Also, no differences were observed between lcSScNoPAH and PAH, but further stratification for the presence of HLA-B*35 revealed slightly increased levels in lcSSc-NoPAH B35+ vs lcSSc-NoPAH B35- and slightly decreased levels in lcSSc-PAH B35+ vs lcSSc-NoPAH B35- (Additional file 4: Figure S2). The gene discussed is PAH; the disease is pulmonary arterial hypertension.