In situ hybridization patterns of selected genes: In situ hybridization on cryostat section of P0 Wild type (A, D, G, J, M, P), P0 TrkA mutant (B, E, H, K, N, Q) and adult (C, F, I, L, O, R) with DIG-labelled probes for TrkA (A, B, C); Scn10a (D, E, F); CGRP (G, H, I); Dok4 (J, K, L); Crip2 (M, N, O) and Grik1/GluR5 (P, Q, R). Arrows in L and O indicate unlabelled cells. TrkA mutant DRGs are encircled in B, E, H, K, N and Q. Data show that Dok4 was expressed in the majority of neurons, scattered negative cells was observed, arrows in L. Crip2 was widely expressed, although substantial numbers of negative cells were noted, arrows in O. Grik1/GluR5 was expressed in sub-population of neurons and was completely absent from TrkA mutant DRG. Scale bar 50 μm.