LETTER TO THE EDITOR: HOW TO FIGHT CANCER CELLS BY MAKING USE OF MUTATION IN DNA

Human bodies are made up of trillions of cells and each cell contains about 3 billion bits or gene sequences specifying the quality and type of those cells; out of which 99.9% are identical in all humans, 0.1% of them are not identical. Some of the cell quality is specified by a single deoxyribonucleic acid (DNA); for example a disease called sickle-cell anemia is caused by a single mutation in a single DNA base pair resulting in replacement of thymine amino acid by adenine amino acid. The result of this is that the shape of red blood cells will look like a sickle instead of donut shape. Red-green blindness is caused also by a single mutation. But not every trait is specified by a single sequence of DNA; for example red-green cone cells (about 7 millions of them) in the retina sense all wavelengths within the visible light 400-700 nm. Normal people have at least one red opsin gene and usually more than one green opsin genes. Color defective people do not have green opsin gene, but most of the normal people have several copies of green opsin genes (normally three or more) following a single red opsin gene.