TLR7 and systemic lupus erythematosus: Of note, TLR7 gene, which is of high importance for DN2 activation,13 is a chromosome X-linked gene, thus explaining (at least in part) the sex-bias that accompanies SLE immunopathogenesis.55,56 As far as genetic burden is concerned, it is well known that ethnicity -among other factors- is linked to the severity of SLE manifestations.57 A better understanding of the differences among the various ethnic groups could probably enable better management of SLE patients.