Another group of studies substantiated by Anand et al. (2004) as part of the Randomized Etanercept North American Strategy to Study Antagonism of Cytokines (RENAISSANCE) trial, found the presence of anemia (Hb ≤12.0 g/dL) in 12% of the 69 participants [37]. This evidence concerns the gene GSTM1 and anemia (phenotype).