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14 Headlines Depression, autism and DNA Darren Day and Bryony Thorne talk about their research into neuropsychiatric disorders Dr Darren Day and his PhD student Bryony Thorne have been investigating how our DNA, and even viruses, are linked to neuropsychiatric disorders. Dr Day, a molecular geneticist, says scientists still don’t know exactly what causes such disorders, but we do know that genes and environment likely play a part. In 2019 Dr Day received a small project grant from the Neurological Foundation to study how differences in specific parts of our DNA can make us more or less likely to suffer from depression or anxiety. In 2020 Bryony received the W&B Miller Scholarship from the Neurological Foundation to add to our understanding of the relationships between DNA, environment and changes in brain development. Bryony is particularly interested in genetic risk factor and gender differences for neuropsychiatric disorders. “This knowledge is essential in order to develop therapeutic interventions to reduce the potential of neuropsychiatric disorders,” Bryony says. Dr Darren Day describes the research he and Bryony are involved in to better understand the underlying mechanisms of developing ASD and where to target therapies. Serotonins and autism Children with Autism Spectrum Disorder (ASD) will face a number of challenges in life. It affects a person’s ability to communicate both verbally and non-verbally, their social skills and behaviour. As the name suggests it is a spectrum, so each individual with ASD will experience different challenges and these will vary over time. Neuro- psychiatric disorders such as ASD also have a significant economic and health cost to society. Scientists still don’t know exactly what causes ASD. We do know that genes and environment likely play a part. Our research group in the School of Biological Sciences seeks to understand the molecular basis of how genes and environment interact to increase the risk for developing ASD. This knowledge is essential in order to develop therapeutic interventions to reduce the potential of neuropsychiatric disorders. The incidence of ASD is increasing, partly through better identification. We also know that infection with an RNA virus such as influenza has been shown to significantly increase the risk of developing neuropsychiatric disorders. By inference this also includes people who have recovered from COVID-19, which is an RNA virus. Exposure to a virus while in the womb, or what we refer to as Maternal Immune Activation (MIA), is also an important risk factor. How and why this leads to an increased risk of autism is unclear. It is well-established that environmental and genetic influences on the hormone serotonin impacts neuropsychiatric disorders, but likewise, detailed understanding of the mechanisms of how and why this happens is lacking. We, and others, have proposed a model in which genetic factors that modulate serotonin signalling during development, in conjunction with environmental stress, leads to subtle alterations in brain development, that in turn lead to changes in vulnerability to developing neuropsychiatric disorders. One potential explanation for this is epigenetics. Epigenetics is when environmental influences alter the way the genetic code of DNA is read, unlike genetics which studies the inherited genes passed down from our parents. In epigenetics a gene’s structure may be altered or turned on or off, without changing the underlying gene sequence. Yet, these structural modifications are often heritable for one or two generations. Epigenetic changes to the genes that regulate serotonin and development is a likely mechanism by which environmental stressors, such as MIA, Research to better understand neuropsychiatric disorders is vital for the tens of thousands of New Zealanders living with Autism Spectrum Disorder (ASD) and Major Depressive Disorder (MDD). A research group in the School of Biological Sciences at Victoria University is edging closer to unlocking the secrets of what causes these diseases.