A telomere is a region of repetitive DNA at the end of a chromosome, which protects the end of the chromosome from deterioration. Its name is derived from the Greek nouns telos (τἐλος) "end" and merοs (μέρος, root: μερ-) "part".
Russian theorist Alexei Olovnikov was the first to recognize (1971) the problem of how chromosomes could replicate right to the tip, as such was impossible with replication in a 5' to 3' direction. To solve this and to accommodate Leonard Hayflick's idea of limited somatic cell division, Olovnikov suggested that DNA sequences would be lost in every replicative phase until they reached a critical level, at which point cell division would stop.
Telomeres and telomerase: biological and clinical importance ...
(15) developed an assay for testing telomerase activity in cell extracts. Based on identification of telomerase mechanisms and properties, the telomere ...
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