Interesting article in todays edition of "The Australian" newspaper:
Cut-Price shortcut to what ails us
A shortcut developed by Australian scientists could slash the costs of genetic analysis by 95 per cent, fast-tracking cures for common illnesses such as dementia, schizophrenia and heart disease.
Queensland researchers say their new method of "imputing" genetic mutations allows DNA to be analysed for as little as $70 a pop, with only marginally less precision than full genomic sequencing that costs 20 times as much. The technique, outlined this morning in Nature Genetics, offers a cost effective way to analyse huge banks of tissue samples. "The greater the sample size the increased statistical power of the result," said lead author Jian Yang, from the Queensland Brain Institute at the University of Queensland. "When we study the genome for genes linked to diseases we need to test tens or even hundreds of thousands of samples because for most common diseases the effect of a single gene is tiny."
Advances have cut the cost of genome sequencing colossally, from $US119 million ($166m) in 2001 to about $1400. The new approach slashes costs further using tests known as "single nucleotide polymorphism arrays", which directly measure only a fraction of the genome.
Geneticists then guess the remaining DNA variants based on known genetic associations, using statistical imputation.
Last week University of Hong Kong researchers unveiled their own "user-friendly" imputation software tool and Californian company 23andMe uses imputation methods in a saliva test that costs consumers about $138.
Doubts over accuracy led the US Food and Drug Administration to stop 23andMe from using its tests for health advice in 2013, putting it out of the genetic testing business for 15 months.
But the UQ researchers say they have put these concerns to rest. In a study of more than 44,000, their imputation technique obtained results almost on par with full sequencing.
Project leader Peter Visscher said, while full sequencing would still be used to hunt for cures for rare illnesses, imputation could become favoured for some of the most common scourges.
"(They are) the diseases where we already know that there are hundreds - if not thousands - of variants that contribute to risk," he said.
