IL17C and psoriasis: Furthermore, the putative four rSNPs involved in TNF, IL17C and IL17RA regulation that we found, could be validated in the clinic as companion diagnostics/pharmacogenetics assays for prescribed drugs for current psoriasis therapy as brodalumab, secukinumab, ixekizumab, infliximab, certolizumab, etanercept, golimumab and adalimumab.