Cancer Genetics and Cytogenetics 126 (2001) 162–165 0165-4608/01/$ – see front matter © 2001 Elsevier Science Inc. All rights reserved. PII: S0165-4608(00)00402-7 Short communication No cytogenetic evidence for involvement of gene(s) at 2p16 in sporadic cardiac myxomas: cytogenetic changes in ten sporadic cardiac myxomas Trijnie Dijkhuizen a, *, Bauke de Jong a , Jacobus J. Meuzelaar c , Willemina M. Molenaar b , Eva van den Berg a a Department of Medical Genetics, the University of Groningen, Antonius Deusinglaan 4, 9713 AW Groningen, The Netherlands b Department of Pathology, the University of Groningen, Antonius Deusinglaan 4, 9713 AW Groningen, The Netherlands c Department of Cardiothoracic Surgery, University Hospital, Groningen, The Netherlands Received 3 August 2000; accepted 2 October 2000 Abstract Cardiac myxomas are significant causes of cardiovascular morbidity and mortality. Their genetic background is presently unknown. Recently, linkage analysis in cardiac myxomas of Carney com- plex patients has indicated that 2p16 and 17q2 might carry genes responsible for the development of hereditary cardiac myxomas. Less is known about sporadic cardiac myxomas. To date, cytoge- netic analysis has been performed on 13 sporadic cases, and no specific rearrangement has been deduced. We studied 15 sporadic cardiac myxomas and reviewed the literature. Ten of the present cases revealed abnormal karyotypes with clonal and nonclonal rearrangements including dicentric chromosomes and telomeric associations. No cytogenetic evidence was found for a role of 2p16 in the development of sporadic cases. Region 17q2 was involved in structural rearrangements, but to a lesser extent than other regions. Structural rearrangements involving regions 12p1 and 17p1 are more frequently present and might therefore harbor genes important for the development of spo- radic cardiac myxomas. © 2001 Elsevier Science Inc. All rights reserved. Cardiac myxoma is the most common tumor of the heart, occurring as a single sporadic lesion or as part of the inher- ited Carney complex syndrome. Cardiac myxomas can arise in any of the four chambers or, rarely, on the heart valves. About 90% are located in the atria, with a left to right ratio of approximately 4:1 [1]. Their histogenesis has been con- troversial, but currently they are believed to be neoplasms based on observations in tissue culture, chromosome analy- sis, and DNA-ploidy [2–8]. Although they are considered benign, these neoplasms can be fatal owing to valve ob- struction or can result in serious embolic events if not diag- nosed early and removed. Cardiac myxomas are usually found as single sporadic lesions but, 7–10% of patients have familial cardiac myxoma syndrome, known as Carney com- plex [1,9]. An autosomal dominant transmission, multiple cardiac and extracardiac myxomas, spotty pigmentation, and endocrine overactivity characterize this syndrome. Cy- togenetic analysis revealed abnormal karyotypes in three of five myxomas of Carney complex patients (Table 1 [3,5,6]). Based on linkage analysis, two loci have been proposed for genes causally related to the Carney complex: 2p16[10] and 17q2[11], but the responsible disease gene(s) have not been identified as yet. Cytogenetic data on sporadic cardiac myxoma are lim- ited. A total of 13 cases have been studied thus far. Cytoge- netic changes were observed in ten cases (Table 1) [2–4,12]. A tendency for the formation of dicentric chromosomes and telomeric associations (tas) was described as the most strik- ing feature, resembling the findings in cardiac myxomas of Carney complex patients. Tas formation is the end-to-end fu- sion of cytogenetically appearing intact chromosomes, probably caused by critical loss of telomeric DNA from one or more chromosomes. Tas formation marks a specific type of genetic instability that has been observed in other neo- plasms (i.e., giant cell tumors of bone, malignant fibrous * Corresponding author. Department of Medical Genetics, University of Groningen, Antonius Deusinglaan 4, 9713 AW Groningen, The Nether- lands. Tel. +31-503-3632925; fax: +31-50-3632947. E-mail address: t.dijkhuizen@medgen.azg.nl. (T. Dijkhuizen).