VDR and urolithiasis: Numerous candidate genes associated with urolithiasis have been discovered such as genes responsible for the receptor (e.g. vitamin D receptor or calcium-sensing receptor), ion channel (e.g. Claudin 16 or Claudin 19), transporter (e.g. sodium phosphate co-transporter), calcium channel (e.g. transient receptor potential cation channel subfamily V member 5 and member 6), chloride/H+ antiporter (e.g. CLCN5), β-glucuronidase (e.g. KLOTHO) and bicarbonate exchanger (e.g. soluble adenylate cyclase) [7].