MXRA8 and rheumatoid arthritis: Among these, negative causal associations with RA were observed for 10 proteins (AIF1, ARG2, ATP5IF1, CCL19, CDSN, MXRA8, RPA2, SLC16A1, TNF, and TNFRSF14), while positive causal associations were observed for two proteins (CEP43 and PADI2).