Wellcome Trust Research Round-Up: 08.01.16
Our fortnightly round-up of news from the Wellcome Trust community…
Calling the shots
A Hib booster is not necessary for toddlers to extend immunity into later childhood, according to new research carried out at the KEMRI-Wellcome Research Programme in Kilifi, Kenya.
The 15 year study confirms that the spread and infection of the bacteria Haemophilus influenza type b (Hib) – which causes life-threatening infections such as meningitis, sepisis and pneumonia – is under control in Kenya.
The research, published in Lancet Global Health, suggests that bacteria in the environment similar to Hib may provide a natural boost to the immune system, even though the Hib bacterium has stopped circulating in the community.
While most high-income countries offer an additional booster dose of the Hib vaccine, Kenya has followed the World Health Organization’s regime of no booster dose.
Between 2000 and 2014, researchers funded by the Wellcome Trust and Gavi, the vaccine alliance analysed blood samples from over 38,000 children. They found that the vaccine reduced the chances of Hib by 93%.
The researchers also identified that eight years after the vaccine was introduced, 79% of children in the disease risk group (4-35 months) had antibodies at levels indicating long-lasting protection.
Dr Charlie Weller, Vaccine Strategy Lead at the Wellcome Trust, said: “The Hib vaccine is a public health success story for Kenya and a powerful example of the positive impact that long term vaccination programmes can have on the health of a population. By evaluating the vaccine over a long period, the researchers have highlighted that children can have slightly different levels of response to the same vaccine in different countries. We can now use this data to inform the most appropriate vaccine schedule for each country.”
Who do you think you are?
Ancient DNA have revealed that approximately a third of British ancestors were Anglo-Saxon migrants, according to new research published in Nature Communications.
Researchers analysed ancient skeletons, comparing their genomes to modern-day sequences using a new analysis method. They found that Anglo-Saxon migrants were genetically very similar to modern Dutch and Danish, and contribute a significant proportion to the DNA of modern British people.
The skeletons were excavated from burial sites near Cambridge and have been carbon dated, proving they were from the late Iron Age (approximately 50BC) and the Anglo-Saxon era (500-700 AD).
While previous DNA studies – which relied entirely on modern DNA – suggested Anglo-Saxons contribute anything between 10 per cent and 95 per cent to the population, this new technique proves how integrated the people of Britain were.
To accurately distinguish between the genomes of northern European populations, researchers developed a sensitive new method called rarecoal, which can identify subtle genetic traces in individuals using rare genetic variants identified in hundreds of present-day people.
Dr Stephan Schiffels, first author from the Wellcome Trust Sanger Institute, Cambridgeshire and the Max Plank Institute in Germany, said: “By sequencing the DNA from ten skeletons from the late Iron Age and the Anglo-Saxon period, we obtained the first complete ancient genomes from Great Britain. Comparing these ancient genomes with sequences of hundreds of modern European genomes, we estimate that 38 per cent of the ancestors of the English were Anglo-Saxons. This is the first direct estimate of the impact of immigration into Britain from the 5th to 7th Centuries AD and the traces left in modern England.”
Using painkillers in pregnancy could reduce fertility in the next generations, Wellcome Trust-funded research suggests.
The study, conducted in rats, found that when a mother was given painkillers during pregnancy her female offspring had fewer eggs, smaller ovaries and smaller litters of babies compared to those not exposed to the drugs.
Although it is difficult to extrapolate these results to pregnant women, researchers suggest that the similarities between reproductive systems of humans and rats make these findings significant.
Two painkillers were tested in pregnant rats – paracetamol and indomethacin (a prescription-only drug in the same class as ibuprofen and aspirin).
Scientists found that subsequent generations of rats were also impacted by painkillers taken in pregnancy, with females having altered reproductive function.
It is thought that some painkillers might affect the development of germ cells (the cells that create eggs and sperm) while a foetus is in the womb.
Professor Richard Anderson, Elsie Inglis Professor of Clinical Reproductive Science, who co-led the study published in Scientific Reports, said: “These studies involved the use of painkillers over a relatively long period. We now need to explore whether a shorter dose would have a similar effect, and how this information can be usefully translated to human use.”
In other news…
Last week, the World Health Organization declared the Zika virus is a public health emergency of international concern, due to its probable link with microcephaly. We’ve posted an explainer about the disease, and how the Wellcome Trust is working with partners in this area.
The Human Fertilisation and Embryology Authority (HFEA) in the UK approved a research application for new gene editing techniques on human embryos. The research will be led by Dr Kathy Niakan at the Wellcome Trust-funded Francis Crick Institute.
Congratulations to Wellcome Trust-funded researcher Dr Andrew Muinonen-Martin for winning a publication award by La Fondation La Roche-Posay for his work on melanoma.
Congratulations to writer and director Julian Simpson for winning the 2016 Tinniswood Award for his Wellcome Collection-inspired audio drama Fugue State.