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Continuing our series celebrating ‘amazing people at Oxford who you should know about’,  ScienceBlog talks to Dayne Beccano-Kelly, an electrophysiologist and a Career Development Fellow in Oxford Parkinson’s Disease Centre, in the department of Physiology, Anatomy and Genetics at Oxford University.

With more than ten years’ experience in the field, Dayne discusses his research using human neurones to improve treatments and the quality of life for people with neurodegenerative conditions such as Parkinson’s disease. He also shares how he is aiming to tackle the lack of BAME leadership opportunities in STEM, by mentoring and inspiring black and minority ethnic scientists of tomorrow.

How would you describe your journey to Oxford?

I am from Cardiff originally, and took my undergraduate degree at Leeds University in bio-chemistry, as a route into medicine. But, after my first year, I changed my mind with a stint in research, as part of my year in industry.

Time and experience showed me that what I really wanted to do was science research, helping people, but being the one to garner the knowledge that would help. It is fun to be continually asking the questions, and driving the conversation on known scientific knowledge.

Was Oxford what you expected it to be?

Oxford is a melting pot of scientific ideas that are often brewing a stone’s throw away, which makes it easier to interact with other scientists and develop collaborations.

I have been here four years now and don’t feel marginalised at Oxford. I expected there to be a low number of BAME academics at Oxford, because there have been at every other institution.

Having lived in Vancouver directly before this, which I loved in a different way, I can feel the contrast. It’s great to be surrounded by so much history. Vancouver is younger than Arsenal FC, my football team.

What motivates you?

By understanding how Parkinson’s Disease works I am helping people every day. As a scientist, and on a personal level, that is one of the best things that we can do.

It is important to remember that there are people waiting for us to get this right. Meeting them patients as I/we do helps to consider them like members of my family. It makes you want to fight for them that little bit harder.

In a nutshell what is neuro electrophysiology?

Neurotransmitters are chemical messages that allow neurones to talk to one another.  When received by a neuron the information is changed into and transmitted as an electrical current. It is this combination of chemical and electrical signal that allows us to move, think, talk remember and everything in between. Neurodegenerative disorders affects this communication by causing neurons to degenerate and die. In Parkinson’s disease (PD) it is a specific set of cells that produce a neurotransmitter called dopamine which are under threat.  These control goal directed movement and cognition and it is why we see the symptoms we do in PD as these neurones are no longer able to do their job.   

Image credit: OUDayne and his colleagues from the Wade-Martins research group. Image credit: OU

How does your research support care improvements in this area?

My research focuses on converting adult human cells into stem cells, and then converting them into neurones so that we can test for changes in Parkinson’s Disease. The cells that we create are plugged into an open electrical circuit, which we use to measure how neurones talk to each other, via the chemical-electrical signals that I mentioned. I have focused my work on looking at the earliest possible changes we can see in this cross talk between neurones, and what this can tell us about what is going wrong in the condition. If we can understand this, we could begin to think of stopping the disorder in its earliest stages.

In the past this research has been conducted using animal cells, cell lines etc., but this is the first time we are able to use human neurones to investigate human disease in this way. Understanding these cell changes can help us to tailor medicines to better treat the condition.

How did you come to specialise in Parkinson’s research?

As a child I always wanted to be scientist, and naturally wanted to make people better. As a young boy, I apparently stood at the bottom of my arthritic grandfather’s bed, and said ‘I am going to fix you.’ So early on my path was set.

When I was studying at Leeds I was awarded a year in industry at the Mayo Clinic in America, and that sealed the deal. I had a great mentor there, the pathologist Dr. Dennis Dickson. His effervescence and passion for his work rubbed off on me and I just thought ‘man, this is what I want to do.’

My work there focused on Progressive Supranuclear Palsy – an atypical Parkinsonian disorder. I have worked on different neurodegenerative conditions throughout my career at different institutions in various parts of the world, including Scotland, Canada and the US.

What is the most surprising thing you have learned through your research?

As scientists we should just want to know the truth, however, not every scientist sees it that way and that baffles me. I heard a great quote from Prof. Diane Lipscombe at a conference I attended a few weeks ago, she said: “Always follow the data, it will always be more interesting than your imagination can ever generate.” I love that, I think it’s great to generate unexpected things; it’s another question to answer.

I also find it surprising and sad, that I have not encountered more black senior scientists in my career. I find that very jarring.

Has this lack of BAME mentoring opportunities affected your own career?

I’ve been driven enough to get to this stage by myself, but it’s an issue, It would have been nice to have a senior black individual that I could ask, ‘how did you do it? What were the things that you encountered? Was it the same as my experience, or am I just some kind of strange outlier?’

I work with black female and Asian team members, but I am the only black man, and have been in every place I have worked. I very rarely encounter another black male person – sometimes there are postdoctoral students, but they are few and far between.

I am at a point in my career where I want to reach PI level, in order to be a mentor and a leader to the next generation. I love teaching and want to start engaging with people like the British black academics, and teaching groups where there are more opportunities to mentor.

What do you think can be done to change this imbalance?

It is important for young BAME students to see role models as early in life as possible. I want to start programmes that engage them earlier, offer mentoring and introduce them to role models like them, as early as possible.

Many black families who have had senior generations encounter prejudice, preach that you must persevere and you will get a chance to show what you can do. My family was definitely one of those. However, there are a few that sometimes say that certain roles are not for us, and that if you try you will face discrimination. These are in the minority, but it does happen and is very damaging. I want people to see what I am doing, how I am doing it, and see that it isn’t not worthwhile.

What do awareness activities like Black History Month mean to you?

I’ve been really happy to see the University getting more involved in this. People take notice of Oxford, and, from my stand point, the more the University does, it can only be better for everybody.

There are lots of awareness activities throughout the year, a day here, a week here, and I am really glad that it’s a month. Right now we have to do this though, because we have to make people proud. But, you want to reach a stage where dedicating a month to it doesn’t make sense. Why limit it? Let’s celebrate all cultures, all year round.

Are there any things that Oxford as an institution could do to be more inclusive?

Athena Swan was first introduced to create parity in the field for women – as it should be. But, the equivalent (the Race equality Charter) and its awards have far less of a song and dance made about it. I would like to see more effort in this area.

I’m not saying that 50% of professors at Oxford should be black – that would be disproportionate, but there is a disparity between the number of BAME in Britain, and the numbers that enter University, and even more so the attrition of those doing STEM subjects at degree to those doing PhD or higher. It needs to be something that is spoken about more openly, more often and more loudly without shame and actively changed.

If it isn’t, then instead of waiting for it to be the general consensus, why not start the trend here? You’re Oxford. If you are going to use your clout for something, this would be great place to start.

Access in higher education is a very topical issue at the moment, do you have any ideas on what could improve the sector for BAME students

It’s important to keep the dialogue going and make your voice heard. The dialogue for our generation has to be, we need more senior black and Asian scientists.

Image credit: OUDayne is a passionate advocate for the power of mentoring, and is keen to work with young BAME pupils, introducing them to academic role models that they can relate to early on in life. Image credit: OU

I was reading about how ‘Stormzy effect’ is driving Cambridge access progress, which is a great message overall. But, it is not tenable to do this across the board. That’s why I am so passionate about encouraging BAME students in academia and doing so from an early age. The more of us there are, the more we can show that we are just as capable as anyone else. Over time there will be a generational shift, and people will just focus on the science, not the colour of your skin.

Has prejudice been a factor in your career?

I have encountered certain prejudices in my career – not at Oxford, but it has happened. People have made flippant comments about my benefiting from positive discrimination, things that shouldn’t be said to me, or to anyone in this decade.

As a black academic, sometimes when you talk about your experiences you get shot down for being over the top, or ‘always’ going on about race. When in actuality, it is the first time you have said anything.

Just because people cannot imagine it, or have not had that experience themselves, does not mean it doesn’t exist. It is a real thing.

Does this experience impact your approach to your work?

My colleagues and friends, would never expect anything less of me because of the colour of my skin. But I am sure there are people that do. I have been told in the street to go home, so I know they exist. I would be remiss if I didn’t have that consideration in my mind to try and change that, so the next generation don’t have to.

Andy Murray openly says that he doesn’t think of Serena Williams as anything more than a great tennis player, and a peer, rather than a female tennis player. That is the stage we have to get to. The task and achievement are the thing that is focussed on, not the gender or the race of the person doing it. It is something that can only come from the previous generation’s battle and fighting for that.

Have these experiences affected you personally?

I would be lying if I said no. Perception and bias are something that we are all prone to. If someone looks at me and makes an assumption, I probably do the same thing. But it is something we have to be aware of and try to make the change.

As a BAME individual you never know if people negatively respond to the colour of your skin, unless they outright say it, but I actively think about how I appear to others.

What motivates you?

I can only thank my family and my mum, for driving me forward. They instilled me with the confidence to succeed which has let me get where I am today. I am their project, they are the scientists.

Some of the stories that they have are just… I’ve experienced stuff, but I have never experienced that stuff. They raised me to always work twice as hard as anyone else, because you have to expect this behaviour, like the recent football game between England and Bulgaria. At times you despair, but I’m not going to lament it.

I just want to get high enough up the chain that I can pull others over the wall with me, if I start to berate and feel sorry for myself, I am not going to get there.

What is next for you?

Currently there is no known cure for any neurodegenerative disease. There are drugs that have been complete game changers, and have helped people to better cope with their disorder for a time. But sometimes medical trials on certain groups fail, and drugs are written off too early I believe.

I want to be involved in pushing forward a dialogue between academia, pharmaceuticals and the medical community. We have to be aware that the drugs we generate may only fit a subset of patients. Just because they don’t work for one group, does not mean they won’t for another.

Image credit: OUDayne and colleagues. Image credit: OU

Plus ça change: pharmaceutical spending in the NHS

Liz Morrell, Senior Researcher at the Health Economics Research Centre (HERC), Nuffield Department of Population Health (NDPH).

In 1957, the UK National Health Service (NHS) was just nine years old and already grappling with a very familiar problem – the rising cost of prescriptions. The drug bill at the time was £57 million, compared to the £17.4 billion spend in 2017 – clearly a different era. In June 1957, the government tasked the Committee on the Cost of Prescribing, led by Sir Henry Hinchliffe, to investigate, resulting in the Cost of Prescribing (Hinchliffe) report.

On 11 November 2019, the Health Economics Research Centre (HERC) is presenting a symposium to mark the 60th anniversary of the document. The report made a set of landmark recommendations, and the symposium will explore, 60 years on, what has changed. Do we face similar challenges today? What long-term recommendations to address the current challenges could be made by the government?

Many of the recommendations in the Hinchliffe report related to the generation, interpretation, and use of evidence on drug efficacy. These included recommendations on medical training, to include education on economical prescribing, and training to enable doctors to evaluate manufacturers’ claims for their drugs. The report accepts the importance of pharmaceutical industry investment in research and development, but wishes to curb “extravagant sales propaganda, some of which is undesirable”! Further, the report argues for establishment of a permanent expert body “to include men with business experience, an economist and a statistician” to advise on drug costs – presumably women were not invited to apply to be part of this forerunner of NICE?

As a member of the organising group for the symposium, I wanted to find out more about the discussion of the report in parliament, and delved into Hansard, the official record of UK Parliament proceedings. Surprisingly, given the subsequent impact of the report’s ideas, there is little mention of it. The report is mentioned in a debate on prescription charges on 13 July 1959, in which the Minister of Health, Derek Walker-Smith, describes the report as “a factor to be taken into account in the consideration of the relevant circumstances to which I then referred” – hardly a ringing endorsement.

The report then resurfaces two days later, in a speech by Dr Edith Summerskill (Labour), then MP for Warrington. Dr Summerskill spoke for 45 minutes on a range of health issues, suggesting that the government had been dragging its feet in responding to not only the Hinchliffe report, but two others – the Cranbrook report on pregnancy and childbirth, and the Younghusband report on social work. She is rewarded for her efforts by a response from Walker-Smith that begins with an expression of sexism that I hope would now be career limiting, by quoting from Dr Johnson: 'A woman's preaching is like a dog's walking on his hinder legs. It is not done well; but you are surprised to find it done at all.'

It is the breadth of Dr Summerskill’s speech, and not her gender, that deserves further exploration. The first issue she addresses is drug company profits, and their marketing activities, calling to mind the recent US settlements on opioid addiction, and headlines on ‘price gouging’ by the industry. She then moves to the prescription charge, which was introduced in 1952 by the Conservative government despite opposition from Labour. As removing prescription charges was an early act of devolved government in Scotland and Wales, clearly we have still not resolved this issue.

As the speech continues, Dr Summerskill moves to provision of free drugs for private patients; this debate on the somewhat uneasy relationship between private and public healthcare is a forerunner of the ‘top-up’ payments debates of 2008. In the remaining 30 minutes, she proceeds to cover antibiotic resistance, the integration of health and social care, the underfunding of mental health services, improving the safety of maternity care, and air pollution. If it were not for the occasional sexist language, it would be almost impossible to distinguish the debate from today.

Overall, then, the context for the debate on drug costs appears to have changed little in 60 years, so an examination of the Hinchliffe report and its relevance for today is timely. Speakers will come from the NHS, NICE, the Institute for Fiscal Studies, the Office of Health Economics, and the universities of Oxford, York and Bournemouth.

I leave the final words to Dr Summerskill, as she reprimands the Minister of Health for the quality of his response: 'Is the Minister aware that he has not answered one of my questions?'

Perhaps we can do better at the Symposium.

The symposium on the Hinchliffe report takes place on Monday 11 November, at Merton College, 9:30-17:00. Further details and information on registration can be found on the HERC website.

image credit: Tanesha Allen

Black female scientists have historically borne the brunt of both racial and gender biases in their fields, and in a white male dominated industry like the sciences, their achievements can at times go unsung.

These adverse circumstances make their victories all the more significant, and their contributions to the scientific community invaluable.

In celebration of Black History Month we are shining a light on some of the brilliant black minds of Oxford whose research is helping to improve the world today.

'I had never seen any prominent women of colour in zoology until I joined twitter'

Tanesha Allen, an African American Zoologist and behavioural ecologist at the Wildlife Research Conservation Unit (WildCRU), Oxford University, discusses her research studying the behaviours of European badgers, transatlantic culture shock and how and her experience as a black female scientist compares to others in her field.

Earlier this year Tanesha was awarded ‘Highly Commended’ at the Vice-Chancellor’s Public Engagement with Research Awards for her community outreach work, encouraging girls aged 11-14 to choose a career in science.

What is your research area?

I study olfactory communications in European badgers. That basically means understanding how these animals use scent to advertise themselves for mating opportunities. An animal’s scent can tell you a lot of information about them, from their age through to the group that they are from.

I started my DPhil at Oxford University in October 2016, and am I’m now in my fourth year of working with WildCRU and am part of the Wytham Woods Badger Project, which has been running since 1987.

Image credit: WildCRUTanesha Allen, is a Zoologist and behavioural ecologist at the Wildlife Research Conservation Unit (WildCRU), Oxford University. Image credit: WildCRU

Wytham Woods has the highest population of badgers in the world – 250 total, including 200 adults and 50 cubs.  Each season we spend two weeks live tracking the badgers, using a unique tattoo which they have on their inner thigh. We use this to gather information on their weight, body condition, teeth, wounds and scars etc., to see how they change over time. It helps us to understand their movements, and how these animals respond to the challenges that they face, such as changing habitats, and how we can best protect them. Understanding their movements and behaviours can also help us to prevent the spread of tuberculosis (TB).

What is a badger fact that people would be surprised to know?

Badgers are naturally promiscuous, and mate with everyone. Females have something called superfetation, which allows them to mate with, and have their embryos fertilised by multiple males.

What is a typical day in the life like for you?

There is no such thing as an average day for me.  My daily routine changes from season to season. During one season I could be spending all day in the woods collecting samples, at another time I’ll be releasing badgers back to their sets, and at others, I spend all day in my office reading journal articles. Another big part of my work is public engagement, so I spend a lot of time in schools with children running workshops to try and engage them with wildlife and conservation.

You were recently awarded “Highly Commended” at the Vice-Chancellor’s Public Engagement with Research Awards for your citizen science project with local schools. Firstly congratulations! Secondly, what interests you most about working with young people?

I love working with students, and how open they are to learning.

Usually in outreach with adults they often already have preconceived ideas about what science is and what they believe should be done, or shouldn’t be done. But with students they don’t have any preconceived notions. Just an eager thirst for knowledge.

Image credit: WildCRUTanesha works with the Abingdon Science Partnership and Science Oxford on a project encouraging girls aged between the ages of 11 and 14 to choose careers in science.

Can you tell us about your project?

I work with the Abingdon Science Partnership and Science Oxford on a project encouraging girls aged between the ages of 11 and 14 to choose careers in STEM, especially physics. I volunteered initially, and over time have got more and more involved in science outreach and communications.

Our work is funded by the Royal Society Partnership Grant, and we work with local secondary and primary schools, teaching students how to use camera traps to monitor wildlife, analyse footage and also animal behaviour. The project has been running for just over a year.

I’m also teaching them how badgers react to scent from different species and have taken them out badger tracking. We have found nine badges and six cubs so far.

Image credit: Tanesha AllenImage credit: Tanesha Allen

Tanesha's research focuses on factory communications in European badgers and understanding how they use scent to advertise themselves for mating opportunities. 

Did anyone ever try to discourage you from pursuing a career in science?

The opposite actually, I never encountered any push-back, I was always an academic person who got good grades at school, so people were very encouraging to me.  

I did encounter some challenges during my Undergraduate Degree at Washington State University. I think that was when I became more aware of social issues such as, racism and sexism and how they affect me. I went to a very diverse elementary school, and then moved to the suburbs, which were not as diverse, but I was definitely sheltered from some harsh realities like that.

Can you elaborate?

I became more aware of what it meant to be a black woman in society when I went to university.

When I started my degree I became more aware of what microaggressions were, and how people from marginalised groups are treated compared to more privileged groups.

I was one of two black women on an animal sciences course, surrounded by a lot of white students and professors, and I became aware of a number of microaggressions. There was always an assumption I was lazy or unmotivated. It was very hard and it really got to me.

Mostly because I had not encountered anything like that before in my life.

How did this experience affect you, and how did you learn to overcome it?

It was hard, and is something that I still wrestle with now. But I have learned to focus on what I bring to the table. I know my worth and the value of my research. I won’t allow someone to make me feel that way again – but it is not easy.

As a black female zoologist what does Black History Month mean to you?

In my opinion, Black History Month is an important time for everyone - regardless of their race - because, black history is a part of history. Period. Both in the US and UK, black people have had a huge impact on the development of these countries and certain social movements have influenced the trajectory of those countries, in ways that influence society at large, not just one group of people.

Black History Month is an opportunity to highlight the achievements that the black community has made in spite of the obstacles put in our way, while highlighting that more needs to be done – especially somewhere like Oxford.

On a personal level I enjoy hearing other people’s stories and connecting with others in the field. I had never seen any prominent women of colour in zoology until I joined twitter last year. But being active on social media has allowed me to connect with other women of colour in the field who share my passion for zoology, and to celebrate them more.

What is it like to work side by side a conservation icon like Professor David Macdonald?

It is amazing working with David. The year before I applied to Oxford University, Cecil the lion died and it was major news everywhere, including America, where I am from.

What gets you out of bed in the morning?

I enjoy mastering a puzzle, and putting the pieces together of figuring out how animals communicate with each other. What affects their interactions with each other, their environment and with us? I want to know how we can use their behaviour to help improve the environment.

Have you always had an interest in conservation and wildlife?

I was always interested in science as a child.

I was born and raised in Tacoma, Washington, USA, and remember going outside a lot, and spending time in my apartment complex. I loved playing with bugs and watching my neighbours dogs and birds. But, the only jobs I knew of that involved working with animals were being a vet or a zookeeper. I didn’t have much knowledge of other animal related jobs.

Animal behaviour in general has always fascinated me, particularly how similarities to humans and how they choose mates. A lot goes into that decision – who you have already mated with, who you are related to. Humans do the same thing.

How did you find moving from the US to the UK for your graduate studies and PhD work, was it hard to adjust to a new environment?

I’ve been in the UK since 2012, and the transition from my education in America, to here, has been interesting. The main thing for me was adjusting to cultural differences. Americans are more outgoing and forthright. I find it can be hard to know if you have offended a Brit, because they don’t often tell you directly.

Was your experience as a black women in science different in the UK to your American university?

There were good and bad elements to both experiences, and I have experienced discrimination in both countries in different ways.

What do you think needs to change to eliminate these behaviours?

We tend to talk a lot about sexism in STEM, but there is not a lot of talk about how different women from different types of backgrounds encounter different challenges in STEM. So there is not a lot of focus on intersectionality. I think one good step would be addressing unconscious bias. As scientists we are trained to be objective and logical. Often there are times we think we don’t have unconscious biases with social issues, or towards certain groups of people, but we do. I think having our unconscious biases addressed, and unlearning our own behaviours would be a good way to make things easier for the next generation of women and women of colour in

Image credit: WildCRUImage Credit: WildCRU

Tanesha and her team in Wytham Woods

During my second and third year at Oxford I was the postgraduate representative for the Oxford University Campaign for Racial Awareness and Equality, which allowed me to push forward ideas around conducting racial awareness workshops on a college and department level. Postgraduate students are more connected to their departments than their colleges so it is important to consider both areas.

Is there anything that you would change about the University?

There is a lot I would change about how marginalised, and under-represented groups are treated in Oxford.

There are definitely more initiatives in place that are helping to improve diversity, and encourage more people of ethnic minorities to apply, which is excellent. However, the next step is making sure people from these groups are included more within research grounds, colleges and wider projects.

It is one thing for institutions to be diverse, but if those people don’t feel like they are being properly valued, included and respected, these initiatives fall short.

What’s next for you when you finish at Oxford?

I am finishing my thesis and will complete my PhD next summer. I am not sure what comes next, but I hope to continue my science outreach work with children, and would love to stay in the UK.

What do you like most about being part of Oxford University?

To me the history behind it is incredible. Whenever you walk around, the tiniest things are connected to a prominent person who made a historic contribution to the University centuries ago.

Compared to the States the oldest buildings and things would be from at most the 1700s. Whenever I walk around central Oxford, and look up and see the beautiful Bodleian Libraries and Sheldonian Theatre around me it can be me it is surreal. Especially when I see the tourists walking around, taking pictures and looking in awe just to be here, it reminds me how lucky I am, and I think to myself ‘I actually live here, that’s cool!’

How do badgers respond to scents from other species?


Image credit: OU

The Africa Oxford Initiative (AfOx) is a cross-university network that brings the University of Oxford’s long-standing, multi-disciplinary engagement with Africa under one platform. The overarching goal of AfOx is to ensure Africa remains a strategic priority for the University, and that students and academics who attend from the Continent feel supported and at home while they are here.

Building networks for research leadership

The ethos of AfOx is to facilitate the development of equitable and sustainable collaborations between researchers from African institutions and from the University of Oxford.

To enable effective partnerships that are genuinely co-developed, AfOx offers two researcher mobility schemes- the AfOx Visiting Fellowship Program and the AfOx Travel Grant. 

AfOx Travel Grants are open to all disciplines and support the establishment of new collaborations between researchers based in African research institutions and at the University of Oxford. The Travel Grant is a flexible fund which covers research and travel costs in either direction i.e. from University of Oxford to an institution in an African country or vice versa.

Since 2016, AfOx has awarded over 165 travel grants that have facilitated new collaborations between 46 departments within the University of Oxford and 90 African institutions across 30 countries.

The AfOx Visiting Fellowships Program enhances academic mobility and network building by supporting leading African scholars and researchers to spend periods of flexible time in Oxford, utilising the University’s facilities and undertaking collaborative research with Oxford based colleagues. This summer 20 researchers from 12 African countries visited Oxford as part of the AfOx Visiting Fellows Program.

AfOx collaborations seek new breakthroughs in the fields of medical sciences, big data engineering and astrophysics, conserving environments and ecosystems, archaeology, preservation of ancient languages amongst other research areas.

Supporting student experiences in Oxford

In support of students, and in partnerships with the Oxford University Africa Society, AfOx runs academic support programs to enhance the graduate experience at Oxford, promote a sense of belonging and enhance the academic success of emerging African leaders in Oxford. These targeted programs include essay writing workshops and tips on pursuing DPhils in Oxford. AfOx also hosts an annual online admissions open day for prospective African graduate applicants.

Africa-focused conversations 

Throughout the year, AfOx hosts engaging conversations on Africa related issues. One of the most popular events is the AfOx insaka. This is a gathering for sharing ideas and knowledge about Africa-focussed research. Experts from varied disciplines and academic background present their work and ideas, followed by opportunities for discussions and networking.

Hosted twice a term at St Cross College, the AfOx insakas feature talks on diverse issues from the fourth industrial revolution and marine ecology and conservation to radio astronomy – among others.



The evolution of antibiotic resistance

Craig MacLean, Professor of Evolution and Microbiology at Oxford's Department of Zoology, explains how evolutionary biology can help us to get rid of antibiotic resistant bacteria.

Bacteria are tiny single cell organisms, invisible to the naked eye, that live in essentially every possible habitat on our planet. Plants and animals are covered with microorganisms, the soil and the oceans are teeming with bacteria, and it is estimated that bacterial cells actually outnumber human cells in the body by a factor of 10-100:1. The overwhelming majority of bacteria are completely harmless, but a small minority of pathogenic bacteria can cause infections in humans. For most of human history, bacterial pathogens have been a major cause of disease and mortality. For example, the plagues that ravaged Europe in the middle ages were caused by the bacterium Yersinia pestis, and tuberculosis, and cholera outbreaks are caused by the bacterium Vibrio cholera.

The development of antibiotics in the 1940s provided a simple and effective treatment for many bacterial infections; for example, antibiotics decreased the mortality rate associated with serious cases of pneumonia from 90% to 10%. Given these stunning results, many prominent members of the medical community, including the US Surgeon General, thought that antibiotics would effectively make bacterial disease a thing of the past. Against this background of boundless optimism, researchers had already discovered that bacteria could become resistant to antibiotics and Alexander Fleming, who led the team that discovered penicillin, warned that the misuse of antibiotics would lead to the rise of resistance, rendering antibiotics ineffective.

Antibiotics have now saved millions of lives, but the large-scale use of antibiotics has driven the spread of resistance, as predicted by Fleming. Pathogenic bacteria have evolved resistance to all of the main classes of antibiotics and pan resistant bacteria have caused untreatable infections. Resistance already imposes a substantial health and economic burden, and an influential report published by the O’Neill commission in 2016 predicted that resistant infections could cause 10 million deaths per year and impose a global financial cost of 100 Trillion USD by 2050. Given this threat, resistance has been identified as one of the most important global challenges by organisations such as the United Nations, the G8 and even the International Monetary Fund.

The spread of antibiotic resistance in pathogenic bacteria is a simple and elegant example of evolutionary adaptation by natural selection. Bacteria can become resistant to antibiotics through mutations that alter the cellular targets of antibiotics or by acquiring dedicated resistance genes from other bacteria. The acquisition of resistance is a very rare event; for example, resistance mutations usually occur in less than 1 in a million bacteria. However, resistant bacteria can continue to grow and reproduce under antibiotic treatments that effectively paralyse or kill their antibiotic susceptible neighbours – this is Darwinian natural selection in its simplest and cruellest form. Rare resistant strains can rapidly come to dominate pathogen populations under antibiotic treatment, and, in a worst-case scenario, these resistant bacteria can then go on to infect other people.

This simple sketch shows how evolution drives the spread of resistance, but it leaves out many important details. Evolutionary biologists and microbiologists have become increasingly interested in understanding the processes driving the spread and maintenance of resistance. These studies have addressed a wide-range of important questions, such as: What limits the transmission of resistant bacteria between people? How does the strength of antibiotic treatment influence the likelihood of resistance emerging? Can antibiotic cocktails be used to suppress the evolutionary advantage of resistance? How do resistance genes move between bacteria? We now have quite a mature theoretical framework for thinking about these important questions. The problem, however, is that the largely theoretical approach the evolutionary biologists have taken to resistance is not very well connected to the reality of resistance in the clinic.

In the last 15 years, technological innovations have massively improved our ability to sequence the genetic code of all living organisms, especially bacteria. Sequencing the genomes of pathogenic bacteria isolated from infections has provided a much clearer picture of how resistance emerges and spreads, especially in hospitals. In many important human pathogens, the global increase in the prevalence of antibiotic resistance has been driven by the epidemic spread of a relatively small number of highly resistant ‘superbugs’ that transmit between people, such as MRSA Staphylococcus aureus and XDR Mycobacterium tuberculosis. If evolutionary biology is going to help contribute to stopping the spread of antibiotic resistance, the field is going to need to shift emphasis towards understanding the specific processes that have driven the emergence of the superbugs.

For more information, read: 'The evolution of antibiotic resistance' in Science.