Obtained results of molecular genetics testing of workers' groups exposed to dust show the elimination of carriers of defective variants in the CFTR gene among workers exposed to dust. We can establish a fact that in spite of law frequency of detected major mutations of the CFTR gene in explored selections they have big importance as individual factors in the stage of preliminary medical examinations in terms of prediction of possible occupational development risk and progression of productionally mediated visceropathies and diseases, as well as a conscious choice of occupation by an individual.