Comprehensive genome-wide association study of different forms of hernia identifies more than 80 associated loci

Genetic and biologic risk factors associated with hernia formation: A review

BACKGROUND

This systematic review aims to identify genetic and biologic markers associated with abdominal hernia formation.

METHODS

Following PRIMSA-guidelines, we searched PubMed, MEDLINE, Embase, Scopus, and COCHRANE databases.

RESULTS

Of 5946 studies, 65 were selected, excluding parastomal hernias due to insufficient data. For inguinal hernias, five studies unveiled 92 susceptible loci across 66 genes, predominantly linked to immune responses. Eleven studies observed elevated MMP-2 levels, with seven highlighting greater MMP-2 in direct compared to indirect inguinal hernias. One incisional hernia study identified unique gene-expression profiles in 174 genes associated with inflammation and cell-adhesion. In hiatal hernias, several genetic risk loci were identified. For all hernia categories, type I/III collagen ratios diminished.

CONCLUSIONS

Biological markers in inguinal hernias appears consistent. Yet, the genetic predisposition in incisional hernias remains elusive. Further research to elucidate these genetic and biological intricacies can pave the way for more individualized patient care.

Genetic analyses identify evidence for a causal relationship between Ewing sarcoma and hernias

Knowledge of Ewing sarcoma (EWS) risk factors is exceedingly limited; however, multiple small, independent studies have suggested a possible connection between hernia and EWS. By leveraging hernia summary statistics from the UK Biobank and a recently published genome-wide association study of EWS (733 EWS cases and 1,346 controls), we conducted a genetic investigation of the relationship of 5 hernia types (diaphragmatic, inguinal, umbilical, femoral, and ventral) and EWS. We discovered a positive causal relationship between inguinal hernia and EWS (OR 1.27, 95% confidence interval [CI] 1.01-1.59, and p = 0.041) through Mendelian randomization analysis. Further analyses suggested shared pathways through three genes: HMGA2, LOX, and FBXW7. Diaphragmatic hernia showed a stronger causal relationship with EWS among all of the hernia types (OR 2.26, 95% CI 1.30-3.95, p = 0.004), but no statistically significant local correlation pattern was observed. No evidence of a causal or genetic relationship was observed between EWS and the other three hernia types, including umbilical hernia, despite a previous report indicating an OR as high as 3.3. The finding of our genetic analysis provided additional support to the hypothesis that EWS and hernias may share a common origin.

No Causal Association Between Inguinal Hernia and Aortic Aneurysm Using Mendelian Randomization Analysis

Aortic aneurysm (AA) is a serious disease that affects the aging population worldwide. Potential risk or associated factors, such as inguinal hernia, have been suggested by conventional studies. In the present study, summary statistics data for the associations of inguinal hernia were derived from a large genome-wide association study including 18,791 inguinal hernia cases and 93,955 controls in the UK Biobank. Corresponding data of AA were extracted from FinnGen, comprising 7603 cases and 317,899 controls in Finland. The causal association was assessed using Mendelian Randomization-Egger, weighted median, and inverse variance weighting methods, and compared with observational estimates previously published. Our analysis found no convincing causal effect between genetically predicted inguinal hernia and the risk of AA (odds ratio [OR] = 1.05, 95% confidence interval [CI] = 0.85-1.31, P = .65), abdominal aortic aneurysm (AAA, OR = 1.15, 95% CI = 0.92-1.46, P = .22), and thoracic aortic aneurysm (TAA, OR = 1.05, 95% CI = 0.85-1.30, P = .67). The results are in contrast to previous observational evidence suggesting a potentially common causal association between inguinal hernia and AA. Further research is needed to better understand the interplay between risk factors and their impact on aneurysm development.

Causal associations between liver traits and Colorectal cancer: a Mendelian randomization study

OBJECTIVE

This study aimed to investigate the causal associations between several liver traits (liver iron content, percent liver fat, alanine transaminase levels, and liver volume) and colorectal cancer (CRC) risk using a Mendelian randomization (MR) approach to improve our understanding of the disease and its management.

METHODS

Genetic variants were used as instrumental variables, extracted from genome-wide association studies (GWAS) datasets of liver traits and CRC. The Two-Sample MR package in R was used to conduct inverse variance weighted (IVW), MR Egger, Maximum likelihood, Weighted median, and Inverse variance weighted (multiplicative random effects) MR approaches to generate overall estimates of the effect. MR analysis was conducted with Benjamini-Hochberg method-corrected P values to account for multiple testing (P < 0.013). MR-PRESSO was used to identify and remove outlier genetic variants in Mendelian randomization (MR) analysis. The MR Steiger test was used to assess the validity of the assumption that exposure causes outcomes. Leave-one-out validation, pleiotropy, and heterogeneity testing were also conducted to ensure the reliability of the results. Multivariable MR was utilized for validation of our findings using the IVW method while also adjusting for potential confounding or pleiotropy bias.

RESULTS

The MR analysis suggested a causal effect between liver volume and a reduced risk of CRC (OR 0.60; 95% CI, 0.44-0.82; P = 0.0010) but did not provide evidence for causal effects of liver iron content, percent liver fat, or liver alanine transaminase levels. The MR-PRESSO method did not identify any outliers, and the MR Steiger test confirmed that the causal direction of the analysis results was correct in the Mendelian randomization analysis. MR results were consistent with heterogeneity and pleiotropy analyses, and leave-one-out analysis demonstrated the overall values obtained were consistent with estimates obtained when all available SNPs were included in the analysis. Multivariable MR was utilized for validation of our findings using the IVW method while also adjusting for potential confounding or pleiotropy bias.

CONCLUSION

The study provides tentative evidence for a causal role of liver volume in CRC, while genetically predicted levels of liver iron content, percent liver fat, and liver alanine transaminase levels were not associated with CRC risk. The findings may inform the development of targeted therapeutic interventions for colorectal liver metastasis (CRLM) patients, and the study highlights the importance of MR as a powerful epidemiological tool for investigating causal associations between exposures and outcomes.

Umbilical Outpouchings in two Danish herds raising pigs with minimal use of antibiotics – Results from a field trial evaluating the efficacy of autogenous vaccines and iodine application

In Denmark, a Pure Pork concept for raising pigs without antibiotics was initiated in 2015 by the Danish Crown slaughterhouse cooperative. Pure Pork herds are characterised by minimal use of antibiotics and pigs are mainly treated individually. An increased prevalence of pigs suffering from umbilical outpouchings (UO) is a considerable challenge for Pure Pork producers. Umbilical outpouchings in pigs are challenging due to reduced welfare and increased workload and cost for the farmer. Therefore, Pure Pork producers require means other than antibiotic treatment to prevent UO. The primary objective of this study was therefore to evaluate the effect of autogenous sow vaccines based on bacteria isolated from the inflamed umbilici of piglets and a 7% iodine treatment at birth on the risk of pigs developing UO during the first 12 weeks of life. In addition, umbilical clinical and necropsy findings were presented, including variation over time and an identification of risk factors. A total of 5852 live-born piglets were included at birth from two Pure Pork herds. In this study, UO was defined as the presence of a rounded outpouching and/or a small firm protrusion at the umbilical area. Among 5614 pigs examined at weeks 5 and 12 and/or at death a total of 534 (9.5%) pigs were recorded with UO. The incidence of outpouchings was 10.2% for Herd A and 8.8% for Herd B. In the present field trial, neither autogenous vaccination of sows nor a 7% iodine spray on the umbilical area of new-born piglets had a statistically significant effect on the incidence of UO, but there was a tendency for a lower risk of UO in pigs treated with iodine spray at birth in one herd (OR = 0.7, p = 0.07), which might be worth investigating further. The risk factors for UO identified in this study included sow parity in one herd with more UO pigs from second parity sows and older compared to gilts (OR = 2.0, p = 0.02), batch in the second herd, and sex in both herds with male pigs at lower risk of UO development compared to female pigs (OR = 0.8, p = 0.006). Furthermore, antibiotic treatment as an indicator of the presence of other diseases resulted in a higher risk of UO compared to untreated pigs (OR = 1.9, p<0.0001). The presence of UO in one pig varied over time; For UO pigs examined alive at both week 5 and 12, 136 pigs (2.4%) had an UO record at week 5 but not at week 12 and 179 pigs (3.2%) did not have an UO at week 5 but a UO record at week 12. For 115 pigs (2.0%) an UO was recorded both at week 5 and week 12.

The Causal Association of Irritable Bowel Syndrome with Multiple Disease Outcomes: A Phenome-Wide Mendelian Randomization Study

BACKGROUND

This study aimed to identify novel associations between irritable bowel syndrome (IBS) and a broad range of outcomes.

METHODS

In total, 346,352 white participants in the U.K. Biobank were randomly divided into two halves, in which a genome-wide association study (GWAS) of IBS and a polygenic risk score (PRS) analysis of IBS using GWAS summary statistics were conducted, respectively. A phenome-wide association study (PheWAS) based on the PRS of IBS was performed to identify disease outcomes associated with IBS. Then, the causalities of these associations were tested by both one-sample (individual-level data in U.K. Biobank) and two-sample (publicly available summary statistics) Mendelian randomization (MR). Sex-stratified PheWAS-MR analyses were performed in male and female, separately.

RESULTS

Our PheWAS identified five diseases associated with genetically predicted IBS. Conventional MR confirmed these causal associations between IBS and depression (OR: 1.07, 95%CI: 1.01-1.14, p = 0.02), diverticular diseases of the intestine (OR: 1.13, 95%CI: 1.08-1.19, p = 3.00 × 10^-6), gastro-esophageal reflux disease (OR: 1.09, 95%CI: 1.05-1.13, p = 3.72 × 10^-5), dyspepsia (OR: 1.21, 95%CI: 1.13-1.30, p = 9.28 × 10^-8), and diaphragmatic hernia (OR: 1.10, 95%CI: 1.05-1.15, p = 2.75 × 10^-5). The causality of these associations was observed in female only, but not men.

CONCLUSIONS

Increased risks of IBS is found to cause a series of disease outcomes. Our findings support further investigation on the clinical relevance of increased IBS risks with mental and digestive disorders.

ADAMTS6: Emerging roles in cardiovascular, musculoskeletal and cancer biology

ADAMTS family members control mammalian development and disease, primarily through their function as proteases, by regulation of extracellular matrix composition. Until recently, ADAMTS6 was known as one of the orphan proteinases of the nineteen-member family with a relatively unknown expression pattern and function. Emerging focus on this enzyme has started to uncover these unknowns and revealed a vast importance and requirement of ADAMTS6 in cardiovascular and musculoskeletal development. In addition, ADAMTS6 has been linked to numerous disease settings including several types of cancer. This review summarizes the necessity of ADAMTS6 during development, its role in disease and requirement for essential prospective studies to fully realize its biological implications and potential for therapeutic intervention.

Advancing our understanding of genetic risk factors and potential personalized strategies for pelvic organ prolapse

Pelvic organ prolapse is a common gynecological condition with limited understanding of its genetic background. In this work, we perform a genome-wide association meta-analysis comprising 28,086 cases and 546,291 controls from European ancestry. We identify 19 novel genome-wide significant loci, highlighting connective tissue, urogenital and cardiometabolic as likely affected systems. Here, we prioritize many genes of potential interest and assess shared genetic and phenotypic links. Additionally, we present the first polygenic risk score, which shows similar predictive ability (Harrell C-statistic (C-stat) 0.583, standard deviation (sd) = 0.007) as five established clinical risk factors combined (number of children, body mass index, ever smoked, constipation and asthma) (C-stat = 0.588, sd = 0.007) and demonstrates a substantial incremental value in combination with these (C-stat = 0.630, sd = 0.007). These findings improve our understanding of genetic factors underlying pelvic organ prolapse and provide a solid start evaluating polygenic risk scores as a potential tool to enhance individual risk prediction.

Although pelvic organ prolapse is a common gynecological condition, the genetic component of disease risk is not well known. Here the authors find common genetic variants associated with the disease and present a polygenic risk score to enhance individual risk prediction.