Biology – Replication and division of nuclei and cells | e-Consult

If a somatic cell has a mutation preventing telomerase production, the telomeres will continue to shorten with each cell division. This will have significant consequences for the cell's lifespan and function.

Likely effects:

• Reduced Cell Lifespan: The cell will eventually reach a critical telomere length where it triggers cellular senescence or apoptosis. The cell's replicative potential will be severely limited.
• Increased Senescence: The cell will likely enter senescence sooner than normal, contributing to tissue dysfunction and age-related decline.
• Increased Genomic Instability: As telomeres shorten, the cell becomes more susceptible to chromosomal abnormalities, including fusions and rearrangements. This increases the risk of mutations and further cellular dysfunction.
• Impaired Function: The cell's ability to perform its specific function may be impaired due to the accumulation of DNA damage and the activation of cellular stress responses.

Justification: Telomeres protect chromosomes from degradation. Without telomerase to maintain telomere length, the 'end replication problem' will lead to progressive telomere shortening. This shortening triggers cellular senescence and apoptosis, ultimately limiting the cell's lifespan and impairing its function. The mutation effectively removes the mechanism that counteracts the natural shortening of telomeres during DNA replication, leading to a cascade of negative consequences.