Does the A9285G Polymorphism in Collagen Type XII α1 Gene Associate with the Risk of Anterior Cruciate Ligament Ruptures?

The Impact of Genetic Polymorphisms on Anterior Cruciate Ligament Injuries in Athletes: A Meta-Analytical Approach

This meta-analysis aimed to investigate the association between genetic polymorphisms in Collagen type 1 alpha-1 (COL1A1), Collagen type 3 alpha-1 (COL3A1), Collagen type 5 alpha-1 (COL5A1), and Collagen type 12 alpha-1 (COL12A1) genes and anterior cruciate ligament (ACL) injuries in athletes. A systematic search was diligently conducted on the PubMed and Web of Science databases to identify relevant studies on 5-9 September 2023. Only case-control studies were included in the meta-analysis. A total of 19 studies were reviewed, involving the analysis of 3522 cases and 6399 control subjects. Data relevant to the study objectives were extracted from these chosen studies and subsequently analyzed using either a random-effects or fixed-effects model. It indicates that individuals carrying the G allele in the COL1A1 (rs1107946) gene have a decreased risk of anterior cruciate ligament injuries (OR: -0.27, 95% CI: -0.42 to -0.12, p < 0.001). A similar relationship was observed in the dominant model, but this relationship was reversed in the recessive model (OR: 0.69, 95% CI: 0.33 to 1.05, p < 0.001). However, no significant associations were found in the COL3A1 (rs1800255) and COL5A1 (rs12722) genes. In the COL12A1 (rs970547) gene, the A allele was associated with an increased risk of anterior cruciate ligament injuries (OR: 0.18, 95% CI: 0.01 to 0.36, p = 0.041). This meta-analysis suggests that genetic variants in COL1A1 (rs1107946) and COL12A1 (rs970547) may be associated with ACL injuries in athletes. However, COL3A1 rs1800255 and COL5A1 rs12722 gene variants do not appear to have a significant association with these injuries.

Association of COL12A1 rs970547 Polymorphism with Elite Athlete Status

The role of genetics, as an intrinsic factor, in research of sports performance increases with every passing year. The polymorphism rs970547 of the COL12A1 gene is one of the most promising genetic markers linked to soft-tissue injuries. This study aimed to investigate whether COL12A1 rs970547 genotypes are associated with elite Lithuanian athletes from high-risk various sports, such as running, throwing, jumping, and football. The study involved 293 Lithuanian elite athletes and 287 healthy untrained individuals from the Lithuanian population. The results of this study suggest that the rs970547 T allele and TT genotype were significantly over-represented in the total athlete group compared to controls (p < 0.05). There was a significantly lower C allele frequency in the sprint/power group (16.9%) as well as in footballers (19.4%) compared to controls (33.3%, p < 0.05). Positive selection analysis results showed that the derived allele experiences selection pressure within the general population of Lithuanians. Taken together, the findings of this study suggested that COL12A1 rs970547 (T allele and TT genotype) is associated with elite athlete status, especially with sprint/power athlete and footballer`s performance. However, larger-scale studies within different ethnic backgrounds are still warranted to confirm the findings of our study.

A whole genome sequencing approach to anterior cruciate ligament rupture-a twin study in two unrelated families

Predisposition to anterior cruciate ligament (ACL) rupture is multi-factorial, with variation in the genome considered a key intrinsic risk factor. Most implicated loci have been identified from candidate gene-based approach using case-control association settings. Here, we leverage a hypothesis-free whole genome sequencing in two two unrelated families (Family A and B) each with twins with a history of recurrent ACL ruptures acquired playing rugby as their primary sport, aimed to elucidate biologically relevant function-altering variants and genetic modifiers in ACL rupture. Family A monozygotic twin males (Twin 1 and Twin 2) both sustained two unilateral non-contact ACL ruptures of the right limb while playing club level touch rugby. Their male sibling sustained a bilateral non-contact ACL rupture while playing rugby union was also recruited. The father had sustained a unilateral non-contact ACL rupture on the right limb while playing professional amateur level football and mother who had participated in dancing for over 10 years at a social level, with no previous ligament or tendon injuries were both recruited. Family B monozygotic twin males (Twin 3 and Twin 4) were recruited with Twin 3 who had sustained a unilateral non-contact ACL rupture of the right limb and Twin 4 sustained three non-contact ACL ruptures (two in right limb and one in left limb), both while playing provincial level rugby union. Their female sibling participated in karate and swimming activities; and mother in hockey (4 years) horse riding (15 years) and swimming, had both reported no previous history of ligament or tendon injury. Variants with potential deleterious, loss-of-function and pathogenic effects were prioritised. Identity by descent, molecular dynamic simulation and functional partner analyses were conducted. We identified, in all nine affected individuals, including twin sets, non-synonymous SNPs in three genes: COL12A1 and CATSPER2, and KCNJ12 that are commonly enriched for deleterious, loss-of-function mutations, and their dysfunctions are known to be involved in the development of chronic pain, and represent key therapeutic targets. Notably, using Identity By Decent (IBD) analyses a long shared identical sequence interval which included the LINC01250 gene, around the telomeric region of chromosome 2p25.3, was common between affected twins in both families, and an affected brother'. Overall gene sets were enriched in pathways relevant to ACL pathophysiology, including complement/coagulation cascades (p = 3.0e-7), purine metabolism (p = 6.0e-7) and mismatch repair (p = 6.9e-5) pathways. Highlighted, is that this study fills an important gap in knowledge by using a WGS approach, focusing on potential deleterious variants in two unrelated families with a historical record of ACL rupture; and providing new insights into the pathophysiology of ACL, by identifying gene sets that contribute to variability in ACL risk.

Tendon and Ligament Genetics: How Do They Contribute to Disease and Injury? A Narrative Review

A significant proportion of patients requiring musculoskeletal management present with tendon and ligament pathology. Our understanding of the intrinsic and extrinsic mechanisms that lead to such disabilities is increasing. However, the complexity underpinning these interactive multifactorial elements is still not fully characterised. Evidence highlighting the genetic components, either reducing or increasing susceptibility to injury, is increasing. This review examines the present understanding of the role genetic variations contribute to tendon and ligament injury risk. It examines the different elements of tendon and ligament structure and considers our knowledge of genetic influence on form, function, ability to withstand load, and undertake repair or regeneration. The role of epigenetic factors in modifying gene expression in these structures is also explored. It considers the challenges to interpreting present knowledge, the requirements, and likely pathways for future research, and whether such information has reached the point of clinical utility.

Collagen XII Deficiency Increases the Risk of Anterior Cruciate Ligament Injury in Mice

Anterior cruciate ligament (ACL) rupture is a common knee injury for athletes. Although surgical reconstruction is recommended for the treatment of ACL ruptures, 100% functional recovery is unlikely. Therefore, the discovery of risk factors for ACL ruptures may prevent injury. Several studies have reported an association between polymorphisms of the collagen XII gene COL12A1 and ACL rupture. Collagen XII is highly expressed in tendons and ligaments and regulates tissue structure and mechanical property. Therefore, we hypothesized that collagen XII deficiency may cause ACL injury. To elucidate the influence of collagen XII deficiency on ACL, we analyzed a mouse model deficient for Col12a1. Four- to 19-week-old male Col12a1-/- and wild-type control mice were used for gait analysis; histological and immunofluorescent analysis of collagen XII, and real-time RT-PCR evaluation of Col12a1 mRNA expression. The Col12a1-/- mice showed an abnormal gait with an approximately 2.7-fold increase in step angle, suggesting altered step alignment. Col12a1-/- mice displayed 20-60% ACL discontinuities, but 0% discontinuity in the posterior cruciate ligament. No discontinuities in knee ligaments were found in wild-type mice. Collagen XII mRNA expression in the ACL tended to decrease with aging. Our study demonstrates for the first time that collagen XII deficiency increases the risk of ACL injury.

COL12A1 rs970547 Polymorphism Does Not Alter Susceptibility to Anterior Cruciate Ligament Rupture: A Meta-Analysis

Objective: Currently available evidence regarding the association between collagen type XII α1 (COL12A1) polymorphism and risk of anterior cruciate ligament rupture (ACLR) remains elusive. The aim of our present study was to assess the association between COL12A1 rs970547 polymorphism and ACLR risk.

Methods: Five online databases, namely, PubMed, EMBASE, ISI Web of Science, CENTRAL, and CNKI, were searched from their inception data up to December 2020 to identify relative observational studies. The methodological quality of each individual study was evaluated using the Newcastle-Ottawa Scale (NOS). The “model-free approach” was employed to estimate the magnitude of effect of COL12A1 rs970547 polymorphism on ACLR, and the association was expressed using odds ratio (OR) and its associated 95% confidence interval (95% CI). Subgroup analysis was performed by ethnicity and sex of included subjects.

Results: Eight studies involving 1,477 subjects with ACLR and 100,439 healthy controls were finally included in our study. The methodological quality of included studies was deemed moderate to high based on NOS scores. The “model-free” approach suggested no genotype differences between ACLR and healthy control for the rs970547 polymorphism, but we still used the allele model to present the combined data. Under the random-effect model, there was no significant difference in the frequency of effecting allele between ACLR and control (OR: 0.91, 95% CI 0.77, 1.08; p = 0.28). Stratified analysis by sex and ethnicity also showed no difference in allele frequency.

Conclusion: The findings of this current meta-analysis suggested that rs970547 was not associated with ACLR risk in male, female, and the overall population among Asians or Caucasians.

COL12A1 Single Nucleotide Polymorphisms rs240736 and rs970547 Are Not Associated with Temporomandibular Joint Disc Displacement without Reduction

Temporomandibular disorders (TMDs) may affect up to 25% of the population, with almost 70% of these TMD cases developing malpositioning of the disc over time in what is known as internal derangement (ID). Despite significant efforts, the molecular mechanism underlying disease progression is not yet very well known. In this study, the role of COL12A1 rs970547 and rs240736 polymorphisms as potential genetic factors regulating ID was investigated. The study included 124 Caucasian patients of both sexes after disc displacement without reduction (DDwoR) in either one or two temporomandibular joints (TMJs), either of which meet the criteria for this condition. All patients underwent clinical examination and 3D digital imaging. The COL12A1 rs970547 and rs240736 polymorphisms were evaluated. There were no statistically significant differences in the chi-square test between the study group and healthy controls. The examined COL12A1 rs240736 and rs970547 polymorphisms do not contribute to DDwoR in Polish Caucasians.

Tendon and Ligament Injuries in Elite Rugby: The Potential Genetic Influence

This article reviews tendon and ligament injury incidence and severity within elite rugby union and rugby league. Furthermore, it discusses the biological makeup of tendons and ligaments and how genetic variation may influence this and predisposition to injury. Elite rugby has one of the highest reported injury incidences of any professional sport. This is likely due to a combination of well-established injury surveillance systems and the characteristics of the game, whereby high-impact body contact frequently occurs, in addition to the high intensity, multispeed and multidirectional nature of play. Some of the most severe of all these injuries are tendon and ligament/joint (non-bone), and therefore, potentially the most debilitating to a player and playing squad across a season or World Cup competition. The aetiology of these injuries is highly multi-factorial, with a growing body of evidence suggesting that some of the inter-individual variability in injury susceptibility may be due to genetic variation. However, little effort has been devoted to the study of genetic injury traits within rugby athletes. Due to a growing understanding of the molecular characteristics underpinning the aetiology of injury, investigating genetic variation within elite rugby is a viable and worthy proposition. Therefore, we propose several single nucleotide polymorphisms within candidate genes of interest; COL1A1, COL3A1, COL5A1, MIR608, MMP3, TIMP2, VEGFA, NID1 and COLGALT1 warrant further study within elite rugby and other invasion sports.

Anterior cruciate ligament injury risk factors in football

INTRODUCTION

Anterior cruciate ligament (ACL) lesion represents one of the most dramatic injuries in a football (soccer) player's career. There are many injury risk factors related to intrinsic (non-modifiable) and/or extrinsic (modifiable) factors of ACL injury.

EVIDENCE ACQUISITION

Research of the studies was conducted until September 2018 without publication data limitation or language restriction on the following databases: PubMed/MEDLINE, Scopus, ISI, EXCERPTA.

EVIDENCE SYNTHESIS

To date, evidence from the literature suggests that the risk of ACL injury is multifactorial and involves biomechanical, anatomical, hormonal, and neuromuscular factors. Despite this relative complexity, the mechanisms of injury are well known and rationally classified into two categories: mechanisms of injury based on contact or on non-contact with another player, with the non-contact injury mechanisms clearly prevailing over the mechanisms of contact injury. One of the most frequent biomechanical risk factors, associated with ACL non-contact injury, is represented by the valgus knee in the pivoting and cutting movements and in the landing phase after jumping. Gender-related risk factors show female populations to have a higher predisposition to ACL injury than males However, there are still some theoretical and practical aspects that need further investigation such as; genetic risks together with the role of estrogen and progesterone receptors in female populations, and the in-vivo interaction shoe-playing surface. In particular, the genetic risk factors of ACL lesion seem to be an interesting and promising field of investigation, where considerable progress has still to be made.

CONCLUSIONS

This narrative review provides an insight into the risk factors of ACL injury that could be used by practitioners for preventing injury in football (soccer).

The VEGFA gene and anterior cruciate ligament rupture risk in the Caucasian population

The aim of the present study was to analyse VEGFA rs699947, rs1570360, and rs2010963 polymorphisms with susceptibility to anterior cruciate ligament rupture (ACLR) in a Polish population. The study included 412 physically active Caucasian participants. The study group consisted of 222 individuals with surgically diagnosed primary ACLR qualified for ligament reconstruction (ACLR group). The control group consisted of 190 apparently healthy participants without any history of ACLR (CON group). Three polymorphisms within the VEGFA (rs699947, rs1570360, and rs2010963) gene were chosen for investigation due to their significance in the angiogenesis signalling pathway and previous associations with risk of ACLRs. Both single-locus and haplotype-based analyses were conducted. No significant differences in the allele and genotype frequency distributions were noted for the rs699947 and rs1570360 polymorphisms. In contrast, rs2010963 was associated with risk of ACLR in the codominant (p=0.047) and recessive model (p=0.017). In the latter, the CC genotype was overrepresented among individuals with ACL rupture (23.4% vs 14.2%, OR=1.85 [1.11-3.08]). Two VEGFA haplotypes were associated with ACLR under the additive (global score=11.39, p=0.022) and dominant model (global score=11.61, p=0.020). The [C;G;G] haplotype was underrepresented in the ACLR group (52.2% vs. 60.3%), whereas the [C;G;C] haplotype was overrepresented (2.9% vs 0.5%). The results obtained suggest a potential correlation between the VEGFA rs2010963 polymorphism and ACLR risk, suggesting that harbouring this specific C allele may be an unfavourable risk factor for a knee injury in Caucasian participants from Poland.

Are IL1B, IL6 and IL6R Gene Variants Associated with Anterior Cruciate Ligament Rupture Susceptibility?

Cytokines, such as interleukins, are crucial in regulating critical cell signaling pathways as well as being major contributors to inflammatory response and are upregulated during ligament and tendon injuries. The genes encoding key interleukins, such as IL1B and IL6 as well as interleukin receptor IL6R, were chosen as candidate genes for association with soft tissue injuries. The aim of the case-control study was to verify the hypothesis that sequence variants rs1143627, rs16944, rs1800795, rs2228145 in the IL1B, IL6 and IL6R genes are associated with ACL rupture susceptibility in a Polish population. Among four analyzed SNPs, the rs1800795 IL6 gene polymorphism was found to be the only one significantly associated with ACL rupture (p = 0.010, p = 0.022, p = 0.004 for codominant, recessive and overdominant models, respectively; odds ratio = 1.74, 95% CI 1.08-2.81, sex adjusted p = 0.032 for recessive model). With reference to the other analyzed polymorphisms, we failed to show significant differences in the genotype and allele frequencies for IL6R rs2228145as well as IL1B rs16944 and rs1143627 (analyzed alone or in haplotype combination) between the ACL rupture group and the healthy control group among Polish participants. Due to the nature of case-control studies, the results of this study need to be confirmed in independent studies with larger sample sizes.

No Association Between Risk of Anterior Cruciate Ligament Rupture and Selected Candidate Collagen Gene Variants in Female Elite Athletes From High-Risk Team Sports

BACKGROUND

Several single-nucleotide variants (SNVs) in collagen genes have been reported as predisposing factors for anterior cruciate ligament (ACL) tears. However, the evidence is conflicting and does not support a clear association between genetic variants and risk of ACL ruptures.

PURPOSE

To assess the association of previously identified candidate SNVs in genes encoding for collagen and the risk of ACL injury in a population of elite female athletes from high-risk team sports.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 851 female Norwegian and Finnish elite athletes from team sports were included from 2007 to 2011. ACL injuries acquired before inclusion in the cohort were registered by interview. The participants were followed prospectively through 2015 to record new complete ACL injuries. Six selected SNVs were genotyped ( COL1A1: rs1800012, rs1107946; COL3A1: rs1800255; COL5A1: rs12722, rs13946; COL12A1: rs970547).

RESULTS

No associations were found between ACL rupture and the SNVs tested.

CONCLUSION

The study does not support a role of the 6 selected SNVs in genes encoding for collagen proteins as risk factors for ACL injury.

CLINICAL RELEVANCE

Genetic profiling to identify athletes at high risk for ACL rupture is not yet feasible.

Genetic Variants and Anterior Cruciate Ligament Rupture: A Systematic Review

Background

Studies have shown a familial predisposition for anterior cruciate ligament (ACL) rupture and have been followed by genetic-association studies on polymorphisms in candidate genes in recent years. To date, no systematic review with a best-evidence synthesis has evaluated the influence of genetics on this devastating knee injury.

Objective

Our objective was to evaluate the association between genetic variants and ACL rupture.

Methods

We performed an extensive search in Embase, MEDLINE, Web of Science, Scopus, PubMed Publisher, Cochrane Register of Clinical Trials, and Google scholar up to 24 August 2015. Studies were eligible if they met the following inclusion criteria: (1) design was a case–control study, retrospective or prospective follow-up study, or a randomized controlled trial (RCT); (2) the study examined the association between a genetic variant and ACL rupture in both an ACL and a control group. We determined the risk of bias for all included studies.

Results

We included a total of 16 studies (eight at high risk of bias and eight with an unclear risk) that examined 33 different DNA variants. Conflicting evidence was found for the COL1A1 rs1800012 and COL3A1 rs1800255 variants, whereas limited evidence was found for no association of the COL5A1 rs12722 and rs13946 and COL12A1 rs970547 variants (all encoding collagen). Evidence was insufficient to draw conclusions as to whether any other genetic variant identified in this review had any association with ACL rupture.

Conclusions

More research is needed to support a clear association between ACL rupture and genetic variants. Genome-wide studies are recommended for exploring more potential genetic variants. Moreover, large prospective studies are needed to draw robust conclusions.

Risk factors of anterior cruciate ligament injury in football players: a systematic review of the literature

BACKGROUND

The ACL lesion represents one of the most dramatic injuries in a sportsman's career. There are many injury risk factors related to intrinsic, or non-modifiable, and extrinsic, or modifiable, factors. In literature at today current evidence suggests that ACL injury risk is multifactorial and involves biomechanical, anatomical, hormonal and neuromuscular factors.

PURPOSE

To perform a systematic review of the literature concerning the ACL injury risk factors in soccer.

CONCLUSION

The injury risk factors show a low level of evidence, further studies in the field are needed.

STUDY DESIGN

Systematic review.

Are genes encoding proteoglycans really associated with the risk of anterior cruciate ligament rupture?

Proteoglycans are considered integral structural components of tendon and ligament and have been implicated in the resistance of compressive forces, collagen fibrillogenesis, matrix remodelling and cell signalling. Several sequence variants within genes encoding proteoglycans were recently implicated in modulating anterior cruciate ligament ruptures (ACLR). This study aimed to test the previously implicated variants in proteoglycan and vascular epithelial growth factor encoding genes with risk of ACLR in a population from Poland. A case control genetic association study was conducted using DNA samples from 143 healthy participants without a history of ACL injuries (99 male and 44 females) (CON group) and 229 surgically diagnosed ACLR participants (158 males and 71 females). All samples were genotyped for the ACAN: rs1516797, BGN: rs1042103, rs1126499, DCN: rs516115 and VEGFA: rs699947 variants. Main findings included the (i) ACAN rs1516797 G/T genotype which was underrepresented in the CON group (CON: 36%, n=52, ACLR: 49%, n=112, p=0.017, OR=1.68, 95% CI 1.09 to 2.57) when all participants were investigated and (ii) the BGN rs1042103 A allele was significantly under-represented in the male CON group compared to the male ACLR group (CON: 39%, n=78, ACLR: 49%, n=156, p=0.029, OR=1.5, 95% CI 1.05 to 2.15). Furthermore, BGN inferred haplotypes were highlighted with altered ACLR susceptibility. Although the study implicated the ACAN and BGN genes (combination of genotype, allele and haplotype) in modulating ACLR susceptibility, several differences were noted with previous published findings.

Association of ACL tears and single nucleotide polymorphisms in the collagen 12 A1 gene in the Indian population - a preliminary case-control study

BACKGROUND

Genetic predisposition to ACL tears has received tremendous interest in the past few years with many SNPs of different genes being linked to ACL tear.

STUDY OBJECTIVES

To examine if specific sequence variants in COL12A1 gene are associated with ACL tears in Indian population.

STUDY DESIGN

Case-control study.

MATERIALS AND METHODS

50 patients with surgically diagnosed ACL tear and 52 healthy, age-matched controls without any ligament/tendon injuries were genotyped for rs970547 and rs240736 SNPs using real time PCR method.

RESULTS

The AG and GG genotypes were significantly under-represented in study group patients in rs970547 region (p=0.0361). However, there was no significant difference in genotype/allele frequencies in the rs240736 region.

CONCLUSIONS

The COL12A1 rs970547 SNP is associated with ACL tears in the Indian population. However, these results need to be validated further so that predisposed individuals can be screened in the future for counselling and intervention.

LEVEL OF EVIDENCE

III.

Is There a Genetic Predisposition to Anterior Cruciate Ligament Tear? A Systematic Review

BACKGROUND

Injuries to the anterior cruciate ligament (ACL) are among the most common knee ligament injuries and frequently warrant reconstruction. The etiopathogenesis of these injuries has focused mainly on mechanism of trauma, patient sex, and anatomic factors as predisposing causes. Several genetic factors that could predispose to an ACL tear have recently been reported.

PURPOSE

This systematic review summarizes the current evidence for a genetic predisposition to ACL tears. The principal research question was to identify genetic factors, based on the available literature, that could predispose an individual to an ACL tear.

STUDY DESIGN

Systematic review.

METHODS

The PubMed, EMBASE, Cochrane, and HuGE databases were searched; the search was run from the period of inception until June 21, 2015. A secondary search was performed by screening the references of full-text articles obtained and by manually searching selected journals. Articles were screened with prespecified inclusion criteria. The quality of studies included in the review was assessed for risk of bias by 2 reviewers using the Newcastle-Ottawa Scale.

RESULTS

A total of 994 records were identified by the search, out of which 17 studies (16 case-control studies and 1 cross-sectional study) were included in the final review. Two studies observed a familial predisposition to an ACL tear. Fourteen studies looked at specific gene polymorphisms in 20 genes, from which different polymorphisms in 10 genes were positively associated with an ACL tear. In addition to these polymorphisms, 8 haplotypes were associated with ACL tear. One study looked at gene expression analysis.

CONCLUSION

Although specific gene polymorphisms and haplotypes have been identified, it is difficult to come to a conclusion on the basis of the existing literature. Several sources of bias have been identified in these studies, and the results cannot be extrapolated to the general population. More studies are needed in larger populations of different ethnicities. Gene-gene interactions and gene expression studies in the future may delineate the exact role of these gene polymorphisms in ACL tears.