A systematic review of association studies of common variants associated with idiopathic congenital talipes equinovarus (ICTEV) in humans in the past 30 years

COL1A1 regulates the apoptosis of embryonic stem cells by mediating the PITX1/TBX4 signaling

PURPOSE

The purpose of this study is to explore the regulatory function of COL1A1 against the apoptosis of embryonic stem cells (ESCs) and the potential function in congenital talipes equinovarus (CTEV).

METHODS

Muscle tissues were collected from 20 children with CTEV and 20 children without CTEV, followed by detecting the expression of COL1A1 using the RT-PCR method. COL1A1 was knocked down in H1 and H9 human ESCs using the RNA interference technology, followed by determining the level of COL1A1, PITX1, TBX4, HOXD10, Fas, FasL, and Bax using the Western blotting assay.

RESULTS

COL1A1 was found markedly upregulated in muscle tissues of CTEV children. In H1 and H9 human ESCs, compared to the empty vector, COL1A1, PITX1, TBX4, HOXD10, Fas, FasL, and Bax were found notably downregulated after transfected with the siRNA targeting COL1A1.

CONCLUSION

COL1A1 induced the apoptosis of ESCs by mediating the PITX1/TBX4 signaling and might be a potential target for treating CTEV.

What is New in Pediatric Orthopaedic: Basic Science

BACKGROUND

An understanding of musculoskeletal basic science underpins most advancements in the field of orthopaedic surgery. Knowledge of biomechanics, genetics, and molecular pathways is integral to the understanding of the pathophysiology of disease and guides novel treatment options to improve patient outcomes. The purpose of this review is to provide a comprehensive and current overview of musculoskeletal basic science relevant to pediatric orthopaedic surgery.

METHODS

Comprehensive Pubmed database searches were performed for all English language articles published between January 2016 and November 2021 using the following search terms: basic science, pediatric orthopaedics, fracture, trauma, spine, scoliosis, DDH, hip dysplasia, Perthes, Legg-Calve-Perthes, clubfoot, and sports medicine. Inclusion criteria focused on basic science studies of pediatric orthopaedic conditions. Clinical studies or case reports were excluded. A total of 3855 articles were retrieved. After removing duplicates and those failing to meet our inclusion criteria, 49 articles were included in the final review.

RESULTS

A total of 49 papers were selected for review based on the date of publication and updated findings. Findings are discussed in the subheadings below. Articles were then sorted into the following sub-disciplines of pediatric orthopaedics: spine, trauma, sports medicine, hip, and foot.

CONCLUSIONS

With this review, we have identified many exciting developments in pediatric orthopaedic trauma, spine, hip, foot, and sports medicine that could potentially lead to changes in disease management and how we think of these processes.

LEVEL OF EVIDENCE

Level V.

Genetic Role in Recurrence of Idiopathic CTEV: A Systematic Review

Background

Congenital Talipes Equinovarus (CTEV) is a multitude of deformities involving equinus, varus, adductus, and cavus deformities. Clubfoot affects 1 in every 1000 infants born worldwide, with various incidences according to geographical areas. It has been previously hypothesized that the possible genetic role in Idiopathic CTEV (ICTEV) might have a treatment-resistant phenotype. However, the genetic involvement in recurrent ICTEV cases is yet to be determined.

Aim

To systematically review existing literature regarding the discovery of genetic involvement in recurrent ICTEV to date to further understand the etiology of relapse.

Methods

A comprehensive search was performed on medical databases, and the review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A comprehensive search was performed on several medical databases: PubMed (MEDLINE), Scopus, the Cochrane Library, and European PMC on May 10, 2022. We included studies reporting patients with recurring idiopathic CTEV or CTEV of unknown cause after treatment, reporting whole-genetic sequencing, whole-exome sequencing, Polymerase Chain Reaction, or Western blot analysis as methods of genetic analysis (intervention) and providing results of idiopathic CTEV genetic involvement. Non-English studies, literature reviews, and irrelevant articles were excluded. Quality and risk of bias assessments were performed using Newcastle-Ottawa Quality Assessment Scale for non-randomized studies where appropriate. The authors discussed data extracted with the primary outcome of gene(s) frequency being reported of their involvement in recurrent ICTEV cases.

Results

Three pieces of literature were included in this review. Two studies analyzed the genetic involvement in CTEV occurrence, while one analyzed the protein types found.

Discussion

With included studies of less than five, we could not perform other forms of analysis apart from qualitatively.

Conclusion

The rarity of literature exploring the genetic etiology of recurrent ICTEV cases has been reflected in this systematic review, giving opportunities for future research.

Congenital talipes equinovarus: A literature review

Congenital talipes equinovarus (CTEV) is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus. The etiology of CTEV is poorly understood, despite its incidence ranging from 0.76 to 3.49 cases per 1000 live births in Indonesia. CTEV involves the fixation of the foot in the adducts, varus, and equinus with concurrent soft tissue anomalies. Despite advances in treatment, disability often persists. Theoretical models have been proposed for neurological, vascular, connective tissue, bone, and muscular causes; however, the currently available data suggests that mild cases are associated with intrauterine position. CTEV's etiology appears to involve a hereditary component, as its prevalence varies by ethnic group. Genetic factors have been identified in 24–50% of cases, depending on the community studied. Based on a complex segregation analysis, the most plausible inheritance pattern is a single large-effect gene interacting with a polygenic background.

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CTEV is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus.

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In Indonesia, its incidence ranges from 0.76 to 3.49 cases per 1000 live births.

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Genetic factors have been identified in 24–50% of cases, depending on the community studied.

Regulation of COL1A2, AKT3 genes, and related signaling pathway in the pathology of congenital talipes equinovarus

Congenital talipes equinovarus (CTEV) is one of the most common congenital limb defects in children, which is a multifactorial and complex disease that associates with many unknown genetic, social-demographic, and environmental risk factors. Emerging evidence proved that gene expression or mutation might play an important role in the occurrence and development of CTEV. However, the underlying reasons and involved mechanisms are still not clear. Herein, to probe the potential genes and related signaling pathways involved in CTEV, we first identified the differentially expressed genes (DEGs) by mRNA sequencing in pediatric patients with CTEV compared with normal children. The gene of COL1A2 was upregulated, and AKT3 was downregulated at the transcriptional level. Western blot and quantitative polymerase chain reaction (qRT-PCR) results also showed that the expression of COL1A2 in CTEV was enhanced, and the AKT3 was decreased. Furthermore, the COL1A2 Knock-in (+COL1A2) and AKT3 Knock-out (-AKT3) transgenic mice were used to verify the effects of these two genes in the CTEV, and the results of which showed that both COL1A2 and AKT3 were closely related to the CTEV. We also investigated the effect of the PI3K-AKT3 signaling pathway in CTEV by measuring the relative expression of several key genes using Western blot and qRT-PCR. In line with the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis data, the PI3K-AKT3 signaling pathway might play a potentially important role in the regulation of pathological changes of CTEV. This study will provide new ideas for the mechanism investigation and prenatal diagnosis of CTEV.

The etiology of idiopathic congenital talipes equinovarus: a systematic review

Background

Also known as clubfoot, idiopathic congenital talipes equinovarus (ICTEV) is the most common pediatric deformity and occurs in 1 in every 1000 live births. Even though it has been widely researched, the etiology of ICTEV remains poorly understood and is often described as being based on a multifactorial genesis. Genetic and environmental factors seem to have a major role in the development of this disease. Thus, the aim of this review is to analyze the available literature to document the current evidence on ICTEV etiology.

Methods

The literature on ICTEV etiology was systematically reviewed using the following inclusion criteria: studies of any level of evidence, reporting clinical or preclinical results, published in the last 20 years (1998–2018), and dealing with the etiology of ICTEV.

Results

A total of 48 articles were included. ICTEV etiology is still controversial. Several hypotheses have been researched, but none of them are decisive. Emerging evidence suggests a role of several pathways and gene families associated with limb development (HOX family; PITX1-TBX4), the apoptotic pathway (caspases), and muscle contractile protein (troponin and tropomyosin), but a major candidate gene has still not been identified. Strong recent evidence emerging from twin studies confirmed major roles of genetics and the environment in the disease pathogenesis.

Conclusions

The available literature on the etiology of ICTEV presents major limitations in terms of great heterogeneity and a lack of high-profile studies. Although many studies focus on the genetic background of the disease, there is lack of consensus on one or multiple targets. Genetics and smoking seem to be strongly associated with ICTEV etiology, but more studies are needed to understand the complex and multifactorial genesis of this common congenital lower-limb disease.

The recurrence risk of genetic complex diseases

Complex inherited diseases affected by an interaction between collective effects of the genotype at one or multiple loci either to increase or to lower susceptibility to disease, combined with a variety of environmental exposures that may trigger, accelerate, exacerbate, or protect against the disease process. The new aspects of genetic techniques have been opened for diagnosis and analysis of inherited disorders. While appropriate Mendelian laws is applied to estimate the recurrence risk of single gene diseases, using empirical recurrence risks are the most important and available method to evaluate pedigree of complex (multifactorial), chromosomal, and unknown etiology disorders. Although, generally, empirical recurrent risks are not accurate, either because of the difference of gene frequencies and environmental factors among populations or heterogeneity of disease; using results of plenty family population studies, computerized estimating programs, genotyping technologies, and Genome-wide association studies (GWASs) of single nucleotide polymorphisms (SNPs), can make it possible nowadays to estimate these risks. The specific family situation and importance recurrence risks of some common complex genetic diseases will be presented in this review and some important multifactorial disorders’ recurrence risks will be summarized to help genetic counselors for supporting families and representing better view of genetic disorders.