Whole blood gene expression profiling distinguishes systemic sclerosis‐overlap syndromes from other subsets

Among autoimmune rheumatic diseases, systemic sclerosis (SSc) is especially challenging due to its clinical diversity, reflected by the extent of skin and internal organ involvement 1 . Besides the two major subsets, limited and diffuse SSc (lcSSc, dcSSc), a substantial number of SSc cases exhibit overlap features of another rheumatic disease, summarized as SSc-overlap syndromes. A few of these are already well characterized by their specific clinical course and circulating antibodies (e.g., mixed connective tissue disease, polymyositis-scleroderma syndrome).