Objective To investigate the causal relationship between resistin and multiple myeloma (MM). Methods A two-sample Mendelian randomization analysis was conducted using genetic variants (SNPs) associated with resistin as instrumental variables and MM genome-wide association study (GWAS) data as the outcome event. Five analysis methods, including inverse-variance weighted (IVW), MR-Egger, weighted median, weighted model, and simple model were used to assess the causal impact of resistin on the risk of MM. Results None of the five analysis methods showed a causal relationship between resistin and multiple myeloma (P>0.05). Sensitivity analysis indicated consistent and robust results, with no evidence of horizontal pleiotropy, heterogeneity, outliers, or individual SNPs influencing the findings. Conclusion This Mendelian randomization study provides no support for a causal relationship between resistin and the risk of multiple myeloma.
Objective To evaluate the potential causal relationship between asthma and the risk of gastroesophageal reflux disease (GERD) using a two-sample Mendelian randomization study. Methods A large sample of genome-wide association study was used to summarize the data, and the genetic loci [single nucleotide polymorphisms (SNPs)] closely related to asthma were selected as instrumental variables, and Mendelian randomization analysis was conducted by inverse variance weighting, weighted median and MR-Egger method, respectively. At the same time, the multi-effect of MR-Egger was detected and the sensitivity analysis was carried out by Leave-one-out method to ensure the robustness of the results. Results A total of 77 SNPs closely related to asthma were selected as instrumental variables. The results of inverse variance weighted analysis showed a significant positive correlation between asthma and the occurrence of gastroesophageal reflux disease [odds ratio (OR)=1.044, 95% confidence interval (CI) (1.006, 1.083), P=0.024]. Weighted median results showed similar causality [OR=1.075, 95%CI (1.021, 1.133), P=0.006]. The MR-Egger regression results showed that there was a positive correlation between asthma and GERD, but there was no statistical significance [OR=1.080, 95%CI (0.983, 1.187), P=0.115]. The heterogeneity test results showed that there was no heterogeneity in the causal relationship between asthma and GERD (P>0.05). The results of the horizontal pleiotropy test showed that there was no horizontal pleiotropy in SNPs (P>0.05). The results of the retention test showed that no SNPs with significant impact on the results were detected. Conclusion There is a positive causal relationship between asthma and GERD.