Perhaps reflecting the low expression of GLDC in HFs relative to NPCs, qPCR for GLDC expression detected significantly increased GLDC levels in only one carrier HF (DL3363) compared with a non-carrier relative (DL6463) (Figure S1B). GLDC levels in hiPSCs (from both 9p24.1-carrier and isogenic non-carrier lines derived from DL3363 and DL5459) were significantly higher than in HFs (p = 0.0004 for DL3363 and p = 0.0002 for DL5459) (Figure 3G). While we observed a significant increase in GLDC expression in three 9p24.1-carrier hiPSCs from DL5459 relative to three isogenic non-carrier hiPSCs (p = 0.004), there was considerable variability in GLDC expression among DL3363 hiPSCs independent of carrier status (Figure 3G).
