DAO and cerebellar ataxia: When DAAO-TGTie2 mice are fed D-alanine, we saw no ataxia whatsoever, and we found that there was no expression of the Tie2-driven transgene in DRG neurons (Supplementary Fig. 7) despite robust transgene expression of the transgene in mesenteric (Supplementary Fig. 6b, c) and cardiac (Supplementary Fig. 6e) blood vessels.