For heterogeneity, Cochrane's Q test, I<sup>2</sup> statistic, subgroup analyses, sensitivity analyses, and Bayesian meta-analysis were conducted.<h4>Results</h4>A total of 33 eligible studies, comparing IFN levels among 2307 SLE patients and 1599 HCs were included. This evidence concerns the gene IFNA1 and systemic lupus erythematosus.