Human Genome Sequencing Poised to Enter the Clinical Arena

A recent paper described a low-cost DNA sequencing and haplotyping process, long fragment read (LFR) technology, which is similar to sequencing long single DNA molecules but without cloning or separation of metaphase chromosomes.

A haplotype is a combination of alleles at adjacent loci on the chromosome that are transmitted together. A haplotype may be one locus, several loci, or an entire chromosome depending on the number of recombination events that have occurred between a given set of loci. Alternatively, haplotype describes a set of single-nucleotide polymorphisms (SNPs) on a single chromosome of a chromosome pair that are statistically associated. It is thought that these associations, and the identification of a few alleles of a haplotype block, can unambiguously identify all other polymorphic sites in its region. Such information is very valuable for investigating the genetics behind common diseases.

Complete Genomics, Inc. (Mountain View, CA, USA) has developed advanced informatics and analysis systems in order to provide whole human genomic information to better understand the prevention, diagnosis, and treatment of diseases.

In a study published in the July 11, 2012, online edition of the journal Nature investigators from Complete Genomics demonstrated the versatility of the LFR process by creating ten LFR libraries using only about 100 picograms of human DNA per sample.

This is the amount of DNA that can be obtained from as few as 10 to 20 cells, making LFR an ideal choice for small sample clinical sequencing applications including circulating tumor cells, fine needle aspirations, and preimplantation genetic diagnostics.

“The Nature paper describes how our LFR technology uses “barcoded” DNA to generate whole genome sequencing with approximately one error in 10 million base pairs, or just 600 errors in an entire human genome,” said senior author Dr. Rade Drmanac, CSO at Complete Genomics. “This represents a 10-fold increase in accuracy for Complete and is unmatched by any high-sensitivity method currently available.”

“We expect the introduction of this technological breakthrough to accelerate the move of whole genome sequencing into patient care, which in turn will begin to change the face of medicine,” said Dr. Clifford Reid, president and CEO of Complete Genomics.

Complete Genomics has already been granted two [US] patents on LFR technology, and additional patent applications, including miniaturization using nanodrops, are pending.

Related Links:
Complete Genomics, Inc.