G6PD and G6PD deficiency: Cut-off values of G6PD activity to determine G6PD deficiency differ for genetic background, for the G6PD gene is highly polymorphic with many variants, which could lead to decreased G6PD activity in erythrocytes or G6PD deficiency [20].To date, 270 mutations of the G6PD gene have been identified as pathogenic or likely pathogenic (https://www.ncbi.nlm.nih.gov/clinvar/?term=g6pd%5Bgene%5D&redir=gene), and over 200 pathogenic variants have been reported in China [21].