Your bloodline, lit up across the whole tree
Two thin threads of your DNA — the Y your fathers passed down, the mitochondria your mothers did — ride almost unchanged for thousands of years. So it never made sense that you had to re-enter a haplogroup on every relative. Now a single test illuminates the entire line it belongs to: name one man’s Y-DNA and it settles onto his father, his grandfather, his sons and his brothers, exactly where it must be. Tested people glow solid; the rest are quietly marked as inherited. One cousin’s kit can light up a whole branch.