Maleylacetoacetate Isomerase Deficiency, also known as benign hypersuccinylacetonemia, is related to tyrosinemia, type i and tyrosinemia. An important gene associated with Maleylacetoacetate Isomerase Deficiency is GSTZ1 (Glutathione S-Transferase Zeta 1). Affiliated tissues include liver and t cells, and related phenotype is decreased liver function.