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Circulation. Genomic and Precision... Oct 2021The p.Val142Ile variant, predominantly found among people of African descent, is the most common cause of variant transthyretin amyloidosis and carriers predominantly...
BACKGROUND
The p.Val142Ile variant, predominantly found among people of African descent, is the most common cause of variant transthyretin amyloidosis and carriers predominantly develop a cardiomyopathy (variant transthyretin amyloidosis cardiomyopathy) phenotype. Yet, there are conflicting data on the prevalence and outcomes of p.Val142Ile variant carriers.
METHODS
We performed a systematic review of the prevalence and outcomes of p.Val142Ile variant transthyretin amyloidosis cardiomyopathy among subjects of African descent. We found 62 relevant articles after searching the MEDLINE databases from 1980 to 2020 that reported data for ≈150 000 subjects.
RESULTS
The reported worldwide prevalence of the p.Val142Ile variant is 0.3% to 1.6% in the general population. Among people of African descent, the reported prevalence from all studies ranges from 1.1% to 9.8%, but for studies with >1000 subjects, it is 3% to 3.5%. The prevalence of the p.Val142Ile variant in a region is dependent on the reported percentage of subjects who are of African descent in that region. p.Val142Ile variant transthyretin amyloidosis cardiomyopathy typically presents in the seventh to eighth decade of life and the majority of cases reported were male, with 25% to 38% diagnosed with atrial fibrillation. It was associated with a longitudinally worse quality of life and a lower adjusted survival compared with other types of transthyretin amyloidosis cardiomyopathy.
CONCLUSIONS
The p.Val142Ile variant is the most common variant of the transthyretin gene with most carriers being of African descent. The true penetrance is unknown but the p.Val142Ile variant is associated with increased rates of incident heart failure and portends a lower overall survival. Increased awareness could lead to earlier diagnosis and improved heart failure outcomes among those of African descent, which is of increasing importance given the advent of novel therapeutics for this disease.
Topics: Amino Acid Substitution; Amyloid Neuropathies, Familial; Cardiomyopathies; Female; Humans; Male; Mutation, Missense; Prealbumin; Prevalence; Risk Factors; Sex Factors
PubMed: 34461737
DOI: 10.1161/CIRCGEN.121.003356 -
The American Journal of Clinical... Aug 2013Hereditary hemochromatosis (HH) leads to iron loading because of a disturbance in the negative-feedback mechanism between dietary iron absorption and iron status. The... (Review)
Review
BACKGROUND
Hereditary hemochromatosis (HH) leads to iron loading because of a disturbance in the negative-feedback mechanism between dietary iron absorption and iron status. The management of HH is achieved by repeated phlebotomies.
OBJECTIVE
We investigated whether HH patients would benefit from a diet with low iron intake and bioavailability.
DESIGN
We performed a systematic review of studies that linked iron bioavailability and status with dietary factors in subjects with diagnosed HH. Studies on heterozygotes for the HFE mutation were excluded.
RESULTS
No prospective, randomized study was reported. Nine studies that directly measured iron bioavailability from test meals in HH patients have been described as well as 3 small, prospective, longitudinal studies in HH patients. Eight cross-sectional studies were identified that investigated the effect of dietary composition on iron status. Calculations of iron bioavailability in HH were made by extrapolating data on hepcidin concentrations and their association with iron bioavailability. The potential reduction in the yearly amount of blood to be phlebotomized when restricting dietary iron absorbed was estimated in the 3 longitudinal studies and ranged between 0.5 and 1.5 L. This amount would be dependent on individual disease penetrance as well as the dietary intervention.
CONCLUSIONS
Despite the limited quantitative evidence and the lack of randomized, prospective trials, dietary interventions that modify iron intake and bioavailability may affect iron accumulation in HH patients. Although this measure may be welcome in patients willing to contribute to their disease management, limited data exist on the clinical and quality-of-life benefit.
Topics: Absorption; Antimicrobial Cationic Peptides; Biological Availability; Diet; Hemochromatosis; Hepcidins; Heterozygote; Humans; Iron, Dietary; Mutation; Penetrance
PubMed: 23803887
DOI: 10.3945/ajcn.112.048264 -
Ultrasound in Obstetrics & Gynecology :... Apr 2018To establish, based on a systematic literature review, the frequency of pathogenic submicroscopic chromosomal aberrations in fetuses that are not at increased risk for... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To establish, based on a systematic literature review, the frequency of pathogenic submicroscopic chromosomal aberrations in fetuses that are not at increased risk for unbalanced structural chromosomal aberrations, with the aim of determining whether high-resolution testing for submicroscopic aberrations is beneficial in a general pregnant population.
METHODS
EMBASE, PubMed, Web of Science and CENTRAL databases were searched systematically on 3 June 2016 for all relevant articles on the prevalence of pathogenic submicroscopic copy number variants (CNVs) in fetuses referred for prenatal invasive testing because of advanced maternal age (AMA) or parental anxiety (ANX). Relevant full-text articles were analyzed and the prevalence of submicroscopic CNVs was calculated based on the extracted data. Meta-analysis was conducted in a pooled cohort of 10 614 fetuses based on the 10 largest studies (n > 300) of a total of 19 that were relevant.
RESULTS
Pooled estimate analysis indicated that 0.84% (95% CI, 0.55-1.30%) of fetuses that had invasive testing because of AMA/ANX carried a pathogenic clinically significant submicroscopic aberration. The onset/penetrance of submicroscopic findings was studied in 10 314 fetuses reported in eight papers that presented aberrant cases with all necessary details to allow assessment of the findings. The pooled estimates resulting from meta-analysis of the data indicated that an early-onset syndromic disorder was detected in 0.37% (95% CI, 0.27-0.52%) of cases, a susceptibility CNV was found in 0.30% (95% CI, 0.14-0.67%) and late-onset diseases were reported in 0.11% (95% CI, 0.05%-0.21%). The prevalence of early-onset syndromic disorders caused by a submicroscopic aberration was calculated to be 1:270. When the risk for submicroscopic aberrations is added to the individual risk for microscopic chromosomal aberrations, all pregnant women have a risk of higher than 1 in 180 for a relevant chromosomal aberration, and pregnant women under 36 years of age have a higher risk for submicroscopic pathogenic aberrations than for Down syndrome.
CONCLUSION
This systematic review shows that a significant proportion of fetuses in a general pregnant population carry a submicroscopic pathogenic CNV. Based on these figures, all women should be informed on their individual risk for all pathogenic chromosomal aberrations and not only for common trisomies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Chromosome Aberrations; Cohort Studies; DNA Copy Number Variations; Down Syndrome; Female; Humans; Maternal Age; Oligonucleotide Array Sequence Analysis; Pregnancy; Risk; Ultrasonography, Prenatal
PubMed: 28556491
DOI: 10.1002/uog.17533 -
Journal of Hepatology Nov 2010Classical ferroportin disease is characterized by hyperferritinemia, normal transferrin saturation, and iron overload in macrophages. A non-classical form is... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Classical ferroportin disease is characterized by hyperferritinemia, normal transferrin saturation, and iron overload in macrophages. A non-classical form is characterized by additional hepatocellular iron deposits and a high transferrin saturation. Both forms demonstrate autosomal dominant transmission and are associated with ferroportin gene (SLC40A1) mutations. SLC40A1 encodes a cellular iron exporter expressed in macrophages, enterocytes, and hepatocytes. The aim of the analysis is to determine the penetrance of SLC40A1 mutations and to evaluate in silico tools to predict the functional impairment of ferroportin mutations as an alternative to in vitro studies.
METHODS
We conducted a systematic review of the literature and meta-analysis of the biochemical presentation, genetics, and pathology of ferroportin disease.
RESULTS
Of the 176 individuals reported with SLC40A1 mutations, 80 were classified as classical phenotype with hyperferritinemia and normal transferrin saturation. The non-classical phenotype with hyperferritinemia and elevated transferrin saturation was present in 53 patients. The remaining patients had normal serum ferritin or the data were reported incompletely. Despite an increased hepatic iron concentration in all biopsied patients, significant fibrosis or cirrhosis was present in only 11%. Hyperferritinemia was present in 86% of individuals with ferroportin mutations. Bio-informatic analysis of ferroportin mutations showed that the PolyPhen score has a sensitivity of 99% and a specificity of 67% for the discrimination between ferroportin mutations and polymorphisms.
CONCLUSIONS
In contrast to HFE hemochromatosis, ferroportin disease has a high penetrance, is genetically heterogeneous and is rarely associated with fibrosis. Non-classical ferroportin disease is associated with a higher risk of fibrosis and a more severe overload of hepatic iron.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Amino Acid Sequence; Cation Transport Proteins; Child; Child, Preschool; Female; Ferritins; Hemochromatosis; Humans; Iron Overload; Male; Middle Aged; Molecular Sequence Data; Mutation; Polymorphism, Genetic; Transferrin
PubMed: 20691492
DOI: 10.1016/j.jhep.2010.05.016 -
Clinical Kidney Journal Jan 2024Several studies have examined the frequency of sleep apnoea (SA) in patients with chronic kidney disease (CKD), reporting different prevalence rates. Our systematic...
BACKGROUND
Several studies have examined the frequency of sleep apnoea (SA) in patients with chronic kidney disease (CKD), reporting different prevalence rates. Our systematic review and meta-analysis aimed to define the clinical penetrance of SA in CKD and end-stage kidney disease (ESKD) patients.
METHODS
Ovid-MEDLINE and PubMed databases were explored up to 5 June 2023 to identify studies providing SA prevalence in CKD and ESKD patients assessed by different diagnostic methods, either sleep questionnaires or respiration monitoring equipment [such as polysomnography (PSG), type III portable monitors or other diagnostic tools]. Single-study data were pooled using the random-effects model. The Chi and Cochrane-I tests were used to assess the presence of heterogeneity, which was explored performing sensitivity and/or subgroup analyses.
RESULTS
A cumulative analysis from 32 single-study data revealed a prevalence of SA of 57% [95% confidence interval (CI) 42%-71%] in the CKD population, whereas a prevalence of 49% (95% CI 47%-52%) was found pooling data from 91 studies in ESKD individuals. The prevalence of SA using instrumental sleep monitoring devices, including classical PSG and type III portable sleep monitors, was 62% (95% CI 52%-72%) and 56% (95% CI 42%-69%) in CKD and ESKD populations, respectively. Sleep questionnaires revealed a prevalence of 33% (95% CI 16%-49%) and 39% (95% CI 30%-49%).
CONCLUSIONS
SA is commonly seen in both non-dialysis CKD and ESKD patients. Sleep-related questionnaires underestimated the presence of SA in this population. This emphasizes the need to use objective diagnostic tools to identify such a syndrome in kidney disease.
PubMed: 38186876
DOI: 10.1093/ckj/sfad179 -
Journal of Medical Genetics Nov 2023While constitutional pathogenic variants in the gene cause familial adenomatous polyposis, c.3920T>A; p.Ile1307Lys (I1307K) has been associated with a moderate... (Meta-Analysis)
Meta-Analysis
While constitutional pathogenic variants in the gene cause familial adenomatous polyposis, c.3920T>A; p.Ile1307Lys (I1307K) has been associated with a moderate increased risk of colorectal cancer (CRC), particularly in individuals of Ashkenazi Jewish descent. However, published data include relatively small sample sizes, generating inconclusive results regarding cancer risk, particularly in non-Ashkenazi populations. This has led to different country/continental-specific guidelines regarding genetic testing, clinical management and surveillance recommendations for I1307K. A multidisciplinary international expert group endorsed by the International Society for Gastrointestinal Hereditary Tumours (InSiGHT), has generated a position statement on the I1307K allele and its association with cancer predisposition. Based on a systematic review and meta-analysis of the evidence published, the aim of this document is to summarise the prevalence of the I1307K allele and analysed the evidence of the associated cancer risk in different populations. Here we provide recommendations on the laboratory classification of the variant, define the role of predictive testing for I1307K, suggest recommendations for cancer screening in I1307K heterozygous and homozygous individuals and identify knowledge gaps to be addressed in future research studies. Briefly, I1307K, classified as pathogenic, low penetrance, is a risk factor for CRC in individuals of Ashkenazi Jewish origin and should be tested in this population, offering carriers specific clinical surveillance. There is not enough evidence to support an increased risk of cancer in other populations/subpopulations. Therefore, until/unless future evidence indicates otherwise, individuals of non-Ashkenazi Jewish descent harbouring I1307K should be enrolled in national CRC screening programmes for average-risk individuals.
Topics: Humans; Genetic Predisposition to Disease; Adenomatous Polyposis Coli; Colorectal Neoplasms; Genes, APC; Risk Factors; Jews
PubMed: 37076288
DOI: 10.1136/jmg-2022-108984 -
PloS One 2012Cyclin D1 (CCND1) plays a vital role in cancer cell cycle progression. Numerous epidemiological studies have evaluated the association between the CCND1 G870A... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cyclin D1 (CCND1) plays a vital role in cancer cell cycle progression. Numerous epidemiological studies have evaluated the association between the CCND1 G870A polymorphism and the risk of colorectal cancer. However, these studies have yielded conflicting results. To derive a more precise estimation of this association, we conducted a meta-analysis and systematic review.
METHODOLOGY/PRINCIPAL FINDINGS
A comprehensive search was conducted to identify eligible studies of the CCND1 G870A polymorphism and colorectal cancer risk. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were derived from a fixed effect or random effect model. We applied a grading system (Venice criteria) that assessed the epidemiological strength of the association. A total of 22 publications that included 6157 cases and 8198 controls were identified. We found that the CCND1 G870A polymorphism was significantly associated with overall colorectal cancer risk (homozygote genetic model: OR = 1.130, 95% CI = 1.023-1.248, P = 0.016; heterozygote genetic model: OR = 1.124, 95% CI = 1.030-1.226, P = 0.009; dominant genetic model: OR = 1.127, 95% CI = 1.037-1.224, P = 0.005). After further stratified analyses, the increased risk was observed only in the subgroups of hospital-based studies, PCR-RFLP genotyping methods, sporadic colorectal cancer, and Caucasian ethnicity.
CONCLUSIONS
The available evidence demonstrates that the CCND1 870A allele might be a low-penetrant risk factor for colorectal cancer.
Topics: Case-Control Studies; Colorectal Neoplasms; Cyclin D1; Female; Genes, bcl-1; Genetic Predisposition to Disease; Humans; Male; Polymorphism, Single Nucleotide; Risk Factors; White People
PubMed: 22606291
DOI: 10.1371/journal.pone.0036813 -
International Journal of Molecular... Feb 2024Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder characterized by the progressive fibro-fatty replacement of the right ventricular... (Review)
Review
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder characterized by the progressive fibro-fatty replacement of the right ventricular myocardium, leading to myocardial atrophy. Although the structural changes usually affect the right ventricle, the pathology may also manifest with either isolated left ventricular myocardium or biventricular involvement. As ARVC shows an autosomal dominant pattern of inheritance with variable penetrance, the clinical presentation of the disease is highly heterogeneous, with different degrees of severity and patterns of myocardial involvement even in patients of the same familiar group with the same gene mutation: the pathology spectrum ranges from the absence of symptoms to sudden cardiac death (SCD) sustained by ventricular arrhythmias, which may, in some cases, be the first manifestation of an otherwise silent pathology. An evidence-based systematic review of the literature was conducted to evaluate the state of the art of the diagnostic techniques for the correct post-mortem identification of ARVC. The research was performed using the electronic databases PubMed and Scopus. A methodological approach to reach a correct post-mortem diagnosis of ARVC was described, analyzing the main post-mortem peculiar macroscopic, microscopic and radiological alterations. In addition, the importance of performing post-mortem genetic tests has been underlined, which may lead to the correct identification and characterization of the disease, especially in those ARVC forms where anatomopathological investigation does not show evident morphostructural damage. Furthermore, the usefulness of genetic testing is not exclusively limited to the correct diagnosis of the pathology, but is essential for promoting targeted screening programs to the deceased's family members. Nowadays, the post-mortem diagnosis of ARVC performed by forensic pathologist remains very challenging: therefore, the identification of a clear methodological approach may lead to both a reduction in under-diagnoses and to the improvement of knowledge on the disease.
Topics: Humans; Arrhythmogenic Right Ventricular Dysplasia; Autopsy; Myocardium; Databases, Factual; Death, Sudden, Cardiac
PubMed: 38473714
DOI: 10.3390/ijms25052467 -
Genetics in Medicine : Official Journal... May 2011Autism is one of the most heritable complex disorders, but the genetic etiology of autism spectrum disorders is unexplained in ∼ 90% of cases. Highly penetrant... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Autism is one of the most heritable complex disorders, but the genetic etiology of autism spectrum disorders is unexplained in ∼ 90% of cases. Highly penetrant microdeletions and microduplications of 16p11.2 contribute to the pathogenesis of autism spectrum disorder, but the extent to which these variants account for the total burden of idiopathic autism spectrum disorders has not been systematically investigated.
METHODS
A systematic literature review and meta-analysis were performed to determine the prevalence of these variants among individuals diagnosed with autism spectrum disorders. A planned subgroup analysis was conducted to assess prevalence differences between sporadic and familial autism spectrum disorder cases.
RESULTS
In the combined analysis of 3613 idiopathic autism spectrum disorder cases from seven studies, the meta-analytic prevalence of these microdeletions and microduplications was 0.76% (95% CI, 0.51-1.12%). When stratified by copy number variant-type, the prevalence of microdeletions was 0.50% (95% CI, 0.31-0.82%) and the prevalence of microduplications was 0.28% (95% CI, 0.14-0.56%). Sporadic autism spectrum disorder cases showed only a slightly higher prevalence than familial cases.
CONCLUSION
The number needed to test to identify one such variant is 132 patients (95% CI, 89-198). Such information, especially as it pertains to diagnostic yield in genetic testing, should prove useful to clinicians considering chromosomal microarray analysis in subjects with autism spectrum disorders.
Topics: Child; Child Development Disorders, Pervasive; Chromosome Deletion; Chromosome Duplication; Chromosomes, Human, Pair 16; DNA Copy Number Variations; Gene Dosage; Humans; Incidence; Publication Bias
PubMed: 21289514
DOI: 10.1097/GIM.0b013e3182076c0c -
Cancers Mar 2024Neurofibromatosis Type 1 is an autosomal dominant tumour-predisposition condition commonly diagnosed in childhood and fully penetrant by adulthood. Long-term monitoring... (Review)
Review
BACKGROUND
Neurofibromatosis Type 1 is an autosomal dominant tumour-predisposition condition commonly diagnosed in childhood and fully penetrant by adulthood. Long-term monitoring through imaging is inconsistent and varies between high- and low-income countries. Implementation of a clinical practice guideline through a multidisciplinary clinic is instrumental to the care of adult Neurofibromatosis Type 1 patients. We aim to systematically review international diagnostic modalities and strategies to evaluate any association between a country's socioeconomic status and diagnostic modalities or strategies used for Neurofibromatosis Type 1 patients.
METHODS
We searched PubMed, Embase, Web of Science, and Cochrane. Relevant clinical information on the surveillance of adult Neurofibromatosis Type 1 patients worldwide was reviewed, extracted, and synthesised.
RESULTS
We identified 51 papers reporting on 7724 individuals. Multiple imaging modalities are actively employed in high-income and upper-middle-income countries for surveying adult Neurofibromatosis Type 1 patients. We did not find any relevant papers from low- and middle-income countries.
CONCLUSIONS
This systematic review suggests that there is robust data on diagnostic modalities for adult Neurofibromatosis Type 1 patients in high-income countries, but not for low- and middle-income countries. There is a lack of data on consolidated diagnostic strategies from both high- and low-income countries. Efforts should be made to publish data on usual clinical practice in low- and middle-income countries to develop clinical practice guidelines describing best medical practice to fit a local context.
PubMed: 38539455
DOI: 10.3390/cancers16061119