title: Spontaneous chromosome damage (micronuclei) in systemic sclerosis and Raynaud's phenomenon.
abstract: OBJECTIVE
  To evaluate the prevalence of spontaneous chromosome damage in cultured peripheral lymphocytes of patients with systemic sclerosis (SSc), idiopathic Raynaud's phenomenon (RP), and suspected secondary RP, by means of molecular cytogenetic analysis.
  
  
  METHODS
  We studied 43 patients with SSc, 13 with idiopathic RP, and 16 with suspected secondary RP and 25 healthy controls. As a marker of chromosome alteration we used the micronucleus (MN) assay. All subjects were also classified for antinuclear antibodies, anticentromere antibodies (ACA), or Scl70. To identify the mechanism of MN formation, we also performed MN fluorescence in situ hybridization (FISH) analysis using a pancentromeric DNA probe.
  
  
  RESULTS
  Patients with SSc and subjects with RP showed significantly higher MN frequencies than controls (25.9 +/- 1.7 and 19.1 +/- 2.15, respectively, vs 9.4 +/- 2.2; p < 0.001). Subjects with suspected secondary RP displayed MN frequency (23.5 +/- 2.7) comparable to that of SSc patients, while spontaneous MN level in idiopathic RP subjects (13.6 +/- 3.0) did not differ significantly from controls (9.4 +/- 2.2). ACA positive subjects showed the highest MN frequencies (32.8 +/- 1.7) compared to subjects with a different antibody pattern (18.3 +/- 1.6).
  
  
  CONCLUSIONS
  Our results show the presence of higher levels of micronuclei in circulating lymphocytes of patients with SSc and subjects with suspected secondary RP. They also suggest a possible role of ACA in determining cytogenetic anomalies. FISH analysis indicated that both aneuploidogenic and clastogenic events contributed to the formation of MN observed in SSc patients and subjects with suspected secondary RP.
authors.affiliation: Istituto di Reumatologia, University of Siena, Italy. g.porciello@katamail.com
authors.forename: Giovanni
authors.initials: G
authors.lastname: Porciello
authors.forename: Roberto
authors.initials: R
authors.lastname: Scarpato
authors.forename: Clodoveo
authors.initials: C
authors.lastname: Ferri
authors.forename: Franca
authors.initials: F
authors.lastname: Storino
authors.forename: Francesca
authors.initials: F
authors.lastname: Cagetti
authors.forename: Gabriella
authors.initials: G
authors.lastname: Morozzi
authors.forename: Francesca
authors.initials: F
authors.lastname: Bellisai
authors.forename: Lucia
authors.initials: L
authors.lastname: Migliore
authors.forename: Roberto
authors.initials: R
authors.lastname: Marcolongo
authors.forename: Mauro
authors.initials: M
authors.lastname: Galeazzi
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D048629:Micronuclei, Chromosome-Defective; D008875:Middle Aged; D011928:Raynaud Disease / Q000235:genetics* / Q000276:immunology; D012595:Scleroderma, Systemic / Q000235:genetics* / Q000276:immunology
chemical_list: D001323:Autoantibodies