A study by Manfredi et al. using a shotgun proteomic approach to analyze serum from 28 IBD patients and 17 controls found altered levels of the proteins KAIN, PRCC, and GELS in CD patients versus healthy controls and altered levels of LPPRC, SURF4, and CHADL in UC patients versus healthy controls. This evidence concerns the gene SURF4 and irritable bowel syndrome.