THE price of sequencing a person’s genome — putting in order all three billion base pairs of DNA in a set of human chromosomes — keeps dropping. But interpreting the billions of letters in a person’s DNA blueprint for use in medicine, and keeping that highly personal information secure and anonymous, is still a complex task.

Over the past few years, the cost of mapping one person’s genome has dropped to around $6,000 from about $250,000, and it is expected to go far lower. And, as genomic medicine quickly evolves, a powerful computer packed with software has arrived to interpret sequences privately within the walls of a lab, in contrast to systems that use the Internet and distant servers. The software parses variants in DNA, looking for ones that may be important.

The appliance, made by a human-genome interpretation company called Knome, is the size of a file cabinet and costs $125,000. Knome will begin shipping it in coming months to researchers investigating the genetic basis for cancer, rare diseases and drug response, said Jorge Conde, a co-founder of the company along with Dr. George M. Church, a geneticist and professor at Harvard Medical School.