{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T03:24:49Z","timestamp":1780629889209,"version":"3.54.1"},"reference-count":21,"publisher":"S. Karger AG","issue":"5","license":[{"start":{"date-parts":[[2022,1,1]],"date-time":"2022-01-01T00:00:00Z","timestamp":1640995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2022,1,1]],"date-time":"2022-01-01T00:00:00Z","timestamp":1640995200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cytogenet Genome Res"],"published-print":{"date-parts":[[2022]]},"abstract":"<jats:p>Pediatric B-cell acute lymphoblastic leukemia (B-ALL) is associated with various specific cytogenetic and molecular markers that significantly influence treatment and prognosis. Intrachromosomal amplification of chromosome 21 (iAMP21) defines a rare distinct cytogenetic subgroup of childhood B-ALL, which is characterized by amplification of region 21q22.12 comprising the RUNX1 gene. Constitutional structural chromosomal abnormalities involving chromosome 21 confer an increased risk for B-ALL with iAMP21. Here, we report the development of B-ALL with iAMP21 in a 9-year-old child with a constitutional ring chromosome 21, r(21)c, uncovered after B-ALL diagnosis. Cytogenetic and microarray analysis of the post-therapy sample revealed an abnormal chromosome 21 lacking a satellite and having a deletion of the terminal 22q22.3 region, consistent with a constitutional ring chromosome 21, r(21)(p11.2q22). On a retrospective analysis, this ring chromosome was observed in the normal cells in the pre-treatment diagnostic specimen. Constitutional ring chromosome 21 may remain undetected in patients with mild or no neurodevelopmental phenotype, posing an unknown lifelong risk of developing B-ALL with iAMP21. Individuals with constitutional structural chromosome 21 rearrangements such as ring 21 require a close surveillance and long-term follow-up studies to establish their risk of B-ALL relapse and possibility of developing other malignancies. Germline analysis is recommended to all pediatric patients with iAMP21-related B-ALL to rule out structural chromosome 21 rearrangements and to elucidate molecular mechanisms of iAMP21 formation. <\/jats:p>","DOI":"10.1159\/000527025","type":"journal-article","created":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T22:00:50Z","timestamp":1670623250000},"page":"231-236","source":"Crossref","is-referenced-by-count":2,"title":["B-Cell Acute Lymphoblastic Leukemia with iAMP21 in a Patient with Constitutional Ring Chromosome 21"],"prefix":"10.1159","volume":"162","author":[{"given":"Vandana","family":"Baloda","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nidhi","family":"Aggarwal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Flavia G.","family":"Rosado","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5605-2123","authenticated-orcid":false,"given":"Sarah","family":"Mackey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James","family":"Felker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Svetlana A.","family":"Yatsenko","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2022,12,9]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1016\/0165-4608(83)90065-1"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1016\/0165-4608(87)90003-3"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2014-08-569228"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejmg.2016.01.006"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2141.2010.08314.x"},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.1038\/leu.2013.317"},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2013.49.1308"},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.3324\/haematol.2020.247031"},{"key":"ref9","doi-asserted-by":"publisher","DOI":"10.1038\/nature13115"},{"key":"ref10","doi-asserted-by":"publisher","DOI":"10.1002\/pd.1970150310"},{"key":"ref11","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2006-08-040436"},{"key":"ref12","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2013.48.9377"},{"key":"ref13","doi-asserted-by":"publisher","DOI":"10.1159\/000456572"},{"key":"ref14","doi-asserted-by":"publisher","DOI":"10.18632\/oncotarget.4586"},{"key":"ref15","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2011-01-329961"},{"key":"ref16","doi-asserted-by":"publisher","DOI":"10.1002\/gcc.20412"},{"key":"ref17","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0602360103"},{"key":"ref18","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2019-123766"},{"key":"ref19","doi-asserted-by":"publisher","DOI":"10.1002\/ajmg.a.62864"},{"key":"ref20","doi-asserted-by":"publisher","DOI":"10.3322\/caac.21219"},{"key":"ref21","doi-asserted-by":"publisher","DOI":"10.3978\/j.issn.2224-4336.2015.03.04"}],"container-title":["Cytogenetic and Genome Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/cgr\/article-pdf\/162\/5\/231\/3921969\/000527025.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/cgr\/article-pdf\/162\/5\/231\/3921969\/000527025.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T15:22:26Z","timestamp":1745421746000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000527025"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022]]},"references-count":21,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2023,2,23]]},"published-print":{"date-parts":[[2023,2,24]]}},"URL":"https:\/\/doi.org\/10.1159\/000527025","archive":["Portico"],"relation":{"is-supplemented-by":[{"id-type":"doi","id":"10.6084\/m9.figshare.21701024","asserted-by":"subject"}]},"ISSN":["1424-8581","1424-859X"],"issn-type":[{"value":"1424-8581","type":"print"},{"value":"1424-859X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022]]}}}