Experiment/figure number	Statistics
Figure 5B: Limb size for stage 46 DMSO or SU5402 treatments	Unpaired one-tailed Student’s t-test • n = 5 (DMSO), n = 6 (SU5402) • Mean (DMSO) = 0.1614, Mean (SU5402) = 0.072 • SD (DMSO) = 0.015582, SD (SU5402) = 0.0177539 • SEM (DMSO) = 0.006969, SEM (SU5402) = 0.007248 • p-value<0.0001 • T = −8.775 • 95% confidence interval = −0.06636 to −0.11244
Figure 5E: qRT-PCR data for DMSO or SU5402 treated stage 46 limbs	Unpaired two-tailed Student’s t-test • n = 3 (DMSO), n = 3 (SU5402) • Mean (DMSO) = 1.09 (Etv1), 1 (Etv4), 0.97 (Shh), 0.85 (Ptch1), 1.1 (Gremlin1) • Mean (SU5402) = 0.28 (Etv1), 0.4 (Etv4), 0.37 (Shh), 1.25 (Ptch1), 0.47 (Gremlin1) • SD (DMSO) = 0.055 (Etv1), 0.1 (Etv4), 0.06 (Shh), 0.18 (Ptch1), 0.07 (Gremlin1) • SD (SU5402) = 0.05 (Etv1),. 04 (Etv4), 0.12 (Shh), 0.22 (Ptch1), 0.24 (Gremlin1) • SEM (DMSO) = 0.03 (Etv1),. 06 (Etv4), 0.03 (Shh), 0.11 (Ptch1), 0.04 (Gremlin1) • SEM (SU5402) = 0.03 (Etv1),. 02 (Etv4), 0.08 (Shh), 0.13 (Ptch1), 0.14 (Gremlin1) • p-value=<0.0001 (Etv1), 0.0006 (Etv4), 0.0022 (Shh), 0.07 (Ptch1), 0.014 (Gremlin1) • T = −19.13 (Etv1), −9.79 (Etv4), −6.95 (Shh), 2.44 (Ptch1), −4.14 (Gremlin1) • 95% confidence interval = −0.7 to −0.91 (Etv1),−0.43 to −0.77 (Etv4), −0.36 to −0.83 (Shh), 0.9 to −0.05 (Ptch1), −0.2 to −1 (Gremlin1)
Figure 5I: Cell proliferation in DMSO or SU5402 treated stage 46 limbs	One-way ANOVA (Kruskal-Wallis tests) • n = 3 each for DMSO and SU5402 • Median: DMSO = 29.15, SU5402 = 4.75 • p-value=0.0495
Figure 5—figure supplement 1A and C: Limb size for stage 45 DMSO or SU5402 and ethanol or cyclopamine treatments	Unpaired one-tailed Student’s t-test • n = 15 (DMSO), n = 15 (SU5402) • Mean (DMSO) = 0.082, Mean (SU5402) = 0.074 • SD (DMSO) = 0.016, SD (SU5402) = 0.012 • SEM (DMSO) = 0.004, SEM (SU5402) = 0.003 • p-value=0.0514 • T = −1.68637 • 95% confidence interval = −0.019 to 0.002 • n = 6 (ethanol), n = 6 (cyclopamine) • Mean (ethanol) = 0.071, Mean (cyclopamine) = 0.063 • SD (ethanol) = 0.012, SD (cyclopamine) = 0.006 • SEM (ethanol) = 0.002, SEM (cyclopamine) = 0.005 • p-value=0.909 • T = 1.43 • 95% confidence interval = −0.004 to 0.02
Figure 5—figure supplement 1B and D: Snout to tail-tip length for DMSO or SU5402 and ethanol or cyclopamine treatments	Unpaired one-tailed Student’s t-test • n = 5 (DMSO), n = 6 (SU5402) • Mean (DMSO) = 10.92, Mean (SU5402) = 10.29 • SD (DMSO) = 0.2, SD (SU5402) = 0.25 • SEM (DMSO) = 0.088, SEM (SU5402) = 0.104 • p-value<0.0007 • T = −4.5 • 95% confidence interval = −0.316 to −0.950 • n = 6 (ethanol), n = 6 (cyclopamine) • Mean (ethanol) = 10.5, Mean (cyclopamine) = 9.98 • SD (ethanol) = 0.15, SD (cyclopamine) = 0.3 • SEM (ethanol) = 0.06, SEM (cyclopamine) = 0.121 • p-value<0.0016 • T = 3.87 • 95% confidence interval = 0.82 to 0.222
Figure 6B: Limb size for stage 46 ethanol or cyclopamine treatments	Unpaired one-tailed Student’s t-test • n = 6 (ethanol), n = 6 (cyclopamine) • Mean (ethanol) = 0.16, Mean (cyclopamine) = 0.095 • SD (ethanol) = 0.008, SD (cyclopamine) = 0.016 • SEM (ethanol) = 0.003, SEM (cyclopamine) = 0.006 • p-value<0.0001 • T = 8.36 • 95% confidence interval = 0.08 to 0.045
Figure 6C: qRT-PCR data for ethanol or cyclopamine treated stage 46 limbs	Unpaired one-tailed Student’s t-test • n = 3 (ethanol), n = 3 (cyclopamine) • Mean (ethanol) = 1.12 (Ptch1), 0.94 (Gremlin1), 1.12 (Fgf8) • Mean (cyclopamine) = 0.7 (Ptch1), 0.39 (Gremlin1), 0.22 (Fgf8) • SD (ethanol) = 0.145 (Ptch1), 0.12 (Gremlin1), 0.14 (Fgf8) • SD (cyclopamine) = 0.00.04 (Ptch1), 0.1 (Gremlin1), 0.03 (Fgf8) • SEM (ethanol) = 0.08 (Ptch1), 0.07 (Gremlin1), 0.08 (Fgf8) • SEM (cyclopamine) = 0.02 (Ptch1), 0.06 (Gremlin1), 0.02 (Fgf8) • p-value=0.0039 (Ptch1), 0.002 (Gremlin1), 0.0002 (Fgf8) • T = 4.9 (Ptch1), 5.97 (Gremlin1), 11.21 (Fgf8) • 95% confidence interval = 0.66 to 0.19 (Ptch1), 0.8 to 0.3 (Gremlin1), 1.1 to 0.68 (Fgf8)
Figure 6G: Cell proliferation in ethanol or cyclopmaine treated stage 46 limbs	One-way ANOVA (Kruskal-Wallis tests) • n = 3 each for ethanol and cyclopamine • Median: ethanol = 30.06, cyclopamine = 13.9, • p-value=0.0495