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Open Heart Apr 2022This study summarises the diagnostic validity and clinical utility of genetic testing for patients with hypertrophic cardiomyopathy (HCM) and their at-risk relatives. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
This study summarises the diagnostic validity and clinical utility of genetic testing for patients with hypertrophic cardiomyopathy (HCM) and their at-risk relatives.
METHODS
A systematic search was performed in PubMed (MEDLINE), Embase, CINAHL and Cochrane Central Library databases from inception through 2 March 2020. Subgroup and sensitivity analyses were prespecified for individual sarcomere genes, presence/absence of pathogenic variants, paediatric and adult cohorts, family history, inclusion of probands, and variant classification method. Study quality was assessed using the Newcastle-Ottawa tool.
RESULTS
A total of 132 articles met inclusion criteria. The detection rate based on pathogenic and likely pathogenic variants was significantly higher in paediatric cohorts compared with adults (56% vs 42%; p=0.01) and in adults with a family history compared with sporadic cases (59% vs 33%; p=0.005). When studies applied current, improved, variant interpretation standards, the adult detection rate significantly decreased from 42% to 33% (p=0.0001) because less variants met criteria to be considered pathogenic. The mean difference in age-of-onset in adults was significantly earlier for genotype-positive versus genotype-negative cohorts (8.3 years; p<0.0001), versus cohorts (8.2 years; p<0.0001) and individuals with multiple versus single variants (7.0 years; p<0.0002). Overall, disease penetrance in adult cohorts was 62%, but differed significantly depending on if probands were included or excluded (73% vs 55%; p=0.003).
CONCLUSIONS
This systematic review and meta-analysis is the first, to our knowledge, to collectively quantify historical understandings of detection rate, genotype-phenotype associations and disease penetrance for HCM, while providing the answers to important routine clinical questions and highlighting key areas for future study.
Topics: Cardiomyopathy, Hypertrophic; Child; Genetic Association Studies; Genetic Testing; Genotype; Humans; Penetrance
PubMed: 35387861
DOI: 10.1136/openhrt-2021-001815 -
Neuro-oncology Jun 2014Association studies of germline DNA repair single nucleotide polymorphisms (SNPs) and glioma risk have yielded inconclusive results. We therefore performed a systematic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Association studies of germline DNA repair single nucleotide polymorphisms (SNPs) and glioma risk have yielded inconclusive results. We therefore performed a systematic review and meta-analysis of studies investigating this association.
METHODS
We identified 27 eligible studies investigating 105 SNPs in 42 DNA repair genes. Of these, 10 SNPs in 7 genes were analyzed in at least 4 studies and were therefore included in our meta-analysis. The meta-analysis was performed for homozygote comparison, heterozygote comparison, and dominant and recessive models by applying a fixed- or random-effects model. The funnel and forest plots were created using RevMan software.
RESULTS
We found that SNPs rs3212986 (odds ratio [OR] = 1.35 (1.08-1.68), P = .008), rs13181 (OR = 1.18 (1.06-1.31), P = .002), and rs25487 (OR = 1.12 (1.03-1.22), P = .007) in DNA repair genes ERCC1, ERCC2 (XPD), and XRCC1 may increase the risk of glioma, while polymorphisms rs1136410 (OR = 0.78 (0.68-0.89), P = .0004) and rs12917 (OR = 0.84 (0.73-0.96), P = .01) in PARP1(ADPRT) and MGMT are associated with decreased susceptibility to glioma. No evidence of significant associations between ERCC2 rs1799793, OGG1 rs1052133, XRCC1 rs25489, XRCC1 rs1799782, or XRCC3 rs861539 and risk of glioma was observed.
CONCLUSION
This study provides evidence that DNA repair genes ERCC1, ERCC2, and XRCC1 might be low-penetrance glioma-risk genes, while MGMT and PARP1 polymorphisms may confer protection against glioma.
Topics: Brain Neoplasms; DNA Repair; Genetic Association Studies; Glioma; Humans; Polymorphism, Single Nucleotide; Risk Factors
PubMed: 24500421
DOI: 10.1093/neuonc/nou003 -
Brain and Behavior Jun 2023Primary generalized dystonia due to the DYT1 gene is an autosomal dominant disorder caused by a GAG deletion on chromosome 9q34. It is a well-defined, genetically... (Review)
Review
BACKGROUND
Primary generalized dystonia due to the DYT1 gene is an autosomal dominant disorder caused by a GAG deletion on chromosome 9q34. It is a well-defined, genetically proven, isolated dystonia syndrome. However, its pathophysiology remains unclear.
OBJECTIVES
This study was aimed at profiling the functional neuroimaging findings in DYT1 dystonia and harmonizing the pathophysiological implications for DYT1 dystonia from the standpoint of different neuroimaging techniques.
METHODS
A systematic review was conducted using identified studies published in English from Medline, PsycINFO, Embase, CINAHL, and the Cochrane Database of Systematic Reviews (CDSR), between 1985 and December 2019 (PROSPERO protocol CRD42018111211).
RESULTS
All DYT1 gene carriers irrespective of clinical penetrance have reduced striatal GABA, dopamine receptors and increased metabolic activity in the lentiform nucleus, supplementary motor area, and cerebellum in addition to an abnormal cerebellothalamocortical pathway. Nonmanifesting carriers on the other hand have a disruption of the distal (thalamocortical) segment and have larger putaminal volumes than manifesting carriers and healthy controls. Activation of the midbrain, thalamus, and sensorimotor cortex was only found in the manifesting carriers.
CONCLUSIONS
Therefore, we propose that DYT1 dystonia is a cerebellostriatothalamocortical network disorder affecting either the structure or function of the different structures or nodes in the network.
Topics: Humans; Dystonia; Dystonic Disorders; Molecular Chaperones; Neuroimaging
PubMed: 37165749
DOI: 10.1002/brb3.3023 -
Applied Health Economics and Health... Oct 2015Hereditary haemochromatosis (HH) is a common genetic condition amongst people of northern European heritage. HH is associated with increased iron absorption leading to... (Review)
Review
BACKGROUND
Hereditary haemochromatosis (HH) is a common genetic condition amongst people of northern European heritage. HH is associated with increased iron absorption leading to parenchymal organ damage and multiple arthropathies. Early diagnosis and treatment prevents complications. Population screening may increase early diagnosis, but no programmes have been introduced internationally: a paucity of health economic data is often cited as a barrier.
OBJECTIVE
To conduct a systematic review of all health economic studies in HH.
METHODS
Studies were identified through electronic searching of economic/biomedical databases. Any study on HH with original economic component was included. Study quality was formally assessed. Health economic data were extracted and analysed through narrative synthesis.
RESULTS
Thirty-eight studies met the inclusion criteria. The majority of papers reported on costs or cost effectiveness of screening programmes. Whilst most concluded screening was cost effective compared with no screening, methodological flaws limit the quality of these findings. Assumptions regarding clinical penetrance, effectiveness of screening, health-state utility values (HSUVs), exclusion of early symptomatology (such as fatigue, lethargy and multiple arthropathies) and quantification of costs associated with HH were identified as key limitations. Treatment studies concluded therapeutic venepuncture was the most cost-effective intervention.
CONCLUSIONS
There is a paucity of high-quality health economic studies relating to HH. The development of a comprehensive HH cost-effectiveness model utilising HSUVs is required to determine whether screening is worthwhile.
Topics: Cost-Benefit Analysis; Health Care Costs; Hemochromatosis; Humans; Mass Screening
PubMed: 26255179
DOI: 10.1007/s40258-015-0189-y -
Journal of Neurosurgery. Spine Apr 2024Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is... (Review)
Review
OBJECTIVE
Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is considered largely sporadic-however, there exists growing evidence of transmissible genetic underpinnings. The purpose of this systematic review of all familial studies of CM was to investigate the existence of an inherited component and provide recommendations to manage and monitor at-risk family members.
METHODS
This paper includes the following: 1) a unique case report of dizygotic twins who presented at the Toronto Western Hospital Spinal Cord Clinic with symptomatic CM type 1 (CM-1) and syringomyelia; and 2) a systematic review of familial CM. The EMBASE and MEDLINE databases were searched on June 27, 2023, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only articles in the English language concerning the diagnosis of CM in > 1 human family member presented as a case study, case series, or literature review were included.
RESULTS
Among the 29 articles included in the final analysis, a total of 34 families with CM were analyzed. An average of 3 cases of CM were found per family among all generations. Eighty-one cases (88%) reported CM-1, whereas the other 11 (12%) cases reported either CM-0, CM-1.5, or tonsillar ectopia. A syrinx was present in 37 (54%) cases, with 14 (38%) of these patients also reporting a skeletal abnormality, the most common comorbidity. Most family members diagnosed with CM were siblings (18; 35%), followed by monozygotic twins/triplets (12; 23%).
CONCLUSIONS
Patients most often presented with headaches, sensory disturbances, or generalized symptoms. Overall, there exists mounting evidence for a hereditary component of CM. It is unlikely to be explained by a classic mendelian inheritance pattern, but is rather a polygenic architecture influenced by variable penetrance, cosegregation, and entirely nongenetic factors. For first-degree relatives of those affected by CM, the authors' findings may influence clinicians to conduct closer clinical and radiographic monitoring, promote patient education, and consider earlier genetic testing.
PubMed: 38608294
DOI: 10.3171/2024.1.SPINE231277 -
Circulation. Genomic and Precision... Jun 2022Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a complex cardiomyopathy with autosomal dominant inheritance and age-related incomplete penetrance,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a complex cardiomyopathy with autosomal dominant inheritance and age-related incomplete penetrance, characterized by a high risk of sudden cardiac death. Recent professional consensus guidelines recommend clinical cardiac lifelong serial screening for at-risk family members refined only by age, but family genotype might influence necessary screening. Although numerous studies report prevalence of disease and arrhythmia in family members and explore predictors of penetrance and arrhythmic risk, a systematic review consolidating this evidence is lacking.
METHODS
We searched Medline (PubMed), Embase, The Cochrane Library, and Web of Science for studies that reported prevalence of (1) diagnosis of ARVC per 2010 Task Force Criteria and/or (2) sustained ventricular arrhythmias (VA) in at least 10 family members of definite patients with ARVC.
RESULTS
We identified 41 studies, including 36 that reported diagnosis by Task Force Criteria and 22 VA. Meta-analysis of 1359 family members, from 13 unique cohorts showed an average prevalence estimate of 25% for diagnosis as per Task Force Criteria (95% CI, 0.15-0.35, I96.44%). Overall prevalence of VA among gene-positive family members was 18% (95% CI, 0.13-0.23, I=33.25%) in 7 independent studies (n=597). Family genotype was a significant risk factor for diagnosis of both ARVC (odds ratio, 6.91 [95% CI, 1.27-37.70]; =0.0005) and VA (odds ratio, 13.62 [95% CI, 0.91-204.13]; =0.06). Male gender was not associated with disease prevalence (odds ratio, 1.18 [95% CI, 0.72-1.95]; =0.42) or VA (odds ratio, 0.81 [95% CI, 0.51-1.29]; =0.91).
CONCLUSIONS
The prevalence of ARVC and VA in at-risk family members differs significantly based on family genotype. Although recent recommendations provide a guideline based only on age, we propose screening every 1 to 2 years for gene-positive family members and every 3 to 5 years for first-degree relatives of gene-elusive cases, as long as they are asymptomatic and not athletes.
Topics: Arrhythmias, Cardiac; Arrhythmogenic Right Ventricular Dysplasia; Child, Preschool; Death, Sudden, Cardiac; Family; Humans; Infant; Male; Prevalence
PubMed: 35579515
DOI: 10.1161/CIRCGEN.121.003530 -
Gastric Cancer : Official Journal of... Sep 2012Hereditary diffuse gastric cancer (HDGC) is a familial cancer syndrome specifically associated with germline mutations to the E-cadherin (CDH1) gene. HDGC is... (Review)
Review
BACKGROUND
Hereditary diffuse gastric cancer (HDGC) is a familial cancer syndrome specifically associated with germline mutations to the E-cadherin (CDH1) gene. HDGC is characterized by autosomal dominance and high penetrance and a high cumulative risk for advanced gastric cancer. Our purpose in this study was to identify and synthesize findings from all articles on: (1) current recommendations for CDH1 screening and prophylactic gastrectomy; (2) CDH1 testing results in HDGC patients; and (3) prophylactic gastrectomy results in HDGC patients.
METHODS
Systematic electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1985 to 2009.
RESULTS
Seventy articles were included in this review. Among patients with a positive family history of gastric cancer, 1085 were screened from 454 families, and 38.4% tested positive. Mutation-positive families also had a considerable family history of breast and colon cancer. Of the 322 patients screened for CDH1 mutations by current HDGC screening criteria, 29.2% tested positive. Among the 76.8% of patients who underwent prophylactic gastrectomy following positive CDH1 test results, 87.0% had positive final histopathology results and 64.6% had signet ring cells identified. Some of the patients with negative final histopathology results had opted to undergo prophylactic gastrectomy prior to CDH1 testing, and were ultimately found to be negative for CDH1 mutations.
CONCLUSION
CDH1 mutation testing in families with a history of gastric cancer and prophylactic gastrectomy in mutation-positive patients are recommended for the management of HDGC.
Topics: Cadherins; Gastrectomy; Genetic Testing; Germ-Line Mutation; Humans; Stomach Neoplasms
PubMed: 22160243
DOI: 10.1007/s10120-011-0116-3 -
European Journal of Medical Genetics Feb 2022The 22q11 region is prone to generating recurring Copy Number Variations (CNVs) as a result of the large numbers of Low Copy Repeats (LCRs). Typical duplications... (Review)
Review
The 22q11 region is prone to generating recurring Copy Number Variations (CNVs) as a result of the large numbers of Low Copy Repeats (LCRs). Typical duplications encompass the LCR-A-to-D region but atypical duplications of various sizes have also been reported. These duplications are responsible for highly variable phenotypes with incomplete penetrance and expressivity, which is challenging for adequate genetic counselling, especially in the prenatal period. To better delineate prenatal phenotypes associated with these CNVs, we report here a clinical and molecular description of twelve cases (9 foetuses and 3 deceased new-borns babies) carrying recurrent 22q11 duplications (diagnosed via aCGH), along with a review of the existing literature. 22q11 duplications were inherited from an apparently healthy parent in almost 60% of the cases. Other CNVs were diagnosed for 8% of the cases. Increased nuchal translucency and cardiac anomalies (CHD) were the most prominent phenotypes observed, along with mild renal and skeletal anomalies. Duplications encompassing the LCR-C-to-D region (and the CRKL gene) seemed more likely to generate CHDs and renal malformations. Cleft lip/palate were observed in foetuses with duplications encompassing the LCR-A-to-B region or the SPECC1L gene, as previously suggested. However, genotype-phenotype correlations remain difficult to ascertain. Second-hit point variants, epigenetic or environmental variations could play a role in the phenotypic variability of 22q11 duplications, but remain a challenge for assessment in the short period of pregnancy.
Topics: Abnormalities, Multiple; Adaptor Proteins, Signal Transducing; Chromosome Duplication; Chromosomes, Human, Pair 22; DiGeorge Syndrome; Female; Fetus; Humans; Infant, Newborn; Male; Phenotype; Phosphoproteins
PubMed: 35026468
DOI: 10.1016/j.ejmg.2022.104422 -
Familial Cancer Oct 2016Multiple endocrine neoplasia type 2A (MEN2A) may be rarely associated with cutaneous lichen amyloidosis (CLA), a skin lesion located in the interescapular region. Here,... (Review)
Review
Multiple endocrine neoplasia type 2A (MEN2A) may be rarely associated with cutaneous lichen amyloidosis (CLA), a skin lesion located in the interescapular region. Here, we describe 3 MEN2A-related CLA kindred and perform a systematic review (SR) of the literature on clinical, biochemical and molecular characteristics of MEN2A-related CLA patients. Thirty-eight patients with MEN2A-related CLA followed at our institution were evaluated. The median age at MEN2A diagnosis in our cohort was 25 (13-41) years, 68 % were women and all harbored codon 634 RET mutations. The literature search resulted in 20 publications that contributed with 25 MEN2A families and 214 individuals. The mean age of MEN2A diagnosis was 31 ± 17 years, with 77 % women. The mean age reported by patients to initial skin lesion suggestive to CLA was 20 ± 13 years. All but two kindred harbored mutations at codon 634: C634R 7 kindred (35 %), C634Y 5 kindred (25 %), C634W 3 kindred (15 %), C634G 1 kindred (5 %), V804M 1 kindred (5 %) and S891A 1 kindred (5 %). Most interesting, the standardized CLA prevalence was higher in women (2.3/1.0, P < 0.005). The overall reported prevalence of medullary thyroid carcinoma, CLA, pheochromocytoma and hyperparathyroidism was 94, 51, 30 and 16 %, respectively. SR of literature indicates that MEN2A-related CLA is more frequent in women and presents a high penetrance, being the second most frequent manifestation of the syndrome, preceded only by MTC.
Topics: Adolescent; Adult; Amyloidosis; Female; Humans; Male; Multiple Endocrine Neoplasia Type 2a; Pedigree; Proto-Oncogene Proteins c-ret; Skin Neoplasms; Young Adult
PubMed: 26920351
DOI: 10.1007/s10689-016-9892-6 -
JAMA Neurology Apr 2015In the past 2 years, 3 genes (SLC20A2, PDGFRB, and PDGFB) were identified as causative of primary familial brain calcification (PFBC), enabling genotype-specific... (Review)
Review
IMPORTANCE
In the past 2 years, 3 genes (SLC20A2, PDGFRB, and PDGFB) were identified as causative of primary familial brain calcification (PFBC), enabling genotype-specific phenotyping.
OBJECTIVES
To provide a systematic literature review on the neuroimaging and clinical phenotype of genetically confirmed PFBC and summarize known pathophysiological mechanisms, to improve and harmonize future phenotype description and reporting by addressing data gaps, and to develop uniform definitions for clinical characterization.
EVIDENCE REVIEW
We systematically searched the MEDLINE database among articles published from January 1, 2012, through May 31, 2014, for the 3 genes and selected 25 articles from all records (n=75) and from sources cited in the reference lists. Only genetically confirmed cases with individual clinical information were included, leaving 15 reports. Predefined categories for data extraction were different neurologic and psychiatric symptoms, imaging results, and age at onset (AAO). We also assessed availability of information to estimate possible bias.
FINDINGS
We included a total of 179 cases, 162 of which belong to 25 families. Availability of information ranged from 96.6% for ethnicity to 24.4% for AAO. All cases had calcifications on comprehensive cranial computed tomography, most frequently located in the basal ganglia (70.6%), subcortical white matter (40.8%), cerebellum (34.1%), or thalamus (28.5%). Mean (SD) AAO was 27.9 (22.3) years, and the AAO was comparable across genes (P=.77). The most frequently described signs were movement disorders, such as parkinsonism (12%) and dystonia (19%). Penetrance of the imaging phenotype was 100% compared with only 61% of the clinical phenotype. We propose a novel definition of disease status by specifying PFBC into genetic, clinical, and imaging phenotypes. Pathophysiological pathways converge on impaired phosphorus homeostasis and integrity of the blood-brain barrier.
CONCLUSIONS AND RELEVANCE
Especially in rare conditions, meta-analyses are the most suitable tool to extract reliable information on the natural course of a disease. For future analyses, we provide a minimal data set that can be used for systematic clinical and imaging data collection in PFBC and that will also improve informed counseling of patients.
Topics: Age of Onset; Brain Diseases; Calcinosis; Humans; Movement Disorders; Mutation; Phenotype
PubMed: 25686319
DOI: 10.1001/jamaneurol.2014.3889