Of these, two C-terminal OGR1 variants were shown to be a risk factor for chemotherapy-induced peripheral neuropathy, possibly due to alterations in arrestin binding and subsequent aberrant activation of OGR1 in so-called PEP1 neurons, a subgroup of C-fibre nociceptors that express a specific subset of proteins and play a key role in pain sensation [31]. Here, GPR68 is linked to peripheral neuropathy.