Indeed, our model was able to identify pathological P50 values in our “positive control” groups, even in the presence of abnormal Hb: most P50 values were lower than normal in the HbCO group, with a median P50 of 22.5 mmHg [21.6–23.8]; on the contrary most P50 values were higher than normal in the SCD group, with a median P50 of 30 mmHg [26.9–31.9] in untreated patients and 28.2 mmHg [27–31.2] in the ones receiving hydroxycarbamide. The gene discussed is GSTM1; the disease is Schnyder corneal dystrophy.