To determine the role of individual IL-13 genotypes in conditioning susceptibility to SMA, a multivariate logistic regression analyses were carried out using the wild type in each variant as the reference group, while controlling for the confounding effects of age, gender, bacteremia, G6PD deficiency and sickle-cell trait [10,13,36-38] (Table 3). This evidence concerns the gene IL13 and G6PD deficiency.