New research suggests that many people are prone to suffer badly from the flu because of their genetic make - up . About one in 400 people carries a variant of a gene called IFITM3 that makes them more likely to suffer serious illness when they are infected with the flu virus. About one in 400 people has the genetic variant IFITM3 which causes the flu to be a more serious problem and testing people for the virus can help cure them .
New research suggests that many people are prone to suffer badly from the flu because of their genetic make - up . About one in 400 people has the genetic variant IFITM3 which causes the flu to be a more serious problem and testing people for the virus can help cure them .