In a development that Darwin himself could not have foreseen, a beagle has become the world's first transgenic dog - and it glows in the dark

The dog called Ruppy - short for Ruby Puppy - has been created by scientists in South Korea.

The puppy was bred to produce a fluorescent protein that glows red under ultraviolet light, but it's red skin colour can also be clearly seen in daylight.

Byeong-Chun Lee, of the Seoul National University, headed the team that created Ruppy and her four beagle siblings, each possessing the bizarre fluorescent bodies.

Lee was also part of the team responsible for the very first cloned dog, Snuppy, born in 2005.

Team member CheMyong Ko of the University of Kentucky in Lexington, said of the breakthrough: "The next step for us is to generate a true disease model."

The hope is that, following the Ruppy breakthrough, transgenic dogs will become more effective stand-ins for the study of human disease.

Reactions to the announcement from other scientists studying dogs as models of human disease was mixed.

Greg Barsh, a genetist at Stanford University, said the creation of a transgenic dog was "an important accomplishment".

But he did not know of "specific situations where the ability to produce transgenic dogs represents an immediate experimental opportunity".

Nathan Sutter, of Cornell University in New York, said working with laboratory-reared dogs was "not on my horizon as a dog genetist at all", claiming "transgenesis is laborious, expensive and slow."