Structural analysis of genomes concerns copy number variation (multiple copies of genes), inserted genes, deleted genes, inverted genes and other structural changes, and is found in all classes of traits and disease. There is thought to be 12% structural variation between humans as opposed to 0.1% SNP variation between humans. SNP variation is the 'typos' at specific genetic locations where the normal nucleotide combination is 'AA' and some people have the risk alleles 'AT' or 'TT.”
Using exomes (the 1-2% of the genome that contains protein coding regions) as a cheaper alternative to whole human genome sequencing, and conducting basic SNP analysis together with more complex structural variation analysis, and possibly methylation analysis (which genes are blocked from expression), and RNA transcriptome analysis (levels of DNA expression), could bring more sophistication to DNA analysis for myriad purposes including pharmacogenomics and disease analysis.
Some interesting startup companies are starting to realize these new aspects of genomic medicine:
- Cellular Dynamics, Madison WI (human cells derived from induced pluripotent stem (iPS) cells)
- Integrated Diagnostics, Seattle WA (predictive blood assays of organ-proteins; UCLA melanoma clinical trial)
- Population Diagnostics, Melville NY (copy number variation analysis for pharmacogenomics)