Our results provide clear biochemical and crystallographic evidence that the pathogenic R688Q, R735Q, and R735W AspH variants are catalytically less active than wt AspH while retaining the same fold as wt AspH (Table 1 and Fig. 4), supporting the proposal that the phenotypes associated with Traboulsi syndrome are due to a reduction in AspH oxygenase catalysis. The gene discussed is ASPH; the disease is facial dysmorphism-lens dislocation-anterior segment abnormalities-spontaneous filtering blebs syndrome.