Public Deliverables

This page provides access to the public deliverables produced throughout the CANDY project. These documents present results, methodologies and insights, making the project’s progress and outcomes openly available to stakeholders and the wider community. Browse the list below to explore the publicly available deliverables.

WP1 “Animal studies: pathogenic processes and critical time windows”

CANDY_D1.1 Report on developmental trajectories in NRNX1 and SHANK3 genetic mouse models

Executive Summary: To determine the developmental trajectory of co-morbidity phenotype expression and the modulatory role of neuroinflammation on the developmental trajectory in animal models (tasks 1.1 and 1.2.) we performed assessments of sensory processing and behavioural phenotypes in the Shank3 and Nrxn1 genetic mouse models at various development stages: 6-8 weeks, 12-14 weeks, and >18 weeks. In addition, electrophysiological (EEG) assessments focusing on sensory processing have also been performed in the Nrxn1 genetic mouse model at four time points: 6-8 weeks, 10-12 weeks, 14-16 weeks, and 18-20 weeks of age. These studies have revealed an interesting developmental sensory profile that shows slightly different trajectories across models. Brain tissue and blood samples for assessment of neuroinflammatory factors was analysed in 6- and 12-week-old animals. Based on the developmental sensory trajectories and brain analyses we will be testing time-dependent drug efficacy (tasks 1.3 and 1.4) on these behavioural and electrophysiological phenotypes by targeting pathogenic processes.

CANDY_D1.2 Report on developmental trajectories in PTCHD1 genetic mouse model

Executive Summary: A key element of the research in CANDY is to focus on rare genetic variants that increase the risk of NDDs and converge on common signaling pathways. Moreover, the CANDY project is testing whether NDD and common mental and somatic multimorbidity is related to specific “sensitive time points” in development. We focused on the PTCHD1 mouse model – a model carrying a rare high-impact mutation that in the human population is associated with increased risk of ID and ASD. PTCHD1 was hypothesized to regulate lipid homeostasis. Notably, alterations in cholesterol have been linked to NDD phenotypes and neuroinflammation. Thus, we probed lipid content in young adolescent and adult mice. Moreover, we assessed hyperactivity and cognitive performance in PTCHD1 model.

CANDY_D1.3 Report on effects of neuro-inflammation during early development

CANDY_D1.4 Report on the critical developmental windows for treatment intervention

Executive Summary: To determine the development trajectory of co-morbidity phenotype expression on the developmental trajectory in animal models, RUG performed assessments of sensory processing and behavioral phenotypes in the Shank3 and Nrxn1 genetic mouse models at various development stages: 6-8 weeks, 12-14 weeks, and >18 weeks. In addition, electrophysiological (EEG) assessments focusing on sensory processing have also been performed in the Nrxn1 genetic mouse model at four time points: 6-8 weeks, 10-12 weeks, 14-16 weeks, and 18-20 weeks of age. These studies have revealed an interesting developmental sensory profile that shows slightly different trajectories across models. Based on the developmental sensory trajectories and brain analyses we have implemented an intervention study to target these sensory phenotypes via a synaptic protein at the 12 weeks’ time point as a function of the Shank3 genotype. The proof of concept intervention study revealed that somatosensory targeting of the cofilin synaptic protein pathway did not change the sensory phenotype in this genetic mouse model.

WP2 “Translational Test Battery Development”

CANDY_D2.6 Protocol on translational behavioural and brain excitation-inhibition measures for exploitation

Executive Summary: This document describes Deliverable 2.6, involving a protocol for 1. the translational test battery for mice, and 2. The measurement of excitation/inhibition balance in mice.

The test battery addresses the six bio-behavioural domains that play a central role in CANDY:
1) social communication/social processing, 2) reward processing, 3) emotional reactivity, 4) predictability, 5) sensory processing, and 6) attention. These six biobehavioural domains are affected in neurodevelopmental disorders and their comorbidities and are measured in WP2 both in mice and in children. We describe the protocols for the tests that measure each of these domains.
The central hypothesis of the CANDY project is that the comorbidity between neurodevelopmental disorders and epilepsy converges on changes in the excitation / inhibition balance. The measurement of the excitation/inhibition balance is done at two levels: ex vivo, using western blotting, and in vivo, using magnetic resonance spectroscopic (MRS) imaging. We describe the protocols for both procedures.

CANDY_D2.7 Report on prototype of tablet based translational test battery for pre-schoolers

Executive Summary: Currently, our ability to assess social, cognitive and emotional development in neurodivergent children is hampered by the lack of suitable, validated tests. For example, many preschoolers (and notably those with neurodevelopmental conditions and/ or developmental delay) find it difficult to understand verbal task instructions, and the majority of neuropsychological tests can be fairly long and “boring”, so that children are either unwilling or unable to complete the tests. Moreover, for some domains, such as reward or sensory processing, relevant preschool versions are altogether lacking.
The goal of Deliverable 2.7 is to optimise and validate a set of touch screen tests in preschoolers with neurodevelopmental conditions (autism, ADHD, ID and/or epilepsy), and to implement the battery in clinical studies carried out in WP4 (the Preschool Brain Imaging and Behaviour Project) and WP5
(Multiplex Family Study. The majority of these tasks were initially developed between 2018-2020, and form part of a larger research project funded by the Simons Foundation for Autism Research (SFARI) to develop touch screen tests covering six bio-behavioural domains (social, cognitive, reward, emotional, un/predictability and sensory processes) and that are suitable for children from 3 years to adulthood. As part of CANDY WP2, Task 2, we focused specifically on optimising and validating sub-tests of relevance for ADHD and developmental delay (inhibitory control, social and ‘non-social’ reward processing, sustained attention, temporal discounting). We added to this a ‘translational test’ of social novelty (aligned with WP2, Task 1). Task development has been an iterative process. Evaluation criteria involve acquisition rates, face validity, construct validity, split-half and test-retest
reliability (as well as sensitivity to change). If a task does not meet acceptable thresholds on one or more criteria, the task was revised and then administered to a new group of children. Version 0.8.6 of the above tests was implemented in the AIMS-TRIALS/ CANDY Preschool Brain
Imaging and Behaviour Study. We report preliminary analyses of these tests as well as parallel work aimed at developing robust clustering techniques to identify “cognitive subgroups” based on the combination of test performance across domains. In additional task development work (Version 0.87 to 0.89) we used Bayesian Adaptive Optimatisation (an artificial intelligence algorithm) to “optimise” test components (speed, complexity) depending on a child’s performance and to create a shorter version of some subtests to increase acquisition rates in preschoolers with ID (such as rare genetic syndromes)

WP3 “Immune/inflammation and microbiome biomarkers”

CANDY_D3.2 Report on the association between gut microbiome and NDDs

Executive Summary: CANDY focuses on the shared and distinct mechanisms that underpin Autism Spectrum Disorder (ASD), Attention-Deficit Hyperactivity Disorder (ADHD), Intellectual Disability (ID) and epilepsy. With on-going transfer of fecal samples from autism, ADHD, ID and epilepsy participants from various collection sites within the consortium, we took the opportunity to combine the analysis of microbiome data from CANDY participants and of adult ADHD samples to explore association between microbial alterations and neurodevelopmental conditions (NDCs), and between microbial alterations and quantitative ASD traits. To identify robust gut-microbiome alterations in people with NDCs, we harmonized bioinformatic pipelines and analyses of raw 16S rRNA sequencing data from CANDY participants (NASD = 191, NNo ASD = 156) and four adult ADHD case-control studies (NADHD=312, NNoADHD=305). We investigated diversity and differential abundance of selected genera (logistic regression), corrected for age and sex, and meta-analysed the study results. 3 bacterial genera were robustly associated with neurodevelopmental conditions, and one genus overlapped with ASD. Existing literature points towards a role of these genera in inflammatory processes. Irreproducible results in the field of gut-microbiota research, due to between study heterogeneity and small sample sizes, stress the need for meta-analytic approaches and large sample sizes. While we robustly identified genera associated with neurodevelopmental conditions, functional studies are needed to shed light on mechanistic pathways. These results contribute significantly to the understanding of whether the microbiome structure differs between patients with NDCs (specifically ADHD and ASD) and healthy controls, and how specific NDC microbiome affects (the risk of) developing NDCs altogether with the quantitative symptoms.

WP4 “Clinical research platform for neurodevelopmental disorders”

CANDY_D4.3 Report on status of posting results CANDY-PIP

Executive Summary: The Preschool Brain Imaging and Behaviour (PIP) study is the first longitudinal, cross-condition preschool investigation to adopt a transdiagnostic framework. Its aim is to uncover the underlying mechanisms that drive differences in the development of clinical features (and functional outcomes) among neurodivergent and neurotypical preschool children, and to harness this knowledge to improve individual predictions and tailor support needs more effectively.
The study is exploratory in scope, acknowledging that prognostic markers may emerge as either diagnosis-specific or transdiagnostic in nature. To establish the added value of this novel approach over traditional methods, we first undertook conventional between-group comparisons for each measure (Goodwin et al., in prep). This deliverable 4.3 presents these results across various data domains including neurocognitive testing, eye-tracking, and brain structure (MRI, DTI), with EEG analyses currently underway.

WP5 “Human Genomics: Identification of common and rare genetic variants”

CANDY_D5.5 Report on status of posting results MPX

Executive Summary: This deliverable D5.5 Report on status of posting results MPX present how the dataset has been collected, stored and will be shared with the scientific community. It also details the data collected. We present the OWEY datalake of the Institut Pasteur and how we used the FAIR principles to format and homogenize the dataset.