken by small and closed group for over a millenium , it origins are proven to be around upper Pripyat.
There is also theory that I2a2 is paleolitic haplogroup who setled Balkans during last glacial maximum , that makes no sence because Greeks and Albanians -old popultions have less I2a2 then Serbs and Croats-newcomers , also Mesapi population of southern Italy has no I2a2 and they are Illyrians that crossed Adriatic see. What we do know with some amount of confidence is that current I2a-Din is only about 2500 years old, that it has expanded a lot, and that it has a center of diversity that seems to be north of the Balkans ,its spread showing it is grouped wich indicate there was resettling in near future , while older haplogroups - E1b1b1 , G2a and mythohondrial are more evenly spreaded all over Europe..And also if I2a2 is Peleolitic old population would make more then 80% of today Serbs which is imposible - Hunic and Avaro-Slavic invasions , litle ice age and plague that killed 30% of empire population during Justinian rule.
Kurds have K haplogroup ,and the Serbs to around 3% in some aerias up to 7% . Also Volga Tatari - inhabitants of Mordvinia republic in Russia where setled some Roxolans has 7,99% K and 18,4% I2a2 . Think that is K2 , which is present on Altay.
There is also some N in Serbs but not in neighboring nations , so they use to mix with some Finnic tribes.
I believe main Sarmatian gene was I2a2 , but they probably had lesser percent of R1a , G, J2, Q , and E1b1b , and only in Serbian case N and maybe some K2 ( aldo some researches hasnt find any K2 in Serbs ) .
Illyrians were probably E1b1b( strongest) , R1a , R1b ( some of mixing with Celts and some from Asia Minor ) , G , J, I2*B ,Q ,L and T .
Thracians were mainly J2 ( comed from Asia Minor ), E1b1, some R1a , R1b ( some of mixing with Celts and some from Asia Minor ) , G , I2*B ,Q ,L and T .
Dacians were Thracian tribe and similar to them , and Panonian to Illyrians.
I believe European Scythians mainly becamed Slavs - strong R1a , Slavs alos had some I2a2 , N , and E1b1
Hope he will be satisfy
