ACVR1C, TGFBR2, TGFBR3, ACVR2A, ACVR1, BMPR1A and BMPR2 were lower in breast tumours while ACVR1B and BMPR1B exhibited relatively higher expression levels in paired tumours compared with normal breast tissues, in the TCGA_BRCA cohort. The gene discussed is ACVR1B; the disease is neoplasm.