Hayflick Limit

The Hayflick limit (or Hayflick phenomenon) is the number of times a normal human cell population will divide until cell division stops. Empirical evidence shows that the telomeres associated with each cell's DNA will get slightly shorter with each new cell division until they shorten to a critical length.

The Hayflick limit was discovered by Leonard Hayflick in 1961, at the Wistar Institute in Philadelphia. Hayflick demonstrated that a population of normal human fetal cells in a cell culture will divide between 40 and 60 times. The population will then enter a senescence phase, which refutes the contention by Nobel laureate Alexis Carrel that normal cells are immortal. Each mitosis slightly shortens each of the telomeres on the DNA of the cells. Telomere shortening in humans eventually makes cell division impossible, and this aging of the cell population appears to correlate with the overall physical aging of the human body. Natural maintenance of the length of the telomeric region appears to prevent genomic instability and helps to curb the development of cell mutations that may lead to cancer.

Read more about Hayflick Limit:  Cell Phases, Telomere Length

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