Patients with the less common IFNλ3 minor allele SNPs (TG or GG compared with major allele genotype TT) have increased seroconversion after influenza vaccination and enhanced protection specifically against two antigens, with alterations seen in both activated influenza-specific T cells and human leukocyte antigen (HLA)-expressing B cells (43). This evidence concerns the gene IFNL3 and influenza.