The association of SLC 6 A 4 5‐ HTTLPR and TRPV 1 945 G > C with functional dyspepsia in K orea

Background and Aim The association of various genetic polymorphisms with functional dyspepsia ( FD ) has been suggested, but the results were still controversial. The aim of the present study was to assess the association of GNB 3 825 C > T , SLC 6 A 4 5‐ HTTLPR , ADRA 2 A ‐ 1291 C > G , CCK ‐1 R intron 779 T > C , and TRPV 1 945 G > C polymorphisms with FD based on R ome III criteria in K orea. Methods Study subjects were prospectively recruited from visitors to S eoul N ational U niversity B undang H ospital between 2009 and 2012. One hundred and twelve FD patients and 269 controls were enrolled. Results In SLC 6 A 4 5‐ HTTLPR polymorphism, the frequency of S / S genotype was significantly lower than that of L / L  +  L / S genotype in FD compared to controls ( P  < 0.05). After stratification according to Helicobacter pylori infection, the S / S genotype was significantly associated with H . pylori ‐positive epigastric pain syndrome ( EPS ) patients (adjusted odds ratio ( OR ) 0.46; 95% confidence interval ( CI ) 0.22–0.99; P  = 0.048). In TRPV 1 945 G > C polymorphism, the frequency of C / C genotype was lower in FD compared to controls ( P  = 0.057). The C carrier and C / C genotype was significantly associated with postprandial distress syndrome ( PDS ) and EPS , respectively (adjusted OR 0.47 and 0.43; 95% CI 0.25–0.90 and 0.20–0.93; P  = 0.021 and 0.033). After stratification, the significant associations remained in H . pylori ‐positive PDS and EPS patients (adjusted OR 0.37 and 0.28; 95% CI 0.16–0.88 and 0.09–0.85; P  = 0.024 and 0.025). Conclusions The genetic polymorphism of SLC 6 A 4 5‐ HTTLPR and TRPV 1 945G> C could be one of the pathophysiological factors of FD , especially in the case of H . pylori ‐positive patients in K orea.