New venues of research to understand its role in autoimmunity have opened by murine models with loss of function and upregulated TLR7 activity like the yaa model (a chromosomal translocation that contains the murine TLR7 gene) [57] and most importantly the characterization of a human TLR7 gain-of-function mutation in a lupus patient and in a mouse strain with the identical mutation [58]. The gene discussed is TLR7; the disease is systemic lupus erythematosus.