Genomics-Microbiome Based Assessment of Bidirectional Causality Between Gut Microbiota and Psoriasis

Abstract

Qian Gao,1,2 Jing-Hua Liu,1,2 Wen-Yi Ma,1,2 Zi-Lin Cheng,1,2 Ping-Sheng Hao,1 Na-Na Luo1 1Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, People’s Republic of China; 2Chengdu University of Traditional Chinese Medicine, Chengdu, People’s Republic of ChinaCorrespondence: Ping-Sheng Hao; Na-Na Luo, Email [email protected]; [email protected]: Traditional observational studies have found a possible risk association of the gut microbiota for psoriasis. Meanwhile, psoriasis may also affect the changes in the gut microbiota. However, the available evidence does not demonstrate a reciprocal relationship between the gut microbiota and psoriasis. This limits our understanding on the role of the gut microbiota in the mechanisms of psoriasis.Methods: To address this question we used Mendelian randomization, a novel epidemiological approach, and acquired the largest current gut microbiota GWAS data from the MiBioGen consortium as well as psoriasis GWAS data from the FinnGen consortium, and performed two-sample bidirectional MR analyses using a multiple MR analysis approach. Finally, the robustness of the results was assessed by sensitivity analysis.Results: Our results indicate that five bacterial genera are causally related to psoriasis and psoriasis is causally related to four bacterial genera.Conclusion: These results suggest a bidirectional causal influence of psoriasis on the gut microbiota. Our results somewhat challenge the causal inferences of previous observational studies. We found that the specific bacterial genera with a risk effect on psoriasis were different from those found to characterize psoriasis in previous observational studies, and that these psoriasis-characterizing genera were inversely associated with psoriasis.Keywords: Mendelian randomization, psoriasis, causal relationship, gut microbiota, bidirectional Mendelian randomization analysis

Keywords

• mendelian randomization
• psoriasis
• causal relationship
• gut microbiota
• bidirectional mendelian randomization analysis.