**2. Genetic factors and normal aging**

It seems that the aging process is determined by both changes in the levels of biochemical factors as well as multiple genetic variants. It is believed that normal aging is associated with genes such as *SIRT1, AKT1* and *CDKN1A*, while longevity with e.g. *FOXO3A* and *CETP*. On the other hand, weakness of cognitive function during senescence may be modified by poly-T variants of *TOMM40* and *APOE* alleles via influencing the level of apolipoprotein E [4, 5].

A detailed description of the molecular factors in aging process is provided in the chapter on genetic factors associated with longevity. According to the authors, longevity may be a complex

polygenic trait influenced by many genetic changes. In addition, longevity phenomena are influenced by both epigenetic and environmental factors.

The aging process may be traced based on experimental models using candidate genes enabling early detection of aging before the emergence of typical phenotypes. Such experimental model may be plants because they allow for the examination of complex mechanisms of molecular changes during aging.

In the last years, publications point to the involvement of many molecular factors in the development of normal aging. However, we still did not prevent the pathological changes in the aging organism in the form of cardiologic, neurological, or oncological diseases.
