Fine mapping of susceptibility to RSV bronchiolitis at this locus [21] suggested that additional risk variants in the region mapped to a region excluding the AFM gene (which codes for an albumin-like protein expressed in the liver) but including the novel gene RASSF6, a member of the Ras superfamily of small GTPases that can mediate bacterial entry by controlling changes in the actin cytoskeleton [28-30]. Here, RASSF6 is linked to respiratory syncytial virus bronchiolitis.