Behold the MitoChip 2.0: Zhou et al. report the advent of full sequencing of the mitochondrial genome, including that tough-to-scratch D-loop region, on a single tiled oligonucleotide array:
Previously we developed an oligonucleotide sequencing microarray (MitoChip) as an array-based sequencing platform for rapid and high-throughput analysis of mitochondrial DNA. The first generation MitoChip, however, was not tiled with probes for the noncoding D-loop region, a site frequently mutated in human cancers. Here we report the development of a second-generation MitoChip (v2.0) with oligonucleotide probes to sequence the entire mitochondrial genome. In addition, the MitoChip v2.0 contains redundant tiling of sequences for 500 of the most common haplotypes including single-nucleotide changes, insertions, and deletions. …
The authors emphasize the application to detection of tumor-associated mitochondrial mutations, but it’s hard to miss the potential utility of rapid, accurate, sensitive mitochondrial resequencing to aging research.
Mitochondrial mutation has been implicated in cellular aging in general but also in specific age-related diseases and conditions such as hearing loss. The ability to quickly identify mitochondrial genome changes in small numbers of cells will certainly accelerate the discovery of common mutations associated with age-related decline in a variety of tissues.
With the resequenced mitochondrial genome soon to be just a chip away (I’m not yet sure what the commercialization model is for this technology, but the price range for mass-produced chips is well below $1000 a pop and still falling), I’m betting we’ll see a large number of aging labs starting to ask questions relating mitochondrial mutation to their system of interest. Is there a relationship between telomere length and mitochondrial genome change? It’s just a chip away. Do we see early or delayed senescence in cells with certain mitochondrial mutations (or haplotypes)? It’s just a chip away.