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
- 4.1. 22Q11.2 Duplication / deletion
- 4.2. 2P16.3 (NRXN1)
- 4.3. 15Q11.2 (BP4)
- 4.4. 15Q13.3 (BP4.5-BP5)
- 4.5. 22Q11.21 (COMT)
- 4.6. 1Q21.1 distal
- 4.7. 16P11.2 proximal
- 4.8. 16P13.11
- 4.9. 16P13.2
- 4.10. 17Q12 (HNF1B) loss/gain
- 4.11. 16P12.1 (EEF2K, CDR2)
- 4.12. 15Q13.3 (BP 4-5)
- 4.13. 15Q11.2 (BP 1-2)
- 4.14. 2Q11.2 (A-B) loss/gain
- 4.15. 16P11.2 (BP 4-5) loss/gain
- 4.16. TAR (BP 2-3) loss
- 4.17. PWAS (BP 2-3) loss/gain
- 4.18. 16P11.2 (BP 4-5) loss/gain
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 an up to 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
1q21.1 (BP 3-4) loss/gain
Duplication.
HR: 2.656
4.7. 16P11.2 proximal
Duplication.2
4.8. 16P13.11
Duplication.2
16p13.11 (BP 2-3) HR: 2.016
16p13.11 (BP 2-3)
Deletion.
HR: 2.266
4.9. 16P13.2
Source:7
4.10. 17Q12 (HNF1B) loss/gain
Deletion.
HR: 4.246
Duplication.
HR: 4.196
4.11. 16P12.1 (EEF2K, CDR2)
Deletion.
HR: 1.866
4.12. 15Q13.3 (BP 4-5)
Deletion.
HR: 2.516
4.13. 15Q11.2 (BP 1-2)
Deletion.
HR: 1.436
Duplication.
HR: 1.426
4.14. 2Q11.2 (A-B) loss/gain
Duplication.
HR: 2.616
4.15. 16P11.2 (BP 4-5) loss/gain
Duplication.
HR: 2.636
4.16. TAR (BP 2-3) loss
Duplication.
HR: 1.766
4.17. PWAS (BP 2-3) loss/gain
Duplication.
HR: 3.646
4.18. 16P11.2 (BP 4-5) loss/gain
Duplication.
HR: 2.636
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