Genetic diseases result from flaws in the body\'s instruction code or DNA that lead to the cells not functioning or developing as they should. But, in what is claimed to be a world first, scientists claim they have come up with an entirely new way to rewrite the code – reversing any flaws or faults. \"This is a really powerful concept that can be used to try to suppress the tendency of individuals to get certain debilitating, and sometimes fatal genetic diseases that will forever change their lives,\" said Dr Robert Bambara, at the University of Rochester, in New York. The findings, though early, are significant because they may ultimately help researchers alter the course of devastating genetic disorders, such as cystic fibrosis, muscular dystrophy and many forms of cancer. More than 8,000 people in Britain suffer from cystic fibrosis, including Gordon Brown\'s son, Fraser. A further 30,000 people have muscular dystrophy. Both diseases are highly debilitating and lead to shortened lifespans. The genetic code is the body\'s own instruction manual and tells it how to develop and how to function. This is mainly done through the production of proteins and these can be affected by faults or mutations in the reading of the strands of DNA. One common type of mutation is when a premature \"stop\" or \"codon\" signal occurs and this orders a cell to stop reading the genetic instructions part-way through the process, resulting in the creation of an incomplete, shortened protein. These incomplete proteins are what cause a third of genetic conditions such as cystic fibrosis, muscular dystrophy and could contribute to cancers. Now the researchers, who published results the journal Nature, claim to be able to turn the stop signal into a \"go\" signal. As a result, the cell could read the genetic instructions all the way through and create a normal, full-length protein. The team have produced these results both in a test tube and in live yeast cells but if they hope to eventually use them in the body. \"This is a very exciting finding,\" said Professor Yi-Tao Yu, lead study author. \"No one ever imagined that you could alter a stop codon the way we have and allow translation to continue uninterrupted like it was never there in the first place.\" Dr Bambara said: \"The ability to manipulate the production of a protein from a particular gene is the new miracle of modern medicine.\" The system works by altering a messenger in the body called mRNA which usually transfers the instructions of the DNA to the cells to make the proteins. At present there are no cures for genetic disease and the medical profession has concentrated on prevention, screening children in the womb for any risks.