Author Interviews, Genetic Research / 30.09.2020 Interview with: Professor Sarah Medland Coordinator of the Mental Health Research Program and Group Leader Psychiatric Genetics QIMR Berghofer Medical Research Institute What is the background for this study? Response: This large collaborative project involving participants and researchers from around the world which has been underway for about 10 years. The aim was to try and identify genetic variants that influence handedness with the goal of increasing our knowledge about the way lateralization develops in behaviour and in the brain. In this project we were able to bring together results from cohort studies conducted by academic collaborators, the UK Biobank and 23andMe yielding a total sample size of over 1.7 million participants. Working with Professor David Evans the co-senior author of the paper (University of Queensland) and Dr Gabriel Cuellar-Partida the first author of the paper (formally UQ now at 23andMe) and the other researchers who worked on the project we meta-analysed the genome-wide association analysis results from the cohorts and were able to identify 41 genetic variants that influence left-handedness and 7 that influence ambidextrousness. (more…)
Author Interviews, Genetic Research / 09.09.2019 Interview with: Prof. Dominic Furniss, DM MA MBBCh FRCS Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science University of Oxford What is the background for this study? Response: We knew that there was a genetic component to handedness. Twin studies estimated that around 25% of the variation in handedness seen in the human population is down to genetic factors. Genetic factors associated with left handedness had been shown in specific patient populations, but this study has found factors in the general population and correlated them with functional brain imaging to shed more light on this fascinating subject. We have used both genetic and imaging data from the UK Biobank study to discover genetic variants that are related to left handedness. We have correlated these variants with changes in brain imaging, in particular showing increased functional connectivity between the language processing areas of the brain in left handers. The genetic variants that are associated with left handedness are also near to genes involved in forming the internal skeleton of neurons, and important in brain development, suggesting that being left handed is in part caused by a difference in brain development. It is clear, however, that there are also many non-genetic influences on whether a person is left handed or not. In addition, we confirmed previous observations that being left handed is associated with other neurological problems, such as schizophrenia, and protective of others, such as Parkinson's disease, and showed that this is related to shared genetic factors, and likely reflects differences in brain development.  (more…)
Author Interviews, Pediatrics / 10.01.2019 Interview with: PHILIPPE P. HUJOEL PhD, DDS, MSD, MS Professor, Oral Health Sciences Adjunct Professor, Epidemiology Adjunct Professor, Periodontics Dental Public Health Sciences, School of Dentistry University of Washington What is the background for this study? Response: In 2012, an economist, Kevin Denny, identified an association between breastfeeding and handedness.  The newly published study attempted to refute this association in a larger population, and with more control for potential confounding variables. (more…)