BAR HARBOR (AP) – Marine scientists have identified more than 5,000 genes as part of a project to identify the lobster’s genetic code to help researchers learn ways to protect Maine’s most valuable fishery resource.

Scientists at the Mount Desert Island Biological Laboratory have spent the past five months identifying genes that make up a lobster’s biological blueprint.

David Towle, lead researcher on the project, said he and his research partners in December began sampling tissue from the lobster’s major systems: its heart, brain, glands, muscles and reproductive organs.

They have used those samples to map lobster DNA, which contains the genetic code and transmits the hereditary pattern.

There’s no telling how many genes will have to be sequenced before the full lobster genome is known. But the number will likely run into the tens of thousands, Towle said Friday while explaining his work to colleagues and students during the 31st Maine Biological and Medical Sciences Symposium at the MDI Biological Laboratory.

“What we really need is 50,000, rather than 5,000,” Towle said.

The researchers use a sequencing machine, purchased with funding from the Maine Science and Technology Foundation, to identify between 500 and 1,000 of the individual nucleotides that make up any given gene.

While these “tags” – long strings of the frequency and pattern of nucleotides – don’t make up the entire strand, it’s typically enough to identify a gene as unique, Towle said.

About half of the lobster genes identified so far have comparable genes in species like mice and humans that have been mapped in full, so scientists know their purpose. Genes across species are surprisingly similar – 99 percent of human genes have a similar companion gene in a mouse, according to researchers at Bar Harbor’s Jackson Laboratory.

The other 2,500 genes identified for lobsters were previously unknown, Towle said.

The human genome contains between 30,000 and 40,000 genes, as does the genetic blueprint for the mouse and for a corn plant. Even the fruit fly has about 17,000 genes, researchers have found.

Elsewhere, partner institutions like the Hollings Marine Library in Charleston, S.C., are sequencing the genes of other marine organisms, such the blue crab.

AP-ES-05-02-04 1230EDT