Density of PDGFRα+ OPCs and QKI7+ OLs in the dorsal column. A, B, PDGFRα labeling in P13–P14 iBot+/+ (A) and iBottg/+ (B) dorsal column. C, PDGFRα+ cell density in iBottg/+ dorsal column (5.72 × 104 ± 2.05 × 103 cells/mm3) and control iBot+/+ dorsal column (4.84 × 104 ± 6.25 × 103 cells/mm3, Welch’s two sample t test, t(2.43) = −1.338, p =0.293, n = 3 animals for each genotype). D, E, QKI7 labeling in P13–P14 iBot+/+ (D) and iBottg/+ (E) dorsal column. F, QKI7+ cell density in iBottg/+ dorsal column (1.37 × 105 ± 1.45 × 104 cells/mm3) and control iBot+/+ dorsal column (2.34 × 105 ± 1.89 × 104 cells/mm3, Welch’s two sample t test, t(3.77) = 4.074, p = 0.017, n = 3 animals for each genotype).