4. Copy number variations as gene candidates in ADHD
Copy number variants (CNVs) are genetic variations that include deletions and duplications of chromosome segments. CNVs occur in less than 1% of the total population. However, they have a major impact on the risk of1
4. Copy number variations (CNV), which appear to be involved in the development of ADHD
Gene databases:
omim.org and http://www.uniprot.org/
4.1. 22Q11.2 Duplication / deletion
The 22q11.2-deletion syndrome Occurs once in 2150 births, the prevalence of ADHD at 22q11.2Del is around 6% to 37%.5
The 22q11.2-duplication syndrome Occurs once in 1600 births, the ADHD prevalence at 22q11.2Dup is around 18.2 % to 44 %.5
More on this under Monogenetic causes of ADHD.
4.2. 2P16.3 (NRXN1)
Exonic NRXN1 deletions occur in 0.039 to 0.07% of all people and are associated with a 10 to 20% risk of ADHD and up to a 20-fold increased risk of other psychiatric disorders.
More on this under Monogenetic causes of ADHD.
4.3. 15Q11.2 (BP4)
Deletion.2
4.4. 15Q13.3 (BP4.5-BP5)
Deletion.2
4.5. 22Q11.21 (COMT)
Deletion.2
Duplication.2
4.6. 1Q21.1 distal
Duplication.2
4.7. 16P11.2 proximal
Duplication.2
4.8. 16P13.11
Duplication.2
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Gudmundsson, Walters, Ingason, Johansson, Zayats, Athanasiu, Sonderby, Gustafsson, Nawaz, Jonsson, Jonsson, Knappskog, Ingvarsdottir, Davidsdottir, Djurovic, Knudsen, Askeland, Haraldsdottir, Baldursson, Magnusson, Sigurdsson, Gudbjartsson, Stefansson, Andreassen, Haavik, Reichborn-Kjennerud, Stefansson (2019): Attention-deficit hyperactivity disorder shares copy number variant risk with schizophrenia and autism spectrum disorder. Transl Psychiatry. 2019 Oct 17;9(1):258. doi: 10.1038/s41398-019-0599-y. ↥ ↥ ↥ ↥ ↥ ↥ ↥ ↥
Ramos-Quiroga JA, Sánchez-Mora C, Casas M, Garcia-Martínez I, Bosch R, Nogueira M, Corrales M, Palomar G, Vidal R, Coll-Tané M, Bayés M, Cormand B, Ribasés M (2014): Genome-wide copy number variation analysis in adult attention-deficit and hyperactivity disorder. J Psychiatr Res. 2014 Feb;49:60-7. doi: 10.1016/j.jpsychires.2013.10.022. PMID: 24269040. ↥
Williams NM, Zaharieva I, Martin A, Langley K, Mantripragada K, Fossdal R, Stefansson H, Stefansson K, Magnusson P, Gudmundsson OO, Gustafsson O, Holmans P, Owen MJ, O’Donovan M, Thapar A (2010): Rare chromosomal deletions and duplications in attention-deficit hyperactivity disorder: a genome-wide analysis. Lancet. 2010 Oct 23;376(9750):1401-8. doi: 10.1016/S0140-6736(10)61109-9. PMID: 20888040; PMCID: PMC2965350. ↥
Sauter C, Romanos M, Radtke, F (2024): Deletions- und Duplikationssyndrom 22q11.2 und ADHS, neue AKZENTE Nr. 129 3/2024, 10 ↥ ↥