Genetics and ethics collide at the pinnacle of sport

Most newly crowned champions take time to enjoy the moment. To soak up the atmosphere of victory, wave at the crowd and speak to the media. In August 2009, when Caster Semenya won 800m gold at the World Championships in Berlin, she headed straight for the dressing rooms.

A few hours before the race, the news had leaked that the South African runner had been asked to take a sex test. She was stronger, broader and unquestionably faster than her competitors. She was also improving at an incredible rate, having cut eight seconds off her personal best in just a year. Whispers about her sex had dogged her for years, but now they grew louder. The sport’s ruling body, the International Association of Athletics Federations (IAAF, now called World Athletics) wanted to investigate.

Despite the timing and the media circus, Semenya triumphed in that race. For her coaches and supporters, it was a celebration of the 18-year-old’s extraordinary talent. But it was a moment that also marked the start of a controversial journey through issues of sex, genetics and ethics that, ten years later, ended up in the Court of Arbitration for Sport (CAS) – where a Manchester Metropolitan University scientist gave expert testimony in her defence.

Regulating differences in sex development

Semenya’s test results will have revealed that she had a condition which gives her naturally elevated testosterone levels – one of a number of genetic conditions collectively referred to as differences in sex development (DSDs).

The IAAF spent almost a year considering these results before they cleared her to race again. In the years that followed, she won two more World Championship gold medals, two Olympic gold medals and two Commonwealth gold medals – all of them against a backdrop of shifting regulations.

In 2011, the ruling body introduced ‘hyperandrogenism’ regulations for female athletes, which were challenged, suspended and eventually scrapped. They tried again in 2018, with rules that required female athletes to have less than 5 nanomoles per litre of testosterone (compared to ‘normal’ levels somewhere between 0.12 and 1.79 nmol/L) for six months before competition. For an athlete with DSDs, complying with these regulations meant taking hormones or even getting surgery.

At the time, the IAAF president, Sebastian Coe, said: “The regulations that we are introducing are there to protect the sanctity of fair and open competition.” They claimed to have research that showed that these elevated testosterone levels could offer as much as a 3% competitive advantage.

These new rules did not apply to all athletics events. Instead, they were specifically for races between 400m and a mile – precisely the middle-distance disciplines in which Semenya had excelled. From the IAAF’s point of view, their new research applied to these events alone. Others saw too much of a coincidence. As Semenya herself put it: “I know that the IAAF’s regulations have always targeted me specifically.”

Her team disagreed with the logic of the rules, found fault with their scientific basis and had ethical concerns about the medical treatments needed to lower her testosterone to meet these rules. To make that case meant going to CAS for a ruling. And that meant that they needed experts.

From rugby drills to gene sequences

If things had been different, Dr Alun Williams might have been a rugby professional. He has the build for it, not to mention the passion. But something was missing.

“I played at a good level. I trained hard, looked after myself, ate the right things. But, while others in my club went on to make the step up, it wasn’t to be for me.” Instead, he had to settle for a role as one of the world’s foremost researchers in the genetics of elite sport. It’s quite the plan B.

Having trained as a sport scientist, he went onto a PhD, developing training programmes for the British Army. That work brought him together with a group researching the genetics of cardiovascular health, whose interests overlapped with his work on cardiovascular function in athletes – opening the door to an area that would define his career.

“Personally, I find it fascinating to think just how much of who we are is wrapped up in our genes. Our DNA determines our physical characteristics, which determine our athletic qualities and abilities – in very precise and specific ways. It makes a huge difference to sporting performance, a difference all the greater at the elite level.”

Talent, hard work and luck

‘Talent’ is a word often used to describe an elite athlete’s abilities. But it’s a slippery concept – is it an innate quality, bestowed by fate? Or is it something we can train into our muscles and minds, the result of hard work?

As Dr Williams discovered, it takes more than training to make the grade in rugby. Likewise, natural aptitude won’t take you far if you don’t practise the skills and look after your body. As he says, “Performance comes down to a 50-50 split between your genetic make-up and lifestyle factors.” Put another way, elite talent comes with a mixture of elite DNA and elite training.

While the concept of fairness is absolutely central to sport, our biology is fundamentally unequal. “Some of us have the potential to pull on a scarlet top for Wales and some of us end up in a white lab coat. Semenya had the genetic potential to run the 800m faster than her nearest competitor on the world stage.”

Dr Williams has spent 25 years investigating that genetic potential, working to identify which genes – or combinations of genes – influence various aspects of sporting ability. What is it that makes some explode out of the blocks, or leap higher, or heal faster?

Genetic Expertise at Manchester Metropolitan University

“When I first looked into the genetics of sporting performance, I found a huge gap in our understanding. Sport science was still a relatively new field, and this element was even newer. It was an undiscovered territory.”

To help Dr Williams explore this territory, he and the team at Manchester Metropolitan University have built up a store of around 2,000 DNA samples in cryogenic storage. Of course, the identity of the donors is strictly confidential, but they all come from sports people, mostly from rugby players – “household names” as he puts it. Put another way, they’ve built a library of elite genes.

Again and again, Dr Williams has delved into this library to chart the genetic characteristics of superior physical performance. “It’s an incredible resource for us to have, an opportunity to chart the vast map of genes that influences sporting performance.”

Over the years, he’s published a series of papers – identifying patterns and investigating correlations to reveal what makes these athletes superior. The genes that determine muscle mass, fast-twitch and slow-twitch fibres, blood oxygen levels, hormone production, fat mass and much more. “For coaches, doctors and athletes, it’s data that tells you about stamina on the track, strength in the tackle, resilience from injury or recovery time after a match.”

This insight could be vital for recruiting players, improving performance, preventing and treating injuries, and more. But it also sheds light on just how different elite athletes are compared to the rest of us – showing the exceptional combination of exceptional genes it takes to reach the top.

People in elite sport – including the administrators – are well versed in the lifestyle factors of performance. They understand how training and nutrition can relate to the time an athlete posts at the finishing line, the distance they throw or the tries they score. The genetic component is less understood.

In a sense, there are few people in the world who better understand what really constitutes an elite athlete than Dr Williams – which gives him a powerful voice in the debate around the impact of DSDs.

Called to Switzerland

As the highest court in international sport, CAS has heard many high-profile cases – from state-sponsored doping to financial fair play. Yet Caster Semenya’s case was one of the most contentious – a moral dilemma that pitted sporting competition against human rights. It was even dubbed the ‘Sporting Trial of the Century’ by some in the media.

To make Semenya’s case and challenge the scientific basis of the IAAF regulations, her legal team assembled a group of experts. Enter Dr Williams. As well as producing a comprehensive written submission stretching to more than 80 pages, he left Manchester Metropolitan University and flew to Lausanne, Switzerland to testify. Over the course of four days, he gave his evidence and was cross-examined. “While it was an intimidating setting, I was actually pleased to have the chance to lay out what I considered to be a compelling argument.”

First, there is the focus on testosterone. Some DSDs may result in higher levels of the hormone, without it being properly processed – without gaining the advantage a test suggests. For most, the hormone boosts haemoglobin levels, muscle mass and skeletal development. Removing or inhibiting that testosterone will, over time, reduce the blood’s ability to move oxygen to the muscles and it will partly diminish those muscles, but it won’t shrink the bones. “There’s no question that naturally occurring testosterone offers some advantage in performance. Quantifying that advantage is difficult. Reversing that advantage is, I think, unethical – if not impossible.”

Whatever the conclusions about testosterone levels, it seemed they were also built on shaky foundations, as serious doubts were raised about the IAAF’s research – with anomalies or errors in their data sets.

Second, there’s the question of what sex really is – how the definition between male and female is not as clear as it can seem. By setting an ‘acceptable’ level of testosterone for female competitors, the IAAF was attempting to draw a clear line between the two sexes. As Dr Williams testified, it’s just not that simple. “I referred to the World Health Organization that clearly states no single biological factor, genetic or otherwise, neatly determines whether an individual is male or female.”

Finally, there is this idea of ‘unfair’ advantage. Dr Williams has spent his career investigating the very precise genetic reasons some athletes are better equipped than others, mapping the elite performance in their genes. Some DSDs might offer a 10% edge over people without them, a huge advantage. But, as Dr Williams outlined in his testimony, if you tally all the advantages that most elites enjoy – the fast-twitch fibres, blood oxygen levels and all the rest – it could add up to even more. “There is no qualitative difference between most athletes’ genetic advantages and Caster Semenya’s DSD, yet they celebrate one and want to ban the other.”

It seemed that this particular genetic advantage was being singled out because it is wrapped up in our sense of sex, as it challenged the strict binary code that sport lives by. For women born with DSDs, the only way to fit in with that binary world was through an unnatural intervention – forcing their biology to comply. That not only carries unknown risks but is unethical from a medical perspective – a solution without a problem.

A victory without a winner

It couldn’t have been closer. The panel of three arbitrators deliberated for two months, then ruled 2 to 1 against Semenya. Not only a split decision, it was one that came with various conditions, commentary and concerns. There were questions about the practical application of the regulations and about the evidence of testosterone’s impact at 1,500m. The ruling acknowledged that the regulations are discriminatory, but said that it was a “necessary, reasonable and proportionate means” of maintaining the “integrity of female athletics”.

Much like the race in Berlin ten years earlier, the result caused a media storm – more outrage, intrusion and questions for an athlete who, as Martina Navratilova pointed out, had done nothing wrong. Afterwards, Caster Semenya said: “I am a woman and I am a world-class athlete. The IAAF will not drug me or stop me from being who I am.”

For Dr Williams, it was no doubt disappointing, but not definitive. “Obviously, I wasn’t happy with the result, but I think the caveats and concessions in the ruling, not to mention the fact it was a split decision, shows that the debate is far from over.” Both CAS and the IAAF referred to these rules as a ‘living document’ – implying there is room for evolution.

Sport exists to push boundaries – this is simply another boundary that will be pushed. In Dr Williams’ view, it won’t be long before we see similar cases challenging the definitions that sport imposes on sex. “Only time will tell whether the regulation will be permanent or challenged again.”

The next race

Beyond his work on Semenya’s case, Dr Williams’ research continues – that vast gap in our understanding of genetics is far from filled. Next up, it’s another area that’s making headlines: concussion. “It’s another subject we just don’t understand very well, so there’s a great chance to make a real difference to people’s lives.” His passion for rugby burns as brightly as ever, so that’s where he intends to start – investigating the genetic reasons that make some players more susceptible than others to injury and looking at how others recover faster than others and how, perhaps, a test can help team physios to address these diverse needs of their players.

As for the issues at the heart of the Semenya case, it’s unlikely to be the last time that issues around sex and identity conflict with the black-and-white definitions of sporting competition. Testosterone remains a key measure, but we still don’t fully understand the impact of unnaturally changing the levels of a natural hormone.

And, with society’s growing awareness of Trans rights and identity, there are certain to be ethical questions facing sport. As Dr Williams put it: “When an athlete transitions from one gender to another, how do the sporting authorities decide where the line lies between male and female sport? How many more cases will we see of fair competition versus equal rights?”