Additionally, Eijsbouts et al. [36] explained the familial nature of IBS by discovering six genetic loci for IBS susceptibility (BAG6, CKAP2/TPTE2P3, DOCK9, NCAM1, CADM2, and PHF2/FAM120A) and found that the first four genes are also linked to mood and anxiety disorders, which makes GAD and IBS closely related. This evidence concerns the gene PHF2 and irritable bowel syndrome.