Clinical, cytogenetic, and molecular characterization of six patients with ring chromosomes 22, including one with concomitant 22q11.2 deletion. Issue 7 (3rd April 2014)

• Record Type: Journal Article
• Authors: Guilherme, Roberta Santos; Soares, Karina Cunha; Simioni, Milena; Vieira, Tarsis Paiva; Gil‐da‐Silva‐Lopes, Vera Lúcia; Kim, Chong Ae; Brunoni, Décio; Spinner, Nancy Bettina; Conlin, Laura Kathleen; Christofolini, Denise Maria; Kulikowski, Leslie Domenici; Steiner, Carlos Eduardo; Melaragno, Maria Isabel
• Is Part Of: American journal of medical genetics. Volume 164:Issue 7(2014.)
• Page Start: 1659
• Page End: 1665
• Publication Date: 2014-04-03
• Subjects: Medical genetics -- Periodicals; 616.14205
• DOI: 10.1002/ajmg.a.36512
• Languages: English
• ISSNs: 1552-4825

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="ajmga36512-sec-0001" sec-type="section"> <p>We report here on six patients with a ring chromosome 22 and the range of cytogenetic and phenotypic features presented by them. Genomic analysis was carried out using classical and molecular cytogenetics, MLPA (Multiplex Ligation‐dependent Probe Amplification) and genome‐wide SNP‐array analysis. The ring was found in all patients, but Patient 6 displayed constitutional mosaicism with a normal cell line. Five patients had deletions in the ring chromosome 22, and in four of them the breakpoints—unique for each patient—could be identified by genome‐wide SNP‐array analysis. One patient presented with a 22q11.2 deletion concomitant with the deletion caused by the ring formation. Common phenotypic features included autism, speech delay and seizures, as previously reported for individuals with r(22) and/or 22q13.3 deletions. Investigation of the genes within the deletions revealed multiple genes related to development of the central nervous system, psychomotor delay, severe language impairment, hypotonia, and autistic symptoms. There was no clear correlation between the severity of clinical features and the size of the deleted segment. This study underscores the variability in ring structure and clinical presentation of the r(22) and adds information to the limited literature on this rare disorder. © 2014 Wiley Periodicals, Inc.</p> </sec> </abstract>