Figure 3.

Telomerase function and DNA damage response system. Telomerase is the ribonucleoprotein responsible for the preservation of telomeres. Under normal condition, telomerases are able to counterbalance the physiological nucleo-tide loss of the chromosomal telomeric portion, and therefore prevents chromosome end-to-end fusions and rearrange-ments. In parallel, DNA damage response manages lesions and mutations occurring in non-telomeric portions of the DNA double strands. Primary telomeropathies are directly related to telomerase dysfunction, whereas secondary telom-eropathies are related to the misfunction of the DNA damage response proteins. For details, see text section on telomer-opathies. FA, Fanconi anemia.