A retired scientist wants to trace the origins of his family name with the tool he knows best – genes.

Thomas Roderick, a retired geneticist from The Jackson Laboratory in Bar Harbor, is about to debut an online journal called the Journal of Genetic Genealogy, which he hopes will help others map their family trees.

“It’s a great kind of puzzle putting it together, and it’s just kind of unfolded in the last couple of years,” Roderick said.

When information is skimpy or family records are filled with gaps, a simple swab of DNA could prove a person descends from certain family branches, he said.

At the moment, DNA is most widely used to trace direct male lines or direct female lines. The Y chromosome that determines maleness – and is passed only from father to son – is inherited through generations and remains mostly unchanged.

Roderick said that if a man’s Y-line is virtually identical to another man’s Y-line, it’s possible they could share centuries-old ancestors.

The female line is inherited differently, but the genealogical and genetic consequences are the same. That line is traced through the mitochondrial DNA, which is passed to both males and females only from their mothers.

DNA tests can provide information that a genealogist may not be able to prove through more traditional methods of tracing wills, deeds and other documents.

Nancy Battick, president of the Maine Genealogical Society, says DNA will open new doors and settle longtime disputes for people researching their family trees.

“There have always been a lot of questions about certain lines because they could never find physical proof that families were connected,” she said. “DNA will give us a definitive answer.”

Some families have begun banking their test results at the Web site hoping to forge physical links with strangers to whom they may be related.

Melinde Lutz Sanborn, a New Hampshire genealogist, said lots of New England folks have heard rumors of an “Indian princess” in their family line because of the commingling of early European settlers with the native population.

DNA can either prove or disprove that old family tale.

“In the end, there are very few people who successfully trace in the records to an Indian person of any rank, let alone a princess,” she said.

Roderick, also one-time president of the Maine Genealogical Society, has used DNA to fill in gaps in his own family tree. His family will have a reunion in Idaho this summer, with relatives and “supposed relatives” from around the world.

Roderick said he would be sure to go armed with a few DNA test kits.