In the early nineties, more than 14,000 pregnant women enrolled into ALSPAC, the Avon Longitudinal Study of Parents and Children – known to its friends as ‘Children of the 90s’. Every year for over two decades, these parents and children have provided all kinds of information to researchers to create a dataset unique in the world. Combining hundreds of different elements, including biological samples, environmental measures, clinical assessments, and key life events, it’s an astoundingly detailed picture of human development which continues to yield surprises. Professor Jean Golding OBE, who founded the study, says of her unprecedented project:
“When we started ALSPAC, they asked why we collected so many participants. Later, they asked why we collected so few!”
Professor Golding had to convince funders, scientists, and other epidemiologists of the benefits of a broad approach with open-ended questions, rather than the focused approach favoured at the time. When asked how she was able to push through these concepts in the face of critics, she says lightly: “Oh, they thought I was mad for at least 20 years – it made me more determined!” She mentions notable support from the vice-chancellor of the University of Bristol at the time, who was a mathematician and statistician, and “really got it”.
The study participants, on the other hand, she says, ‘understood it all, and really bought into it’. Jean explained to the cohort their aims – “We were going to look with fresh eyes, on the basis that we actually didn’t know what were the appropriate ways to make children healthy” – and asked for their contribution to this joint effort.
This is an activity that of course requires trust, and imposes a duty on the researchers towards the participants. Jean says: “I think you have to be extremely careful. As long as the study parents and participants trust you – that is a burden, you have got to get it right. If they don’t trust you, you have to get it right too, but it’s not so damaging. If they lose trust in you, they lose trust in the future. That would be really disastrous.”
Some of her understanding of the participants’ concerns come from her own experience. Her own grandson, born, conveniently, two years before the start of the study, was used as a ‘guinea pig’ for some of the assessments which ALSPAC families would complete.
In a novel approach, ALSPAC carers and babies were asked to report their lives and habits, such as smoking, and also to undergo assessments, such as language ability, and to give biological samples. The last two elements were made at the suggestion of Professor Golding’s long-term collaborator, Professor Marcus Pembrey (also of the University of Bristol), who Golding says made sure the right data was collected at the right times. This has enabled geneticists to use the dataset to look at how the genetic code changes in response to environmental conditions – showing the prescience of the study, since the samples were stored long before the technology to examine this information efficiently existed. Jean describes this modestly as another example of her “picking up people’s ideas and putting them into practice.”
Data collected on the ‘Children of the Nineties’ includes such categories as (chosen at random as an illustration): physical activity levels of children, blood samples from everyone, IQ scores, dietary reports, 3D face scans, ball skills, the number of days pubescent girls experienced menstrual cramps, measure of air pollution exposure in year-old babies, short term memory in four year olds, waist circumference, the smoking habits of the ALSPAC mothers’ mothers, and amount of screen-time for the grandchildren of the original pregnant participants (the children of children of the 90s, or COCO90s). It’s a dizzying amount of data.
The ALSPAC findings have yielded over 1,500 publications so far, on topics ranging from the increased risk of obesity in children whose grandparents smoked, the relationship between lead levels in blood and SAT results, to the non-correlation of cat ownership with psychosis[could substitute if wanted]. However, many relationships remain to be explored.
Jean is currently particularly interested in early pregnancy and how that affects the child and its development into early adulthood. She describes with engagement an illustrative issue; the benefits of seafood for the developing brain weighed against concerns around the accumulation of heavy metals. With access to information about trace metals in the blood, the diet of a pregnant mother and her child, and the child’s developmental progress, the epidemiological team at ALSPAC have the pieces to make a recommendation. Jean’s analyses, with colleagues, suggest that there are no harmful effects from mercury if the mother eats fish, while if she doesn’t eat fish, there is some indication that there is harm to the child.
However, translating these findings into policy proves difficult, and current advice on this one issue lags behind the latest work. I ask if she has any ideas for improving uptake of such research outputs, and she replies cheerfully: “All we can do is batter away!” Cod (or a non-endangered alternative) and chips all round, then.
Current work for Professor Golding includes ongoing work with the geneticist, Professor Pembrey, looking at transgenerational effects – not just in the genome, the sum of the DNA information in an individual, but the epigenome, the DNA and the chemical changes modifying how it interacts. Their work so far shows that the habits, such as smoking, in the mothers of the cohort pregnant in ‘91 affect the adolescence of their babies – that is, the habits of the grandmothers are visited upon their grandchildren. In this case, the team have identified various effects including associations with obesity and cognition.
In the future, Professor Golding is excited about looking into the effects of stress on development through the generations, perhaps from historical tragedies such as famine or personal ones such as bereavement. Another interesting possibility is to extend the study a generation further, since some of the children from the original cohort are having children. But given that not all the cohort are taking that step, another option is linking through older records to consider the life histories of great-grandparents of the contributors. Could it be possible to see traces of a childhood in the 1930s workhouse in their 21st century great-grandchild?
There seems to be no end to the data that can be collected about a human life, or the questions that can be asked about it. Interviews with participants reveal that, on the whole, they were happy to contribute all sorts of personal information, and contribute their time, as long as the data is used. From the moment I meet her, Jean is clear that her job is to make sure that the efforts of the participants of the ALSPAC study, their children, and now grandchildren, are used to fulfil her promise to them two decades ago: to find out how to make people more healthy.
Find out more about Professor Jean Golding’s career, and her tips for a successful collaboration and data investigation, in the first blogpost in this series. Written by Kate Oliver, PhD student at the University of Bristol and freelance science writer. With thanks to Professor Jean Golding for a fascinating conversation!