Background: This study aims to determine the associations between single-nucleotide polymorphisms (SNPs) in G-protein-coupled receptor class C group 6 member A​​​​​​​ (GPRC6A) and serine protease inhibitor, Kazal type 1 (SPINK1) genes and the clinical characteristics, including clinical symptoms, pancreatic enzyme abnormalities, and exocrine pancreatic function, with refractory functional dyspepsia (R-FD). This evidence concerns the gene SPINK1 and Fabry disease.