Association of genetic variants in GNβ3 with functional dyspepsia: a meta-analysis

Abstract

Background: Functional dyspepsia (FD) is a functional upper gastrointestinal disorder. The etiology and pathogenesis of FD remain unclear, with genetic factors playing an important role. Previous studies investigated the association of C825T in GNβ3 with FD, with conflicting results reported.

Aims: The aim of this meta-analysis is to assess the association of genetic variants in GNβ3 with FD.

Methods: We performed a systematic literature search in PubMed, Cochrane Library, Google Scholar, and Web of Knowledge, and conducted a meta-analysis to assess the association of C825T in GNβ3 with FD. For sensitivity analysis, we analyzed the association between C825T and subtypes of FD. We also performed meta-analyses separately for individual ethnic groups/countries of origin.

Results: A total of eight studies met the eligibility criteria and were included in our analyses. Our meta-analysis finds no association between 825CC and FD (OR 1.19, 95% CI 0.84-1.67, p = 0.328). However, the association is significant under an additive model (OR 0.59, 95% CI 0.38-0.92, p = 0.018). Sensitivity analysis indicated a significant association of C825T with FD in participants from Korea but not in those from Japan, Europe, or the United States. We also detected a significant association of this SNP with dysmotility.

Conclusions: The genetic variant C825T in GNβ3 is significantly associated with FD under an additive model and the association is race-specific. Further studies with larger samples sizes are needed to validate our findings and to explore the potential mechanism underlying the association.

Figure 1

Flow diagram of the selection process of the studies included in the meta-analyses Note: Please see the Methods Section for additional details.

Figure 2

Funnel plot for meta-analysis of C825T in GNB3. The x-axis is the standard error of the log-transformed odds ratio (log[OR]), and the y-axis is log[OR]. The horizontal line in the figure represents the overall estimated log-transformed odds ratio. The two diagonal lines represent the pseudo 95% confidence limits of the effect estimate.

Figure 3

Forest plot for meta-analysis of C825T in GNB3. Each study is represented by a square and a line. The mid-point of the square is the point estimate of that study, and the area of the square is proportional to the weight of the study. The width of the line represents the 95% confidence interval (CI) of the estimate of the study. The overall effect from meta-analysis is represented by a diamond whose width represents the 95% CI for the estimated odds ratio. The vertical dashed line is the line of no effect.