Peter Gluckman

Professor Sir Peter Gluckman - A Good Start In Life

Professor Sir Peter Gluckman has an impressive list of honours. Most New Zealanders will know him as the inaugural Chief Science Advisor to the Prime Minister, appointed to the position in 2009. He is also a Professor of Paediatric and Perinatal Biology and past director of the National Research Centre for Growth and Development at the University of Auckland, and was co-founding Director of the Liggins Institute.

Among numerous other honours, he is the only New Zealander elected to the Institute of Medicine of the United States National Academies of Science, and is a Fellow of the Academy of Medical Sciences of Great Britain. He is a Fellow of the Royal Society of London, an honour bestowed on just 37 New Zealand-born scientists since the Society's establishment in 1660, and in 2001 he received New Zealand's top science award, the Rutherford Medal.

Sir Peter started out as a paediatric endocrinologist and quickly discovered that he preferred research to clinical work. He began investigating growth regulation of the foetus and for many years his research has focused on how the in utero environment, and the choices a mother makes during her pregnancy, go on to influence her child's health later in life. In his biographical note, on the Office of the Prime Minister's Science Advisory Committee website, he talks about "one of the major issues in biology and medicine - how does a poor start to life impact on health and disease risk throughout life?"

"I'm passionate about a healthy start in life," he tells me by phone. "People grossly underestimate the importance of a good start in life."

And by that he means ensuring that a baby's environment between conception and birth is as good as possible, because his research has shown that this determines a baby's childhood development and life-long health.

A brief perusal of the titles of his medical and scientific papers - of which there are more than 500 - reveals that most of his research into the impact of in utero influences on subsequent health is in the area of metabolic syndrome, obesity, cardiovascular disease and diabetes. Although he admits to "not being an expert on breast cancer" he is no slouch either. I guess that is why, as Chief Science Advisor to the Prime Minister, he is in position to comment and advise on topics as far-reaching as climate change, adolescent morbidity, the Canterbury earthquakes, and biosecurity; he is first and foremost a scientist and puts that analytical ability to work on many aspects of science and medicine.

The problem with breast cancer, he says, is that we don't know very much for certain about the causes although there is some suggestive epidemiological evidence. He mentions Dr Karin Michels' work and says that we know that large babies go on to have a higher risk of breast cancer, but we don't know why. Is it the growth factors that drive the subsequent development of this disease?

"It is important that we gain an understanding of the early life influences, of how breast tissue develops in utero," Sir Peter says. He goes on to talk about the possibility that the way that ductal tissue develops - the bifurcation or branching of the ducts - may influence the risk of breast cancer later on. It is where the ducts branch that DCIS is more likely to occur, so there may be something about the way in which this process happens in utero that is important.

Then there is the issue of chemical exposures in utero, in particular oestrogenic chemicals such as bisphenol A and phthalates. He refers to the work done by researchers such as Dr Ana Soto and her colleagues, but points out that there are significant limitations with the work that has been done on rodents. After all, mice are not people, and the results of this work are difficult to sort out; are the effects that we see causal or temporal?

It is clear that we don't yet have definitive proof that these chemicals contribute to breast cancer, and Sir Peter is wary of suggesting that there is any causation. So, I ask where we go from here; what needs to be done?

He provides the standard and wholly expected answer that more detailed studies need to be undertaken.

"Possibly in non-human primates," he says, "to see if there are changes in the development of breast tissue. We really need to move on from rodents."

"And we need to collect more breast tissue samples. It is very difficult without more data."

His comments hark back to my interview with Dr Susan Love in 2007, when I was blown away by how much we simply don't know about the development of the breast. It seems we don't know very much more, almost five years down the track.

Sir Peter points out that breast cancer is multi-factorial, and that it is influenced by women's reproductive behaviour as well as the environment. He believes it is asking too much of the science to actually find out for sure.

"We could design the methodology," he says. "But it is always the practicalities that get in the way - we can model it but we can't really test the model."

It comes down to ethics. After all, which women would put their hands up to be the "guinea pigs" and allow someone to actually try to cause them to develop breast cancer?

We move on to lifestyle changes that might reduce risk. Sir Peter believes that the IARC (International Agency for Research on Cancer) claim that we could cut cancer incidence by a third if everyone stopped smoking and another third if everyone got enough exercise, reduced their alcohol consumption, ate a more Mediterranean diet and maintained a healthy body weight, is somewhat overstated.

He says that the presumption is there, but we don't know for sure; we don't know what the magnitude of the effect is. He wouldn't use cancer reduction as the reason to make such changes, and talks about the cost and that there has to be justification for such actions. However, it seems to me that there can only be benefits from such lifestyle changes.

However, his equivocation on this can surely be forgiven in light of his strong endorsement of breast feeding as something that reduces the risk of breast cancer.

"By breastfeeding there is clearly a beneficial effect for the mother, on top of all the benefits for the baby," he says.

Towards the end of my interview with Sir Peter, he says that breast cancer is largely a modern phenomenon, which seems rather ironic to me, as all the modern science in the world isn't able to work out quite what it is about modern life that plagues so many of our women. So I'd best not take up any more of his time and leave him (and his colleagues around the world) to get back to working out just where life in the womb fits in to the puzzle.