Rheumatoid arthritis, or RA, is an autoimmune and inflammatory disease that primarily affects joints. The disorder is characterized by warm, painful swelling most commonly in the wrists and hands.

All known life on Earth stores genetic information using the same four-letter DNA alphabet. Researchers have now shown that ...

Narwhals have nature's only straight tusk, a single tooth up to three meters (10 feet) long, so strange they were sold as ...