Chromosome aberrations in Raynaud's phenomenon.

Area of Science:

• Cytogenetics
• Molecular Biology
• Immunology

Background:

• Raynaud's phenomenon (RP) can be idiopathic or a precursor to systemic sclerosis (SSc).
• Assessing chromosomal damage in lymphocytes may reveal underlying disease mechanisms.
• Autoantibodies like anti-centromere (ACA) and anti-Scl-70 are markers for connective tissue diseases.

Purpose of the Study:

• To investigate spontaneous chromosome damage in lymphocytes of patients with idiopathic and pre-scleroderma Raynaud's phenomenon.
• To compare chromosome alteration rates using the micronucleus assay across different RP groups and healthy controls.
• To explore the association between autoantibody status (ANA-, ACA+, Scl 70+) and chromosomal damage.

Main Methods:

• Molecular cytogenetic analysis using the micronucleus assay on cultured peripheral lymphocytes.
• Study included 30 patients with pre-scleroderma RP, 30 with idiopathic RP, and 30 healthy controls.
• Fluorescence in situ hybridization (FISH) was used to identify micronucleus formation mechanisms.

Main Results:

• Pre-scleroderma RP subjects showed significantly higher micronucleus frequencies (37.0) compared to idiopathic RP (11.1) and controls (10.7) (p < 0.0001).
• Idiopathic RP subjects had micronucleus frequencies comparable to healthy controls.
• ACA+ subjects exhibited the highest micronucleus frequencies (41.0) compared to Scl 70+ subjects (25.0).
• FISH analysis did not reveal a prevalence of aneuploidogenic or clastogenic events in micronucleus formation.

Conclusions:

• Circulating lymphocytes in pre-scleroderma Raynaud's phenomenon patients demonstrate a higher rate of spontaneous chromosomal damage.
• Chromosomal instability in RP may be linked to specific autoantibody profiles, particularly ACA+.
• The micronucleus assay serves as a sensitive marker for detecting chromosomal alterations in pre-scleroderma RP.