Studying monogenic hereditary disorders syndrome. A decline of probably pleiotropic and funthat manifest age-related phenotypes in cells, tissues, damental function of helicases in these disorders is, and the total organism would be helpful for clarifying therefore, implied to underlie not only the various agerelated phenotypes of the disorders but also the the mechanisms of aging. In this context, seven human disorders that manifest age-related phenotypes have pleiotropic and universal nature of ordinary aging.Consistent with this implication, studies of these seven been found to be caused by aberrations of five proteins disorders suggest that their various age-related phenowith seven helicase motifs conserved in most of the helicases. These disorders are xeroderma pigmentosum, types are caused by aberrations in multiple processes, Cockayne syndrome, trichothiodystrophy, Bloom syn-especially transcription. Furthermore, a few studies imply some association between aberration of the helidrome, Werner syndrome, X-linked h-thalassemia/mental retardation syndrome, and Juberg-Marsidi cases and phenotypes in ordinary aging.