4. Copy number variations as gene candidates in ADHD
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
The 22q11.2 deletion syndrome occurs once in 2150 births, making it the most common deletion syndrome.
22q11.2Del usually develops de novo, i.e. not as an inheritance of genetic traits from the parents.
The prevalence of ADHD in 22q11.2Del is around 6% to 37%.1
Among people with ADHD, 0.14% were found to have 22q11.2Del.
The 22q11.2 duplication syndrome occurs once in 1600 births.
22q11.2Dup is usually inherited from the parents.
The prevalence of ADHD at 22q11.2Dup is around 18.2% to 44%.1
Among persons with ADHD, a 22q11.2Dup was found in 0.25 to 0.33%.
Other typical symptoms are
- Facial abnormalities
- congenital heart defects
- Immunodeficiencies
- Cleft palate
- Short stature
- Obesity
- Developmental delay
ADHD symptoms are treated according to the usual regimens. A low starting dosage with slow up-dosing is also recommended here.
4.2. 2P16.3 (NRXN1)
Deletion.2
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
Sauter C, Romanos M, Radtke, F (2024): Deletions- und Duplikationssyndrom 22q11.2 und ADHS, neue AKZENTE Nr. 129 3/2024, 10 ↥ ↥
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. ↥ ↥ ↥ ↥ ↥ ↥ ↥ ↥