Chromosome 22q11.2 Deletion Syndrome

1. Elaine Pereira, MD* 2. Robert Marion, MD* 1. *Children’s Hospital at Montefiore, Bronx, NY. 1. 1. Jones KL, 2. Crandall Jones M, 3. del Campo M 22q11.2 Microdeletion Syndrome (Velo-Cardio-Facial Syndrome, DiGeorge Syndrome, Shprintzen Syndrome). In: Jones KL, Crandall Jones M, del Campo M, eds . Smith’s Recognizable Patterns of Human Malformation. 7th ed. Philadelphia, PA: Elsevier Saunders; 2013:358–361 2. 1. McDonald-McGinn DM, 2. Sullivan KE Chromosome 22q11.2 Deletion Syndrome (DiGeorge Syndrome/Velocardiofacial Syndrome). McDonald-McGinn DM, Sullivan KE. Medicine (Baltimore). 2011;90(1):1–18 [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] 3. 1. Bassett AS, 2. McDonald-McGinn DM, 3. Devriendt K, 4. et al Practical Guidelines for Managing Patients with 22q11.2 Deletion Syndrome. Bassett AS, McDonald-McGinn DM, Devriendt K, et al; International 22q11.2 Deletion Syndrome Consortium. J Pediatr. 2011;159(2):332-9.e.1 [OpenUrl][5][CrossRef][6][PubMed][7][Web of Science][8] 4. 1. Butcher NJ, 2. Chow EW, 3. Costain G, 4. Karas D, 5. Ho A, 6. Bassett AS Functional Outcomes of Adults With 22q11.2 Deletion Syndrome. Butcher NJ, Chow EW, Costain G, Karas D, Ho A, Bassett AS. Genet Med. 2012;14(10):836–843 [OpenUrl][9][CrossRef][10][PubMed][11] In recognition of their unifying molecular etiology, the conditions previously known as velocardiofacial syndrome, DiGeorge syndrome, Shprintzen syndrome, and conotruncal anomaly face syndrome have been grouped into what is now termed the “22q11.2 deletion syndrome” (22Q11.2DS). The disorder that results from this microdeletion and demonstrates an autosomal dominant inheritance pattern has a nearly equal distribution among males and females. Although its prevalence is quoted as between 1 in 3,000 and 1 in 6,000, the phenotype may be subtle, leading to underdiagnosis of the most mildly affected individuals. The 22Q11.2DS is a contiguous gene syndrome; the critical region includes up to 40 genes. Currently, the actual cause of the phenotypic features is unclear. TBX1 , one of the genes deleted in most affected individuals, is believed to play a major role during embryonic development of the heart, thymus, parathyroid gland, palate, and craniofacies. Much of the 22Q11.2DS phenotype results from abnormal differentiation of the third and fourth pharyngeal pouches, embryonic structures that form the thymus and parathyroid gland. Third and fourth pharyngeal pouch hypoplasia affects development of the first and second pharyngeal arches, which leads to maxillary and mandible formation. Disruption of embryogenesis in 22Q11.2DS can result in characteristic facial features, abnormalities of the palate and great vessels, congenital heart disease (CHD), hypoparathyroidism, and immune deficiencies. Facial features in individuals with 22Q11.2DS include a characteristic nose with a bulbous tip. Ears are often asymmetric, with overfolded helices and other minor anomalies. The eyes show … [1]: {openurl}?query=rft.jtitle%253DMedicine%26rft.stitle%253DMedicine%2B%2528Baltimore%2529%26rft.aulast%253DMcDonald-McGinn%26rft.auinit1%253DD.%2BM.%26rft.volume%253D90%26rft.issue%253D1%26rft.spage%253D1%26rft.epage%253D18%26rft.atitle%253DChromosome%2B22q11.2%2Bdeletion%2Bsyndrome%2B%2528DiGeorge%2Bsyndrome%252Fvelocardiofacial%2Bsyndrome%2529.%26rft_id%253Dinfo%253Adoi%252F10.1097%252FMD.0b013e3182060469%26rft_id%253Dinfo%253Apmid%252F21200182%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1097/MD.0b013e3182060469&link_type=DOI [3]: /lookup/external-ref?access_num=21200182&link_type=MED&atom=%2Fpedsinreview%2F36%2F6%2F270.atom [4]: /lookup/external-ref?access_num=000285867400001&link_type=ISI [5]: {openurl}?query=rft.jtitle%253DThe%2BJournal%2Bof%2Bpediatrics%26rft.stitle%253DJ%2BPediatr%26rft.aulast%253DBassett%26rft.auinit1%253DA.%2BS.%26rft.volume%253D159%26rft.issue%253D2%26rft.spage%253D332%26rft.epage%253D9.e1%26rft.atitle%253DPractical%2Bguidelines%2Bfor%2Bmanaging%2Bpatients%2Bwith%2B22q11.2%2Bdeletion%2Bsyndrome.%26rft_id%253Dinfo%253Adoi%252F10.1016%252Fj.jpeds.2011.02.039%26rft_id%253Dinfo%253Apmid%252F21570089%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [6]: /lookup/external-ref?access_num=10.1016/j.jpeds.2011.02.039&link_type=DOI [7]: /lookup/external-ref?access_num=21570089&link_type=MED&atom=%2Fpedsinreview%2F36%2F6%2F270.atom [8]: /lookup/external-ref?access_num=000292878400031&link_type=ISI [9]: {openurl}?query=rft.jtitle%253DGenetics%2Bin%2Bmedicine%2B%253A%2B%2Bofficial%2Bjournal%2Bof%2Bthe%2BAmerican%2BCollege%2Bof%2BMedical%2BGenetics%26rft.stitle%253DGenet%2BMed%26rft.aulast%253DButcher%26rft.auinit1%253DN.%2BJ.%26rft.volume%253D14%26rft.issue%253D10%26rft.spage%253D836%26rft.epage%253D843%26rft.atitle%253DFunctional%2Boutcomes%2Bof%2Badults%2Bwith%2B22q11.2%2Bdeletion%2Bsyndrome.%26rft_id%253Dinfo%253Adoi%252F10.1038%252Fgim.2012.66%26rft_id%253Dinfo%253Apmid%252F22744446%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [10]: /lookup/external-ref?access_num=10.1038/gim.2012.66&link_type=DOI [11]: /lookup/external-ref?access_num=22744446&link_type=MED&atom=%2Fpedsinreview%2F36%2F6%2F270.atom