These were either protective (variation of iNOS Ser608Leu genotype in silicosis) or had deleterious effects (G>C mutation of NRAMP1 intron 4 in silicosis, combined NRAMP1 D543N G/G and INT4 G/C+C/C, polymorphic site of G/A substitutions at positions−308 of TNF-α and TNF-a-308 G/G and NRAMP1 INT4 G/C+C/C genotype in TB) (67, 68). This evidence concerns the gene NOS2 and silicosis.