Tuesday, 24th November, 2015

12.00 - 13.00

Seminar Room, OS6, Second Floor, Oakfield House

How and why does an extra sex chromosome affect neurodevelopment? 

Abstract 

In the 1960s several centres embarked on newborn screening studies to identify children with an extra X or Y chromosome, with the aim of identifying how this additional genetic material affected development. The general conclusion was that verbal skills tended to be depressed in girls with trisomy X and in boys with Klinefelter’s syndrome (XXY) or XYY syndrome. This is intriguing because most genetic conditions have a more general effect on neurodevelopment, rather than selectively impacting language. Cognitive profiles are quite variable both between and within the different groups, but overall the effect of an additional sex chromosome is far less severe than that of other trisomies. Research on this topic is difficult to do because many cases go unidentified, and neonatal screening is no longer deemed ethical. However, in the UK cases are identified in the course of prenatal screening, and some are also identified when chromosome studies are done as part of medical investigations. We conducted a study of such cases and confirmed a high rate of language impairment but also found an increased rate of diagnosed autism spectrum disorder, which had not been noticed in earlier research. Nevertheless, there was a wide range of outcomes and some children were doing well with no indication of any problems at school or home. Currently we are doing a more in-depth investigation of language and related skills of a UK sample.

One question is whether the extra sex chromosome has similar effects on language and social development, regardless of whether the child has XXX, XXY or XYY karyotype, or whether there are subtle differences in the cognitive profile. We are also interested in the wide variation from child to child, and hope that by studying relationships between genes and behavior we might be able to find out more about why some children make good progress while others have more serious social or language problems. 

Biography 

Dorothy Bishop is a Wellcome Trust Principal Research Fellow and Professor of Developmental Neuropsychology at the University of Oxford, where she heads a programme of research into children’s communication impairments. Her main interests are in the nature and causes of developmental language impairments, with a particular focus on psycholinguistics, neurobiology and genetics. She is a supernumerary fellow of St John’s College Oxford, as well as a Fellow of the British Academy, the Academy of Medical Sciences and the Royal Society. As well as publishing in conventional academic outlets, she writes a popular blog (Bishopblog) with personal reactions to scientific and academic matters, and she tweets as @deevybee.  

ALL WELCOME