Further Models
After Cairns first proposed the immortal DNA strand mechanism, the theory has undergone several refinements.
In 2002, he proposed that in addition to using immortal DNA strand mechanisms to segregate DNA, when the immortal DNA strands of adult stem cells undergo damage, they will choose to die (apoptose) rather than use DNA repair mechanisms that are normally used in non-stem cells.
Emmanuel David Tannenbaum and James Sherley developed a quantitative model describing how repair of point mutations might differ in adult stem cells. They found that in adult stem cells, repair was most efficient if they used an immortal DNA strand mechanism for segregating DNA, rather than a random segregation mechanism. This method would be beneficial because it avoids wrongly fixing DNA mutations in both DNA strands and propagating the mutation.
Read more about this topic: Immortal DNA Strand Hypothesis
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