Although the electrophoretic mobility of Hb Rothschild frequently overlaps with the Hb D region on hemoglobin electrophoresis, it differs fundamentally from classical Hb D variants in both molecular mechanism and functional impact: Hb Rothschild decreases hemoglobin–oxygen affinity rather than altering structural stability or causing clinically significant anemia. Here, GSTM1 is linked to anemia.