Pharmacogenomics

Inappropriate prescribing of strong painkillers following surgery is partly to blame for a growing opioid crisis in the UK, experts have warned. Recent media reports that Britain is in the midst of an opioid epidemic come in the wake of huge increases in opioid prescriptions and soaring addiction rates, as well as growing numbers of overdoses and deaths linked to opioid use.


Strong painkillers are believed to have killed more than 91,000 people over the past two years. Despite evidence showing that these drugs are ineffective at relieving pain after more than a few days, there is a growing tendency for doctors to prescribe the drugs, which are highly addictive, for chronic pain.

Addressing the problem

The problem has been growing since the late 90s both here and in the US where it was declared a public health emergency in autumn 2017. Among the steps being taken to address the problem are increased monitoring of prescriptions, access to treatment for opiate addiction and research into new non-addictive painkillers.

In addition, scientists are proposing that genetic testing could help to address the problem by identifying people who might be predisposed to becoming addicted to opioids.

The role of genetics in addiction

There has been much speculation about whether there is a genetic component to addiction, with researchers pointing to studies involving twins which suggest a predisposition to alcohol and drug addiction.

Further studies suggest that genetic factors might play a significant role in the development of addiction – as much as 40-60% in some cases.

More work is needed in this area to be able to predict with accuracy whether someone is likely to become addicted to opioids and researchers are at pains to point out that just because someone is vulnerable to addiction does not mean that they definitely will become addicted.

Nevertheless, recent research has confirmed that impairment of a particular gene, casein kinase1-epsilon (CSNK1E) not only increases the likelihood of someone becoming addicted to opioids but also makes women more likely to binge eat.


Research study

Researchers at Boston University Medical Center found that when CSNK1E is dysfunctional the euphoric response to opioids increases and there is a greater sensitivity to binge eating. Genetic variation in CSNK1E could act as a risk factor for addiction and may indicate that the patient should be given non-opioid drugs for pain relief and/or therapeutic treatment.

The same research team also suggested that CSNK1E may play a role in addiction to alcohol and advised that more research is needed into the potential interaction of the gene with circadian biology linked to addiction.

Promising early results

Genetic testing for drug addiction is an evolving area of research and there isn’t yet a simple test that could show someone’s genetic propensity to addiction However, early results are promising and it is likely that a simple cheek swab might be used in the future to risk test someone’s potential for opioid addiction.

Current research is focusing on a number of areas, including analysing opioid receptor genes such as mu, kappa and delta. Scientists already know that the mu opioid receptor (OPRM1) plays a key role in the perception of pain and addiction. Genetic variants of OPRM1, such as the single nucleotide polymorphism A118G, are implicated in the predisposition to addiction to opioid drugs.


At the forefront of Pharmacogenomics in the UK

Myogenes is one of the genetic testing companies at the forefront of pharmacogenomics, which is the tailoring of medical treatments to individual needs based on their genes.

Pharmacogenomics is based on the fact that someone’s response to medication is influenced by their genetic make-up.

This means that genes can be tested to determine:

  • Whether a medication is likely to be effective.
  • What the most appropriate dosage will be.
  • If there are likely to be any side effects.

In the future this branch of genetics could prove an invaluable resource in preventing opioid addiction and halting inappropriate prescribing.


Next steps

For more information about pharmacogenomics speak to your GP, consultant or clinician, or call the friendly team at Myogenes.