The results of multivariable logistic regression analyses showed that tetanus vaccine titer was significantly positively associated with the chances of becoming positive deviant (β = 0.182; 95% CI = 0.025–0.338; P = 0.03) after adjusting for sex, WAMI score, MPO, Neo, A1AT and length-for-age Z-score at birth. This evidence concerns the gene MPO and tetanus.