Tendinopathy is a complex, multifaceted tendon disease that is often associated with overuse and causes significant health care costs with its high prevalence. At present, the pathogenesis and effective treatment of tendinopathy cannot be fully elucidated. This study aims to deeply explore and analyze the key genes, functional pathways, and immune infiltration characteristics of the occurrence and development of tendinopathy.MethodsThe gene expression profiles of GSE106292, GSE26051 and GSE167226 were downloaded from GEO database. The WGCNA analysis was performed on GSE106292 data set by the R package in R software, and differential gene analysis was performed on GSE26051 and GSE167226 data sets by combining and screening. The gene enrichment analysis of GO and KEGG and immune cell infiltration analysis were performed. Lasso logistic regression, support vector machine (SVM-REF) and Gaussian mixture model (GMMS) algorithm were used to screen and identify early diagnostic genes.ResultsWe have obtained a total of 171 DEGs through WGCNA analysis and screening of different expressed genes. By GO and KEGG enrichment analysis, it was found that these malregulated genes were related to mTOR, HIF-1, MAPK, NF-κB and VEGF signaling pathways. Immunoinfiltration analysis showed that M1 macrophages, activated mast cells and activated NK cells had infiltration significance. MacroD1 may be an early diagnosis gene, and it was found based on Lasso, SVM-REF and GMMS algorithm.ConclusionsBased on comprehensive bioinformatics analysis, we identified the potential early diagnosis genes MACROD1, key regulatory pathways and immune infiltration characteristics of tendinopathy. These key genes and pathways may be used as biomarkers and molecular therapeutic targets for early tendon injury to guide drugs and basic research.