Scientists on Thursday published the first complete human genome, filling in gaps remaining after previous efforts while offering new promise in the search for clues regarding disease-causing mutations and genetic variation among the world's 7.9 billion people.

Researchers in 2003 unveiled what was then billed as the complete sequence of the human genome. But about 8 percent of it had not been fully deciphered, mainly because it consisted of highly repetitive chunks of DNA that were difficult to mesh with the rest.

A consortium of scientists resolved that...