Title: Investigating the causal effect between atopic dermatitis and allergic contact dermatitis: Atwo-sample Mendelian randomization studyAuthors: Zhenquan Xuan1,2,3, Jiawen Chen1,2,3, Zhen Zhang1,2,3, Yifeng Guo1,2,3, Hui Zhang1,2,3*, Zhirong Yao1,2,3*1Dermatology Center, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.2Department of Dermatology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.3Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China.