Some Glow fish, infact MANY and MOST Glow Fish do have altered DNA. However, many stores are using the Danio's resiliance to death to their advantage, and many danios are, sadly, being dipped in neon dye. here's an excerpt from an online article.
"Several hundred of the hardy fish, which can survive in brackish or fresh water, are being brought in by aquarium supplies wholesaler Adec Trading and Services, the sole distributor for Taikong products here. They will be sold at about 300 aquarium outlets here once the go-ahead is given, said Mr John Koo, Adec's managing director.
The fish are also expected to enter the United States market later this month, and Taikong said it will be producing more than 100,000 of the fish monthly. So far, only the neon-green version has been put on sale. But later versions will be produced and swimming in new, non-toxic and pernament dye, by hopefully the end of 2004."See? Many of these poor fish are infact be dyed. I shouldn't say that they are being "dipped", however. They are actually hatched from eggs in the dye, and survive in it untill they are sold. What a horrible thing to do to a fish!
Always stickin' up for myself

cheers
-Ross