ALBANY, N.Y.(AP) -- The nation's richest prize in medicine and biomedical research was awarded Friday to two researchers for work that has improved disease treatments and may lead to new ones for degenerative and other age-related disorders.

Joan Steitz and Elizabeth Blackburn are the first women ever to receive the 8-year-old Albany Medical Center Prize. They will share the $500,000 award, which ranks second only to the $1.4 million Nobel Prize among medical prizes.

Steitz, a professor at Yale, is known for research that has improved the diagnosis and treatment of certain autoimmune diseases, including lupus, scleroderma and some forms of arthritis. She discovered the function of small ribonucleoproteins, called snRNPs, that play a vital role in producing proteins for the body's most basic biological processes.

Blackburn, of the University of California, San Francisco, made groundbreaking discoveries about structures called telomeres on the tips of chromosomes. Telomeres are like the plastic tips on the end of shoelaces — they hold chromosomes together to keep them from fraying.

Blackburn discovered an enzyme called telomerase, which repairs telomeres as they wear down. The more telomerase people have, the less likely they will get cardiovascular problems, Blackburn said. Chronic stress correlates with having a lower level of the enzyme.

Telomerase also has a dark side: It can contribute to the growth of cancer cells, a discovery that could eventually help in the treatment of some cancers.

The Albany prize was established in 2000 with a $50 million gift from the late Morris "Marty" Silverman, a New York City businessman who wanted to encourage health and biomedical research.

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