Evolutionary biologists from McMaster University have reviewed decades of research in the hopes of understanding why precision medicine has not been fully integrated into modern healthcare.
Over 20 years ago, scientists implied that the adoption of precision medicine will be made upon the completion of the Genome Project. Now, 17 years since the project ended, precision medicine has yet to be fully integrated into western healthcare.
Two researchers from McMaster University, Canada, have offered insight into why the promise of precision medicine has yet to materialise. The team suggests that the sophistication of the human genetic blueprint has a more complex and far-reaching influence on human health than scientists had first realised.
Reviewing decades of precision medicine
McMaster evolutionary biologists Rama Singh, PhD, and Bhagwati Gupta, PhD, have carried out an exhaustive review of decades of research in the hopes of furthering the integration of genetics in medical practices.
Published in Genomic Medicine, McMaster researchers titled their review ‘Genes and genomes and unnecessary complexity in precision medicine’. Singh and Gupta wrote: ‘The sequencing of the human genome heralded the new age of ‘genetic medicine’ and raised the hope of precision medicine facilitating prolonged and healthy lives.
‘Recent studies have dampened this expectation, as the relationships among mutations (termed ‘risk factors’), biological processes, and diseases have emerged to be more complex than initially anticipated. In this review, we elaborate upon the nature of the relationship between genotype and phenotype, between chance-laden molecular complexity and the evolution of complex traits, and the relevance of this relationship to precision medicine.’
Complex and interconnected molecular pathways
Authors note that chance-driven molecular changes, in conjunction with the blind nature of evolutionary processes can create genetic redundancy or multiple molecular pathways to the same phenotype. As time goes on, these pathways become more complex, interconnected, and hierarchically integrated.
The paper states: ‘In the short term, unnecessary complexity can give rise to similar risk factors with different genetic backgrounds; in the long term, genes become functionally interconnected and integrated, directly or indirectly, affecting multiple traits simultaneously. We reason that in addition to personal genomics and precision medicine, unnecessary complexity has consequences in evolutionary biology.’
“The idea has long been that individual genetic mutations could be classified as good, bad or neutral,” Singh says “Genes, though, do not work alone, and so no single gene can be considered to be good, bad or neutral in all contexts.”