 Further work examining the behavioural response of two other transgenic mouse strains; one lacking Nav1.7 in all DRG neurons and the other lacking Nav1.7 in all DRG neurons as well as all sympathetic neurons, has revealed distinct sets of modality specific peripheral neurons.Therefore, Nav1.7 expressed in Nav1.8 positive DRG neurons is critical for normal responses to acute mechanical and inflammatory pain assays.Whilst Nav1.7 expressed in Nav1.8 negative DRG neurons is critical for normal responses to acute thermal pain assays.