In a randomized controlled clinical trial (RCT), a mixture of lactobacillus species, Lactobacillus rhamnosus and Lactobacillus reuteri, or probiotic Lactobacillus casei, were used to treat RA patients, which led to a reduction in proinflammatory cytokines IL-1α, IL-6, IL-12 and TNF-α [88], as well as a decrease in swollen joints [89]. The gene discussed is TNF; the disease is rheumatoid arthritis.