PURPOSE: The five segmental duplications (LCR22-D to -H) at the distal region of chromosome 22 band q11.2 in the region immediately distal to the DiGeorge/velocardiofacial syndrome deleted region have been implicated in the recurrent distal 22q11.2 microdeletions. To date, the distal 22q11.2 microdeletions have been grouped together as a single clinical entity despite the fact that these deletions are variable in size and position depending on the mediating LCR22s. METHODS: Here, we report 13 new unrelated patients with variable size deletions in the distal 22q11.2 region as shown by cytogenomic array analyses. We compare our patients' clinical features with those of previously reported cases to better dissect the phenotypic correlations based on the deletion size and position. RESULTS: Six patients had the 1.1-Mb deletion flanked by LCR22-D and -E, and presented clinically with a phenotype consistent with previously reported cases with distal 22q11.2 microdeletions. Three patients had the 1.8-Mb deletion flanked by LCR22-D and -F, and presented with a similar phenotype. Four patients had the 700-kb deletion flanked by LCR22-E and -F, and presented with a milder phenotype that lacked growth restriction and cardiovascular defects. CONCLUSION: We suggest that the recurrent distal 22q11.2 microdeletions do not represent a single clinical entity, and propose categorizing these deletions into three types according to their genomic position. All three deletion types are thought to be pathogenic and are most often de novo. They all share some presenting features but also have their unique features and risks.
PURPOSE: The five segmental duplications (LCR22-D to -H) at the distal region of chromosome 22 band q11.2 in the region immediately distal to the DiGeorge/velocardiofacial syndrome deleted region have been implicated in the recurrent distal 22q11.2 microdeletions. To date, the distal 22q11.2 microdeletions have been grouped together as a single clinical entity despite the fact that these deletions are variable in size and position depending on the mediating LCR22s. METHODS: Here, we report 13 new unrelated patients with variable size deletions in the distal 22q11.2 region as shown by cytogenomic array analyses. We compare our patients' clinical features with those of previously reported cases to better dissect the phenotypic correlations based on the deletion size and position. RESULTS: Six patients had the 1.1-Mb deletion flanked by LCR22-D and -E, and presented clinically with a phenotype consistent with previously reported cases with distal 22q11.2 microdeletions. Three patients had the 1.8-Mb deletion flanked by LCR22-D and -F, and presented with a similar phenotype. Four patients had the 700-kb deletion flanked by LCR22-E and -F, and presented with a milder phenotype that lacked growth restriction and cardiovascular defects. CONCLUSION: We suggest that the recurrent distal 22q11.2 microdeletions do not represent a single clinical entity, and propose categorizing these deletions into three types according to their genomic position. All three deletion types are thought to be pathogenic and are most often de novo. They all share some presenting features but also have their unique features and risks.
Authors: Ana I Sánchez; Mary A García-Acero; Angela Paredes; Rossi Quero; Rita I Ortega; Jorge A Rojas; Daniel Herrera; Miguel Parra; Karol Prieto; Juana Ángel; Luz-Stella Rodríguez; Juan C Prieto; Manuel Franco Journal: Mol Syndromol Date: 2020-02-05
Authors: Tommy Hu; Paul Kruszka; Ariel F Martinez; Jeffrey E Ming; Emily K Shabason; Manu S Raam; Tamim H Shaikh; Daniel E Pineda-Alvarez; Maximilian Muenke Journal: Am J Med Genet C Semin Med Genet Date: 2018-06 Impact factor: 3.908
Authors: Carla S D'Angelo; Monica C Varela; Cláudia Ie de Castro; Chong A Kim; Débora R Bertola; Charles M Lourenço; Ana Beatriz A Perez; Celia P Koiffmann Journal: Mol Cytogenet Date: 2014-10-31 Impact factor: 2.009
Authors: E Inzaghi; A Deodati; S Loddo; M Mucciolo; F Verdecchia; E Sallicandro; G Catino; M Cappa; A Novelli; S Cianfarani Journal: J Endocrinol Invest Date: 2021-07-13 Impact factor: 4.256
Authors: Valerie Lindgren; Anne McRae; Richard Dineen; Alexandria Saulsberry; George Hoganson; Michael Schrift Journal: Mol Genet Genomic Med Date: 2015-04-16 Impact factor: 2.183