Middle Don Catacomb MBA replaced by genetically distinct Srubnaya LBA. Scythians split into four genetic clusters close to modern Europeans. IA Scythians derive 90-95% ancestry from steppe BA populations. Eastern Siberian/Asian ancestry minor at under 10% in most Scythians. Early Scy_South lack steppe BA ancestry but have over 50% southern sources like Anatolian. No direct genetic continuity from Middle Don BA to IA Scythians. Classical Scythians share more alleles with Western/Baltic BA than Iranian/Central Asian. Scythians genetically distinct from Sarmatians despite cultural overlap. Middle Don Scythians form patrilineal R1a clan with high endogamy and consanguinity. Elite Scythians Dev1 and DS93 closely related within clan. Scythians predicted mostly brown/blond hair, blue eyes, matching Herodotus descriptions. Scythians lack lactose persistence and alcohol intolerance variants. HFE variant for hemochromatosis in Scythians fits meat diet and bronze skin. ALDOB p.Ala150Pro fructose intolerance mutation originated in Scythians around 1st millennium BCE. Scythian genetic legacy strongest in modern Eastern Baltic and Northwestern Russian populations.