Interestingly, a study by Jendryczko et al. [6] shows that in children infested with G. lamblia occurs a decrease of zinc absorption in the gastrointestinal tract which causes zinc deficiencies in those children; when compared with non-infected children, mean concentrations of serum zinc carriers, total protein, albumin fraction, transferrin and picolinic acid—a zinc absorption factor in the gastrointestinal tract—were not differing between both studied groups of children. The gene discussed is TF; the disease is Zinc deficiency.