Neurodevelopmental risks in young children with an extra X or Y chromosome: the TRIXY study 2016

This longitudinal study (2016 - 2022) is focused on neurodevelopmental problems in young children with XXY, XXX and XYY, aged 1 to 6 years. The primary aim is understanding risk for psychopathology by focusing on social adaptation and underlying mechanisms in terms of self-regulation, with a strong neuroscience approach involving biomarkers (eyetracking and heart rate/skin conductance) and neurocognition. Research and clinical care are integrated within the new TRIXY (TRIsomy of the X and Y chromosomes) Expert Center.

A key objective is to link biomarkers and neurocognition to daily life functioning of children with SCT. Neurocognition and biomarkers (heart rate, skin conductance) will be used to predict individual differences in daily life functioning and risk for psychopathology, as measured with parent/teacher reports, clinical interviews and behavior observations. In order to help explain variability in outcome in this genetic condition, the role of environmental parameters will also be studied.

The key objectives are framed in 3 sub-projects:

1. To identify ‘neurocognitive’ risk markers in development that predict psychopathology in children with SCT. In the search for such risk markers, this sub-project will focus on social cognition, executive functioning and language. These neurocognitive functions will be linked to social, emotional and behavioral problems, including autism symptoms and ADHD symptoms. In assessing differential outcome, environmental parameters such as familial history of neurodevelopmental problems, socio-economic status, and stressful life events will also be taken into account.

2. To identify ‘neurobiological’ risk markers in development that predict social, emotional and behavioral problems in children with SCT. In the search for such biomarkers, this sub-project will focus on the regulation of social attention (eyetracking) and the regulation of emotional arousal (heart rate and skin conductance measures). The hypothesis is that deficiencies in this regulatory system are predictive of social, emotional and behavioral problems, and risk for psychopathology.

3. To evaluate effectiveness of cognitive-behavioral, parent mediated intervention tools targeted at stimulating development, minimizing ‘growing-into-deficit’ and thereby potentially reducing risk for social, emotional or behavioral problems. The focus is on preventive intervention, with high accessibility for parents (i.e. widely available at low costs).

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