The function of Ensembl gene identifier ENSG00000134184 (GSTM1, glutathione S-transferase mu 1) is as follows. Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. Involved in the formation of glutathione conjugates of both prostaglandin A2 (PGA2) and prostaglandin J2 (PGJ2) (PubMed:9084911). Participates in the formation of novel hepoxilin regioisomers (PubMed:21046276). {ECO:0000269|PubMed:16548513, ECO:0000269|PubMed:21046276, ECO:0000269|PubMed:9084911}.