Just 6 years after scientists decoded the human genome, a line of research derived from the breakthrough known as personal genomic medicine is increasingly perceived to be an expensive bear with an uncertain future, according to commentaries in the New England Journal of Medicine.
Since the heralded announcement in 2003, geneticists have undertaken hundreds of genomewide association studies designed to compare the DNA of healthy people with those of patients having specific diseases.
The hope was to pinpoint a handful of culprit genes and by association, biochemical processes that could become targets for disease-modifying drugs, immune therapy or what have you.
But the studies appear capable of explaining just a fraction of the genetic component underlying complex diseases like cancer, schizophrenia and diabetes.
The problem, it seems, has been the assumption that such conditions were promoted by variations in a small number of genes, say 10. Instead, thousands of genes appear to be involved, with multiple variations at each locus exerting myriad effects on other genes and their variants.
The snafu represents a setback for personal genomics companies that hoped to inform customers about their risk for these diseases.
“With few exceptions, what the genomics companies are doing right now is recreational genomics,” Duke University geneticist David Goldstein told the New York Times. “The information has little or…no clinical relevance.”
In his NEJM piece, Goldstein therefore recommends a strategic shift in genomics research towards decoding the entire DNA of patients with certain diseases.
But Peter Kraft and David Hunter of the Harvard School of Public Health, publishing in the same issue, remain optimistic about genomewide association studies.
“There will be more common variants to find,” Hunter told the Times. “It would be unfortunate if we gave up now.”