1. The glutathione stability test of Beutler has been performed on blood samples from cases with past history of hemolytic anemia due to Vicia faba or sulfa drugs and some members of their families.
2. In all the affected cases the level of reduced glutathione (GSH) in erythrocytes fell below 30 mg./100 cc. RBC after two hours incubation with acetylphenylhydrazine (APH). Four out of 13 relatives examined showed the same results.
3. Out of 117 control cases only five showed similar results. All the five cases were Jews of Sefardic origin.
4. Indications have been found that by addition of glucose to the blood samples tested by the above method more clear-cut results could be obtained.
5. The decrease of the reduced glutathione level in the abnormal cells incubated with acetylphenylhydrazine could not be prevented by addition of glucose.
6. The decrease of reduced glutathione level in normal and abnormal cells incubated at 37 C. for 24 hours without acetylphenylhydrazine was prevented by addition of glucose. No such protective action of glucose on GSH in hemolysates had been found.