There is a living database of yeast in the U.K. Norwich's National Collection of Yeast Cultures holds more than 4,000 strains of yeast, packed away in tiny freeze dried ampules and in live cultures. About 800 of them are used for brewing.
Megan Garber at the Atlantic writes:
Brewers can house their strains securely as well as deposit them in an open collection; this gives other brewers the possibility of using that yeast for their own creations. (If you want buy some, you can do so here.) Today's microbrewers are eager to make new concoctions with yeast from the 1940s, Chris Bond, the collection manager, tells Rogers. (And once, "we actually had someone trying to recreate a South American beer from the Incas," he notes.) You can think of the Center as a strain, if you'll pardon the pun, of the Svalbard Global Seed Vault in Norway—an archive meant to preserve our bio-heritage. The Center treats microbes not just as ingredients in some of humanity's oldest recipes (beer! booze!), but also as part of a heritage worth preserving in its own right. It recognizes our cultural reliance on microbes.
The National Collection of Yeast Cultures, in addition to being a living library, also does a lot of testing. Want to know if the yeast your company is using to brew beer contains one strain of yeast or multiple? They do DNA fingerprinting. They also do other kinds of yeast identification and R&D, but for a price. (People wanting to get strains of yeast for academic reasons do get a steep discount on yeast cultures.)
Of course, while plenty of valuable academic research is done on yeast strains, they are most renowned for being an integral part of the beer making process. The strain of yeast used in brewing a batch of beer can have a large impact on the resulting brew, which is why brewers are so interested in keeping their strains safe — little microbes can pack a large punch in brewing circles.