Mutations in SLCO2A1 have been previously reported as the cause of primary hypertrophic osteoarthropathy (PHO).49, 50 Three out of five male patients with chronic enteropathy associated with SLCO2A1 had all of the major clinical features of PHO as well, such as digital clubbing, periostosis, and pachydermia. This evidence concerns the gene SLCO2A1 and Thickened skin.