Cell division plays a critical role in the normal growth, maintenance and repair of human tissue. Telomeres are repeated sequences of DNA at the ends of each chromosome, and are key genetic elements involved with the regulation of cell division. Telomeres shorten every time a cell divides, and once telomeres reach a critically short length, the cell either dies by apoptosis or stops dividing and senesces.

Telomerase is a naturally occurring enzyme that maintains telomeres and prevents them from shortening during cell division. Telomerase consists of at least two essential components: an RNA template, which binds to the telomere, and a catalytic subunit with reverse transcriptase activity, which adds the specific DNA sequence to the chromosome ends each time a cell divides.