TUESDAY, Dec. 14 (HealthDay News) -- Most of the human embryonic stem cell research conducted in the United States is funded by states, not the federal government, a new study reveals.

The study also found substantial variation in the extent to which states prioritized human embryonic stem cell research, and that much of the research performed in states could likely have been funded under federal government guidelines established in 2001.

Study author Aaron Levine, an assistant professor at the Georgia Institute of Technology, created an online searchable database that offers detailed information about stem cell research grants handed out by six states -- California, Connecticut, Illinois, Maryland, New Jersey and New York -- between December 2005 and December 2009. The database will be updated each year.

"While the federal government still contributes more to stem cell research overall, each year since 2007, these six states have funded more human embryonic stem cell research than the federal government," Levine said in a Georgia Tech news release.

"From what I could tell, only a relatively small portion of the stem cell research supported by these states was clearly ineligible for federal funding," he added.

The share of stem cell funding given for human embryonic stem cell research varied widely -- from 97 percent in Connecticut and 75 percent in California to only 21 percent in New Jersey and New York.

Levine said this may be because some states, such as New York, are focusing on a new technology called induced pluripotent stem cells, which are derived from adult body cells rather than embryos.

The study was published in the Dec. 7 online edition of the journal Nature Biotechnology.

More information

The U.S. National Institutes of Health has more about stem cells.