Laboratory workup showed white blood cell (WBC) count of 15.9/mcL (4-10.6/mcL) with 90% neutrophils and hemoglobin (Hb) of 8.8 mg/dL (12-16 mg/dL) with a low mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) indicative of microcytic and hypochromic anemia, consistent with her previously diagnosed anemia of pregnancy. Here, GSTM1 is linked to anemia (phenotype).