Patrilinear in a sentence as an adjective

If you go 30 generations back, you might have a billion ancestors, but only 30 patrilinear ones.

The article uses somewhat confusing language, but I think this is about the most recent common patrilinear ancestor; now older than what was assumed before.

We have technology to measure patrilinear ancestry through the Y chromosome, and matrilinear ancestry through the mitochondrial DNA.

Patrilinear definitions

adjective

based on or tracing descent through the male line; "a patrilineal society"

See also: patrilineal