Can an entire human be written out in letters?

That time, that place

The project began in 1990: read all three billion letters of the human genome from beginning to end.

It took thirteen years and three billion dollars. Midway a private company entered with a much faster method, and in 2000 the rivalry was settled by a joint announcement.

Why this question

What would reading it all reveal?

The widespread expectation was that once each gene's function was known, the causes of disease could be located in genes and corrected.

The expected gene count was around a hundred thousand. Humans are complicated, so there must be many.

What was found

The results missed the expectations in several directions.

There were about twenty thousand genes — not even twice a fruit fly's. Human complexity does not come from the number of genes.

And the protein-coding portion is under two percent of the whole. Most of the rest had no known function and was for a while called junk. Much of it is now known to be involved in switching genes on and off, and much remains unknown.

One more thing was confirmed. Looking at genetic variation among people, the differences within any population are far greater than the differences between populations. There is no biological basis for race as a category.

Terms on this card

Genome