This study aims to identify protein markers for CLD and its progression, and develop a protein-based risk prediction model.<h4>Materials and methods</h4>We used proteome-wide Mendelian randomization (MR), Bayesian colocalization and summary-data-based MR with proteomic data from deCODE Genetics to identify CLD-related proteins. The gene discussed is SLC26A3; the disease is congenital secretory chloride diarrhea 1.