What are nuclear mutations?

All of the information in our body is written in a ‘library’ of information called the genome Each of the ‘books’ in the genetic ‘library’ is called a gene, and contains instructions for building and maintaining our cells and tissues. The ‘letters’ in these ‘books’ are made of a substance called DNA. Most of our genes are located in the heart of the cell, in a place called nucleus; these are called nuclear genes. Mutations are permanent damage to genes, and mutations that occur in nuclear genes are thus called nuclear mutations. Mutations are almost always harmful, interfering with the normal functioning of the gene.

How does the damage set in?

Toxic chemicals from the environment can damage genes, as can “free radicals” produced during the body’s own metabolism, but most mutations are like printer’s errors, produced during the process of maintaining and copying the nuclear DNA. And just like a photocopy of a bad photocopy, once an error has set into the nuclear genes it is passed on to all subsequent copies that are made.

Resultant disease

Some mutations can kill cells in very small populations (where the loss of even a few cells can have a significant effect on function), or cause cells to enter into a state that makes them toxic to their neighbors (so that damage to just a few isolated cells causes problems to normal cells around them). However, these are only minor problems over the course of a normal lifetime. The most dangerous disease caused by nuclear mutation is cancer.

Solution

Many scientists are working on new treatments for cancer, but these are very rarely permanent, and most cancers recur later on in life. Some scientists are now working on a very ambitious but potentially far more comprehensive and long-term approach to combating cancer than anything currently available or in development. It is based on the one inescapable vulnerability that all cancer cells share in common: their absolute need to renew their telomeres, which are the long stretches of gibberish DNA that cap the ends of the structural assemblies of genes. Telomeres fulfill a role that is similar to that of the nibs on the tips of your shoelaces, keeping the DNA from becoming frayed and unraveled.

Each time a cell reproduces, the telomeres become a little worn down, and when a cell runs out of telomeres it quickly self-destructs. Because cancer cells reproduce at a furious pace, they quickly reach the ends of their telomeric “ropes,” and need to find a way to exploit the cell’s natural machinery for renewing telomeres to restore normal telomere length, or their growth will come to an end. The thorough elimination of the genes that renew telomeres from all of our cells would thus spell the doom of cancer. Then, to avoid cell loss and tissue atrophy, we would need an aggressive program of stem cell therapy to keep our tissues renewed.