Junk DNA Revisited
Silicon Valley startup claims to have unlocked a key to its hidden language

San Francisco Chronicle

Hal Plotkin, Special to SF Gate

November 21, 2002

When the human genome was first sequenced in June 2000, there were two pretty big surprises. The first was that humans have only about 30,000-40,000 identifiable genes, not the 100,000 or more many researchers were expecting. The lower -- and more humbling -- number means humans have just one-third more genes than a common species of worm.

The second stunner was how much human genetic material -- more than 90 percent -- is made up of what scientists were calling "junk DNA." The term was coined to describe similar but not completely identical repetitive sequences of amino acids (the same substances that make genes), which appeared to have no function or purpose. The main theory at the time was that these apparently non-working sections of DNA were just evolutionary leftovers, much like our earlobes....

The notion that at least certain parts of junk DNA might have a purpose appears to be picking up steam. Many scientists, for example, now refer to those areas with a far less derogatory term: introns....

Other investigators are also looking into introns from a variety of perspectives. A group at UC Berkeley, for example, recently won $14 million from the National Institutes of Health to study the role introns might play in cardiovascular disease. Other researchers have begun looking at similar questions, with most focusing on intron strands located near genes whose functions are better understood. Scientists at UCLA, for example, recently made a promising association between what appears to be an intron abnormality and spinocerebellar ataxia, which is similar to Huntington's disease....

Thinking about whether junk DNA has a purpose "is a rather obvious question for scientists to ask," ... [Rest of the archived Berkeley article is omitted, AJP, 15th of July, 2005]