BCL2A1 and rheumatoid arthritis: To screen the key MDEGs of RA, two algorithms were employed to screen potential diagnostic biomarkers, resulting in the identification of five overlapping genes related to diagnosis based on 88 MDEGs, utilizing LASSO logistic regression and SVM algorithms (BCL2A1, MTHFD2, LYRM2, FASTKD3, and ACACA) (Fig. 7A–C).