TSSK1B and stiff skin syndrome: The inflammatory-specific consensus cluster also contains the genes FBN1 and AIF1. Previous work implicates FBN1 in SSc pathogenesis, as a duplication of FBN1 causes fibrosis in the Tsk1 mouse [58] and a point mutation in FBN1 causes the fibrotic phenotype in the Stiff Skin Syndrome mouse [59].