22q11.2 Distal Deletion / Duplication
22q11.2 Distal Deletion / Duplication
The 22q11.2 distal deletion is seen less commonly than the “typical” 22q11.2 deletion. It typically involves a deleted area of chromosome 22 covering 2.5-3 Mb. The 22q11.2 distal deletion is located a bit further down the q arm than the typical 22q11.2 deletion. The size of the distal deletion is variable.
People with 22q11.2 distal deletion may present with prematurity, delays in growth, intellectual disability, delays in development and speech, skeletal and heart defects and differences in facial features. Problems with behaviour including issues with sleep, impulse control, attention deficit hyperactivity disorder and autism spectrum disorder, as well as neurological findings such as seizures and changes in muscle tone, are also reported. The majority of these deletions arise spontaneously.
There have also been reports of 22q11.2 distal microduplications (Egger, et al, 2023)
Families will benefit from being connected to any of the 22q11.2 resources available.
Pamphlet from Unique on 22q11.2 Distal Deletion Syndrome
OMIM 611867 entry on 22q11.2 distal deletion
Facebook Group for those with 22q Distal Deletion Syndrome (Not affiliated with C22C)
Join C22C’s main Facebook Group to connect with other families.
Search PUBMED for articles on 22q11 distal deletion
Select References
Ben-Shachar, S., Ou, Z., Shaw, C. A., Belmont, J. W., Patel, M. S., Hummel, M., Amato, S., Tartaglia, N., Berg, J., Sutton, V. R., Lalani, S. R., Chinault, A. C., Cheung, S. W., Lupski, J. R., & Patel, A. (2008). 22q11.2 distal deletion: a recurrent genomic disorder distinct from DiGeorge syndrome and velocardiofacial syndrome. American Journal of Human Genetics, 82(1), 214–221. https://doi.org/10.1016/j.ajhg.2007.09.014
Egger, J., Verhoeven, W., Verbeeck, W., Sinnema, M., Stegmann, A., Stuurop, K., & De Leeuw, N. (2023). A Novel Distal 22Q11.21 Microduplication in a 43-Year-Old Male Patient with Mild Intellectual Disability, Social Cognitive Dysfunctions, and Anxiety. Clinical Neuropsychiatry, 20(5), 424–428. https://doi.org/10.36131/cnfioritieditore20230504
Lindgren, V., McRae, A., Dineen, R., Saulsberry, A., Hoganson, G., & Schrift, M. (2015). Behavioral abnormalities are common and severe in patients with distal 22q11.2 microdeletions and microduplications. Molecular Genetics & Genomic Medicine, 3(4), 346–353. https://doi.org/10.1002/mgg3.146
Mikhail, F. M., Burnside, R. D., Rush, B., Ibrahim, J., Godshalk, R., Rutledge, S. L., Robin, N. H., Descartes, M. D., & Carroll, A. J. (2014). The recurrent distal 22q11.2 microdeletions are often de novo and do not represent a single clinical entity: a proposed categorization system. Genetics in Medicine : Official Journal of the American College of Medical Genetics, 16(1), 92–100. https://doi.org/10.1038/gim.2013.79
Salah, S., Jaber, H., Frumkin, A., & Harel, T. (2023). Homozygous 22q11.2 distal type II microdeletion is associated with syndromic neurodevelopmental delay. American Journal of Medical Genetics. Part A, 191(10), 2623–2630. https://doi.org/10.1002/ajmg.a.63326