SULT2A1 and disorder of glycogen metabolism: Recently, a meta-analysis involving 8,720 GSD cases and 55,152 controls identified four additional risk factors, including the Transmembrane 4 L six family member 4, TM4SF4 gene (rs9843304), the Sulfotransferase family 2 A member 1 SULT2A1 gene (rs2547231), the glucokinase regulator, GCKR gene (rs1260326) and the cytochrome P450 family 7 subfamily A member 1, CYP7A1 gene (rs6471717)15.