From C&EN Archives: Intrumentation

In 1986, Leroy Hood and his coworkers at California Institute of Technology reported the first automated DNA sequencer. This instrument paved the way for the international effort to sequence the human genome. On page 4 of its June 16, 1986, issue, C&EN described the development this way:

The machine, called a DNA sequenator, “is an extremely important advance because [with it] we can begin to think about setting up facilities for the really extensive sequence analysis of human chromosomes,” Hood explains. “Such analysis is vital to understanding genetic diseases and cancer because often only subtle differences exist between normal DNA and DNA involved in pathological conditions. To understand these diseases, researchers must discover what these subtle differences are and how they cause illness.”

The machine allows automation of many of the tasks of gene sequencing that until now have had to be done laboriously by hand. It likely will reduce both the time and the cost of doing sequence experiments. The commercial instrument, which Applied Biosystems expects to be marketing by the end of this year, will be capable of sequencing 500 DNA unit bases per hour and costs roughly $90,000. Researchers estimate that eventually the cost of determining a genetic sequence by machine will be pennies per base, compared with a present cost of $1.00 to $5.00 per base using manual techniques.

So far, the Caltech researchers have been able to determine the sequence for fragments of DNA several hundred bases long in one run. They expect improvements to allow sequencing of 1,000 base-unit DNA, which is roughly the size of individual human genes.

Since then, the instruments and chemistries used for DNA sequencing have continued to evolve and the price has continued to drop. And, thankfully, the word “sequenator” has been consigned to the linguistic dustbin.