K2a is a subclade of the K2 haplogroup, which is part of the larger K mitochondrial DNA lineage. This haplogroup is primarily found in populations across Europe, Asia, and North America. It is believed to have originated around 20,000 years ago, during the last Ice Age, and has since diversified into various branches. The K2a subclade is particularly associated with Eastern Europe and Central Asia. Genetic studies suggest that individuals with K2a may have ancestral ties to ancient populations that migrated across these regions. This haplogroup is of interest to researchers studying human migration and genetic diversity.