Wellcome Trust Research Round-up 09/06/14

Our fortnightly round-up up of news from the Wellcome Trust research community.

‘Map of pain’ reveals sensitivity in forehead and fingertips

“Where does it hurt?” is the first question asked of anybody in pain. A new UCL study, funded by the Wellcome Trust, defines for the first time how our ability to identify where it hurts, called “spatial acuity”, varies across the body, being most sensitive at the forehead and fingertips.

Researchers used lasers that were able to cause pain to 26 healthy volunteers without stimulating their sense of touch. From this they have produced the first systematic map of how acuity for pain is distributed across the body. The work is published in the journal Annals of Neurology.

With the exception of the hairless skin on the hands, spatial acuity improves towards the centre of the body whereas, conversely, the acuity for touch is best at the extremities. This spatial pattern was highly consistent across all participants.

The experiment was also conducted on a rare patient lacking a sense of touch, but who feels pain normally. The results for this patient were consistent with those for healthy volunteers, proving that acuity for pain does not require a functioning sense of touch.

Senior author Dr Giandomenico Iannetti said: “Touch and pain are mediated by different sensory systems. While tactile acuity has been well studied, pain acuity has been largely ignored, beyond the common textbook assertion that pain has lower acuity than touch. We found the opposite: acuity for touch and pain are actually very similar. The main difference is in their gradients across the body. For example, pain acuity across the arm is much higher at the shoulder than at the wrist, whereas the opposite is true for touch”.

‘Male’ hormones in the womb linked to autism

A new study has found that the levels of steroid hormones – for example testosterone, progesterone and cortisol – during prenatal development are, on average, elevated in children who later develop autism.

The finding may help explain why autism is more common in males than females, but should not be used to screen for the condition. The work was funded by the Medical Research Council (MRC) and the Wellcome Trust, and published in the journal Molecular Psychiatry.

The team, led by Professor Simon Baron-Cohen and Dr Michael Lombardo in Cambridge and Professor Bent Nørgaard-Pedersen in Denmark, used approximately 19,500 amniotic fluid samples stored in a Danish biobank from individuals born between 1993-1999. Amniotic fluid surrounds the baby in the womb during pregnancy and is collected when some women choose to have an amniocentesis around 15-16 weeks of pregnancy.

This coincides with a critical period for early brain development and sexual differentiation, and thus allows scientists access into this important window in fetal development. The researchers identified amniotic fluid samples from 128 males later diagnosed with an autism spectrum condition and matched these up with information from a central register of all psychiatric diagnoses in Denmark.

Professor Baron-Cohen said: “This is one of the earliest non-genetic biomarkers that has been identified in children who go on to develop autism. We previously knew that elevated prenatal testosterone is associated with slower social and language development, better attention to detail, and more autistic traits. Now, for the first time, we have also shown that these steroid hormones are elevated in children clinically diagnosed with autism. Because some of these hormones are produced in much higher quantities in males than in females, this may help us explain why autism is more common in males.”

Spider venom takes the sting out of pesticides for bees

A novel bio-pesticide created using spider venom and a plant protein has been found to be safe for honeybees – despite being highly toxic to a number of key insect pests.

New research led by Newcastle University, UK, has tested the insect-specific ‘Hv1a/GNA fusion protein bio-pesticide’ – a combination of a natural toxin from the venom of an Australian funnel web spider and snowdrop lectin.

Feeding acute and chronic doses to honeybees – beyond the levels they would ever experience in the field – the team found it had only a very slight effect on the bees’ survival and no measurable effect at all on their learning and memory.

Publishing their findings today in the academic journal Proceedings of the Royal Society B, the authors say the insect-specific compound has huge potential as an environmentally-benign, ‘bee-safe’ bio-pesticide and an alternative to the chemical neonicotinoid pesticides which have been linked to declines in pollinator populations.

The project is part of the Insect Pollinators Initiative, jointly funded by the Biotechnology and Biological Sciences Research Council, Defra, the Natural Environment Research Council (NERC), the Scottish Government and the Wellcome Trust.

Honeybees perform sophisticated behaviours while foraging that require them to learn and remember floral traits associated with food. Disruption to this important function has profound implications for honeybee colony survival, because bees that cannot learn will not be able to find food and return to their hives.

In other news…

Congratulations to Vikram Patel, Professor of International Mental Health and Wellcome Trust Senior Research Fellow in Clinical Science, who has been awarded this year’s Rhoda and Bernard Sarnat International Prize in Mental Health by the Institute of Medicine of the USA. Professor Patel is only the second non-American to win the prize after Sir Michael Rutter.

Congratulations also to Roi Cohen Kadosh, Wellcome Trust Research Career Development Fellow at the University of Oxford who has won this year’s Spearman Medal from the British Psychological Society, in recognition of outstanding published work in psychology.

Finally, the HFEA published its report on the third scientific review into the safety and efficacy of mitochondrial replacement techniques this week, recommending that they be considered ‘not unsafe’ for use on a ‘specific and defined group of patients’.Jeremy Farrar Director of the Wellcome Trust, welcomed the findings, “Given this evidence, we urge Parliament to pass enabling regulations swiftly, to ensure that there is no delay in patients being able to access these life-changing techniques.”

Image credits: Pain – Adrian Cousins, Wellcome Images , Embryo – Chris Nurse, Wellcome Images, Honeybee – Credit Annie Cavanagh, Wellcome Images