Genomics is increasingly hailed by many as the turning point in modern medicine. Advances in technology now mean we’re able to make out the full DNA sequence of an organism and decipher its entire hereditary information, bringing us closer to discovering the causes of particular diseases and disorders and drugs that can be targeted to the individual.
Buzzwords like “whole genome sequencing” and “personalised medicine” are everywhere – but how are they enabling a powerful medical and societal revolution?
It all started in the 1990’s with the Human Genome Project – a very ambitious venture involving 20 international partners and an investment of US$3 billion. In 2003, 13 years after it began, the project yielded the first complete human genome. Today, the cost of sequencing whole genomes is plummeting fast and it is now possible to do the job for less than US$1,000, meaning a whole host of applications both in research and in treatments.
Variants And Mutations
Genetic mutations are often linked to disorders, predisposition to diseases and response to treatment. For instance, inherited genetic variants can cause blood disorders such as thalassaemia or others such as cystic fibrosis or sickle cell anaemia.
Genome sequencing is being used today in diagnostic and clinical settings to find rare variants in a patient’s genome, or to sequence cancers’ genomes (to point out genomic differences between solid tumours and develop a more effective therapeutic strategy). It is also possible to test for known simple mutations via a process called genotyping, which can find genetic differences through a set of biomarkers. In the case of thalassemia, for example, there are mutations in the HBB gene on chromosome 11.
A number of drugs, including blood-thinners like warfarin, have already been commercialised with genetic markers (such as a known location on a chromosome) linked to effectiveness and correct dosage.
However, the availability of a patient’s fully sequenced genome will only make it easier and quicker to run complex tests, using computational algorithms (the data analysis tools we use to search and process digital information) as opposed to more expensive and slower biological tests.
With costs likely to drop below that of an MRI scan (hundreds of pounds in the UK, thousands of dollars in the US), it is inevitable that sequencing will become an important part of our healthcare system – provided that the right tools for data analysis are developed alongside sequencing technologies.
The exciting and fast-paced progress of whole genome sequencing also fosters the dream of personalised medicine – tailoring medical care to the individual patient’s genetic makeup. Personalised medicine is already happening in clinical settings – including adjusting drug dosages and deciding the best treatment course for a leukemia, HIV, and colorectal cancer – but also at a consumer level with direct-to-consumer (DTC) genetic testing ventures such as 23andme.
For £125 and a sample of saliva, 23andme will probe part of your genome – genotyping hundreds of thousands of variants and mutations and comparing data with thousands of others on a database before delivering reports on inherited traits, genealogy, and congenital risk factors. And through Ancestry.com you can trace your ancestral lineage.
But cheap sequencing is also considered a key enabler of research in medical and evolutionary genomics. Access to large numbers of digitised genomes empowers researchers to more effectively study existing relationships between genetic features and diseases, cancers, and treatments – and to discover new ones. This yields large investments – as well as expectations – from both the private and public sectors.
Great Power, Great Responsibility
With great power, of course, comes great responsibility. And all of these developments raise important ethical concerns. From a data protection point of view, dissemination of genomic information could be extremely dangerous due to its sensitivity.
The human genome not only uniquely identifies its owner, but it also contains information about ethnic heritage, predisposition to diseases and conditions, including mental disorders like schizophrenia. This often prompts fears of eugenism (genetic discrimination), which has potentially dreadful implications for social dynamics, as new hiring and health insurance practices. Due to its hereditary nature, disclosing one’s genome also essentially implies disclosing the genomes of close relatives.
To further compound the issue, rapid developments in genomics are often promoted as being dependent on facilitating and encouraging sharing of data between different research teams and institutions.
Recent public initiatives, such as the Personal Genome Project, aim to create public datasets for research purposes, involving volunteers who agree to have their genome sequence made publicly available, for “the greater good”. The UK also announced an investment of £100m and a plan to fully sequence the genome of 100,000 patients by 2017. These initiatives essentially require patients and donors to forego their privacy expectations but, in fact, genomic anonymisation – removing identifiers to conceal the identity of the genome owner – is hardly effective, because the genome is by nature a unique identifier.
Melissa Gymrek, a PhD student in bioinformatics at MIT/Harvard, and colleagues were recently able to re-identify DNA donors from a public research database using only information available from genealogy websites. Also, masking sensitive portions of the genome – such as mutations that indicate predisposition to Alzheimer’s disease – is almost impossible because the correlation between one or multiple mutations can often be used to reconstruct the “redacted” features.
In the near future, relevant policy efforts will be needed alongside technical advances to protect security and privacy. At the very least, we need to regulate the growing market for genetic testing, through appropriate data protection legislation and requirements for effective and meaningful informed consent. And system and application developers need to work closely, not only with security experts, but also with ethnographers and psychologists to better understand, and more effectively address, individuals’ concerns.
On the bright side, because the field is relatively new, we have a unique opportunity to build privacy by design, embedding privacy and data protection into systems right from the start, rather than being bolted on afterwards.
Wonder Of Science