Genome sequencing: the speed is increasing

Biologists have learned to "read" individual DNA molecules
Tape.Roo

The new technology of decoding DNA sequences allows you to do this many times faster than existing techniques. The difference of the new method is that it determines the sequence of individual DNA molecules, and does not average the data obtained from the decoding of a set of molecules. The Nature News portal (Gene reading steps up a gear) writes more about the technology.

In order to determine the sequence of a sufficiently long DNA fragment, scientists determine the sequence of its shorter pieces, and then connect the resulting segments together. The average size of such pieces produced by a new technology developed by the biotechnology company Pacific Biosciences is about 15,000 nucleotides. Most of the existing techniques "give out" fragments approximately ten times smaller.

In order to test the capabilities of the new method, the authors used it to determine the DNA sequences of five strains of Vibrio cholerae cholera Vibrio cholerae. All the work was completed in less than five hours, while one of the fastest modern technologies developed by Illumina allows you to do it in about a week.

The main disadvantage of the new method is the low accuracy of the obtained sequences. It is about 85 percent, while today the 99 percent level is considered the norm. Low accuracy is a consequence of the fact that within the framework of the technology invented by Pacific Biosciences, individual DNA molecules are "read". The authors note that the accuracy can be significantly improved if the sequence under study is "read" a second time (however, the time required for decoding will increase).

The developers of the new method claim that by 2013 it will be possible to decipher the human genome in 15 minutes – now this process takes an average of a month.

Portal "Eternal youth" http://vechnayamolodost.ru09.02.2011