Scientists have discovered the secret behind a very rare blood type called AnWj. They figured out which gene is responsible for it. This discovery will help doctors better understand and care for people with this rare blood type.

Most major blood groups were identified early in the 20th century. Many discovered since, like the Er blood system first described by researchers in 2022, only impact a small number of people. This is also the case for the new blood group. "The work was difficult because the genetic cases are very rare," explained Tilley.