Each form of intellectual disability under study is a rare disease in its own right, and it is therefore difficult to study the variability of its expression. It therefore appears necessary to study large series of patients with intellectual disabilities. The objective is to identify variants in phenotype-modifying genes in patients with intellectual disability.

Thanks to the contribution of NGS analyses (exome and genome analysis), the rate of etiological diagnosis in intellectual disability is currently approaching 42% in some meta-analyses. At Bordeaux University Hospital, since 2017, 700 patients have been sequenced for intellectual disability, with a diagnostic rate of 33%.

In genetics, epistasis refers to the interaction between two or more genes. As part of its previous work, BIONOMEEX has developed an algorithm called GWAS-2D (genome wide association study 2 dimension) which makes it possible to observe, from a large number of samples and for a given phenotype, the relationships existing between two loci on the genome.

The GWAS-2DI project involves the reanalysis of exome sequencing data from patients with intellectual disabilities at Bordeaux University Hospital, using a GWAS-2D algorithm developed by BIONOMEEX to search for phenotype-modifying genes.

Inclusion Criteria:

• Patients with Intellectual Disability or related but not affected by them
• Major or minor with autorisation of legal representative
• Exome sequencing in Bordeaux University Hospital between 2018 and 2024

Exclusion Criteria:

• Refusal to participate in research protocols
• Refusal to participate expressed following receipt of information letter.

Patients with intellectual disabilities or related but not affected by them