Comparison of the native RRM2B protein structure and two mutant forms. (a) The structural model of the wild-type protein (Arg 41). (b) The structural model of the first mutated form (Pro 41). (c) The structural model of the second mutated form (Trp 41). Discontinuous cylinders represent hydrogen bonds; continuous lines represent hydrophobic bonds. Red residues are the main residues where the nsSNPs appeared; purple residues are those who that have a hydrogen bond with the main residue; green residues are those who that have a hydrophobic bond with the main residue; magenta residues mark the loss of a bond between an amino acid and the main residue in the variant form that existed in the wild-type form.