[Systemic sclerosis. Part 2. Epigenetic factors in the pathogenesis of clinical manifestations].

Systemic sclerosis is a complex autoimmune disease characterized by immune activation, fibrosis of the skin and internal organs and vasculopathy affecting predominantly the microvessels with a predilection for women. The genetic background of systemic sclerosis is still full of unanswered questions, with classical genetics able to explain only some systemic sclerosis cases. Novel advances concerning epigenetics give us new insight into pathogenesis of systemic sclerosis. This review focuses on results of recent reports on epigenetic modifications of the gene functions and X inactivation changes in pathogenesis of systemic sclerosis. Current evidence demonstrates DNA heavy methylation (FLI1, NOS3, BMPRII) and hypomethylation of regulatory genes (CD40L, CD70), histone code modifications, abnormal expression of large spectrum of microRNAs.