New Technology Uncovers Thousands of Never-Before-Seen Human Genome Variations

It's a huge step forward when it comes to understanding our own genetics. Scientists have uncovered thousands of never-before-seen genetic variants in the human genome using a new genome sequencing technology. The findings may help close many human genome mapping gaps that have long resisted sequencing.

The new method is called single-molecule, real-time DNA sequencing (SMRT). This technique may make it possible for researches to identify potential genetic mutations behind many conditions whose genetic causes have long eluded scientists.

So far, scientists have only been able to identify the genetic causes of about half of inherited conditions. This problem has been called the "missing heritability problem." It's possible that this problem is due to the fact that standard genome sequencing technologies cannot map many parts of the genome precisely. These approaches actually map genomes by aligning hundreds of millions of small, overlapping snippets of DNA, typically about 100 bases long, and then analyzing their DNA sequences.

And yet the new SMRT technology may give scientists the leg up that they need. The method makes it possible to sequence and read DNA segments that are longer than 5,000 bases, which is far longer than the standard gene sequencing technology. This, in turn, could help fill in gaps in the genome and may help scientists pinpoint areas that are responsible for inherited conditions.

"In five years there might be a long-read sequence technology that will allow clinical laboratories to sequence a patient's chromosomes from tip to tip and say, 'Yes, you have about three to four million SNPs and insertions deletions but you also have approximately 30,000 to 40,000 structural variants," said Evan Eichler, one of the researches, in a news release. "Of these, a few structural variants and a few SNPs are the reason why you're susceptible to this disease.' Knowing all the variation is going to be a game changer."

The findings are published in the journal Nature.