There is no known cure for the virus, responsible for making millions cough and sneeze every year and which can also trigger asthma attacks. Now, an international team has mapped the DNA or "instruction manual" for 99 strains of the cold.

In their study, the scientists have uncovered how the virus has evolved constructing a "family tree", and identified what they believe are vulnerabilities which could be targeted by new medications, the 'Science' journal reported.

In fact, the study has shown for the first time that different strains can "swap genes" creating new strains of the virus, suggesting there would never be an effective vaccine.

"Having sequenced the complete genomes of these things we now know you can be infected by more than one virus at a time and that they can recombine (their genes)," said Ann Palmenberg of Wisconsin-Madison University, who led the study.

"That's why we'll never have a vaccine for the common cold. Nature is very efficient at putting different kinds of paint on the viruses," 'The Daily Telegraph' quoted Palmenberg as saying.

According to the scientists, the study also found that the viruses were organised into about 15 small groups, clearly suggesting that a "one drug fits all" approach would not work neither would a jab be effective.

"There has been no success in developing effective drugs to cure the common cold, which we believe is due to incomplete information about the genetic composition of all these strains.