In particular, miRNAs regulate cytokines that play a critical role in the development of BD.14–17 For instance, Chen et al. reported that the increased expression of miRNAs is associated with the upregulation of tumour necrosis factor-alpha (TNF-α) and the downregulation of the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) genes in BD patients.14 Additionally, Abdelaleem et al. found that miR-146a (rs57095329) is associated with BD, and certain alleles and genotypes are linked to neurological manifestations and ocular and oral ulcers, but not with vascular disease.16 The gene discussed is CTLA4; the disease is Oral ulcer.