scholarly journals The global carrier frequency and genetic prevalence of Upshaw-Schulman syndrome

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ting Zhao ◽  
Shanghua Fan ◽  
Liu Sun
Keyword(s):  
Allele Frequency ◽  
Carrier Frequency ◽  
Autosomal Recessive ◽  
Autosomal Recessive Disease ◽  
Medical Genetics ◽  
Allele Frequencies ◽  
The Novel ◽  
Thrombotic Microangiopathies ◽  
Pathogenic Variants ◽  
Genetics And Genomics

Abstract Background Upshaw–Schulman syndrome (USS) is an autosomal recessive disease characterized by thrombotic microangiopathies caused by pathogenic variants in ADAMTS13. We aimed to (1) curate the ADAMTS13 gene pathogenic variant dataset and (2) estimate the carrier frequency and genetic prevalence of USS using Genome Aggregation Database (gnomAD) data. Methods Studies were comprehensively retrieved. All previously reported pathogenic ADAMTS13 variants were compiled and annotated with gnomAD allele frequencies. The pooled global and population-specific carrier frequencies and genetic prevalence of USS were calculated using the Hardy-Weinberg equation. Results We mined reported disease-causing variants that were present in the gnomAD v2.1.1, filtered by allele frequency. The pathogenicity of variants was classified according to the American College of Medical Genetics and Genomics criteria. The genetic prevalence and carrier frequency of USS were 0.43 per 1 million (95% CI: [0.36, 0.55]) and 1.31 per 1 thousand population, respectively. When the novel pathogenic/likely pathogenic variants were included, the genetic prevalence and carrier frequency were 1.1 per 1 million (95% CI: [0.89, 1.37]) and 2.1 per 1 thousand population, respectively. Conclusions The genetic prevalence and carrier frequency of USS were within the ranges of previous estimates.

scholarly journals The global carrier frequency and genetic prevalence of Upshaw-Schulman syndrome

2021 ◽  
Author(s):  
Ting Zhao ◽  
Shanghua Fan ◽  
Liu Sun
Keyword(s):  
Data Mining ◽  
Allele Frequency ◽  
Thrombotic Microangiopathy ◽  
Carrier Frequency ◽  
Autosomal Recessive ◽  
Autosomal Recessive Disease ◽  
Medical Genetics ◽  
Allele Frequencies ◽  
Pathogenic Variants ◽  
Genetics And Genomics

Purpose: Upshaw-Schulman syndrome (USS) is an autosomal recessive disease of thrombotic microangiopathy, caused by pathogenic variants in ADAMTS13. We aimed to (1) perform data mining pathogenicity of ADAMTS13 variants, (2) estimate carrier frequency and genetic prevalence of USS from gnomAD data, and (3) curated ADAMTS13 gene pathogenic variants database. Methods: PubMed and Scopus were comprehensive retrieved. All previously reported pathogenic ADAMTS13 variants were compiled and annotated with gnomAD allele frequencies. Pooled global and population-specific carrier frequency and genetic prevalence for USS were calculated using Hardy-Weinberg equation. Results: we mined reported disease-causing variants, of these were present in gnomAD exomes v2.1.1, filtering by allele frequency, pathogenicity of variants were classified by American College of Medical Genetics and Genomics criteria. The genetic prevalence and carrier frequency of USS was 0.43 per 1 million (95% CI: [0.36, 0.55]) and 1.31 per thousand, respectively. Combining known with novel pathogenic/likely pathogenic variants, the genetic prevalence and carrier frequency are 1 per 1 million (95% CI: [0.89, 1.37]) and 2.1 per thousand, respectively. Conclusion: the genetic prevalence and carrier frequency of Upshaw-Schulman syndrome are within range of previously rough estimated.

scholarly journals Diagnostic exome-based preconception carrier testing in consanguineous couples: results from the first 100 couples in clinical practice

2021 ◽  
Author(s):  
Suzanne C. E. H. Sallevelt ◽  
Alexander P. A. Stegmann ◽  
Bart de Koning ◽  
Crool Velter ◽  
Anja Steyls ◽  
...  
Keyword(s):  
Autosomal Recessive ◽  
Rare Variants ◽  
Clinical Care ◽  
Carrier Testing ◽  
Carrier Status ◽  
Routine Diagnostics ◽  
Affected Offspring ◽  
Pathogenic Variants ◽  
Increased Risk ◽  
Genetics And Genomics

Abstract Purpose Consanguineous couples are at increased risk of being heterozygous for the same autosomal recessive (AR) disorder(s), with a 25% risk of affected offspring as a consequence. Until recently, comprehensive preconception carrier testing (PCT) for AR disorders was unavailable in routine diagnostics. Here we developed and implemented such a test in routine clinical care. Methods We performed exome sequencing (ES) for 100 consanguineous couples. For each couple, rare variants that could give rise to biallelic variants in offspring were selected. These variants were subsequently filtered against a gene panel consisting of ~2,000 genes associated with known AR disorders (OMIM-based). Remaining variants were classified according to American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) guidelines, after which only likely pathogenic and pathogenic (class IV/V) variants, present in both partners, were reported. Results In 28 of 100 tested consanguineous couples (28%), likely pathogenic and pathogenic variants not previously known in the couple or their family were reported conferring 25% risk of affected offspring. Conclusion ES-based PCT provides a powerful diagnostic tool to identify AR disease carrier status in consanguineous couples. Outcomes provided significant reproductive choices for a higher proportion of these couples than previous tests.

scholarly journals Combination of Novel c.3484G> T/p.Glu162Ter Variant in ABCB11 and c.208G> A/p.Asp70Asn Variant in ATP8B1 Are Associated with Severe Symptoms in Progressive Family Intrahepatic Cholestasis

2020 ◽  
Vol 09 (04) ◽  
pp. 285-288
Author(s):  
Mervan Bekdas ◽  
Guray Can ◽  
Recep Eroz ◽  
Selma Erdogan Duzcu
Keyword(s):  
Intrahepatic Cholestasis ◽  
Autosomal Recessive ◽  
Autosomal Recessive Disease ◽  
Bile Secretion ◽  
Peripheral Blood Sample ◽  
Portal Fibrosis ◽  
Traditional Treatment ◽  
Pathogenic Variants ◽  
Chronic Cholestasis ◽  
Whole Exome

AbstractProgressive family intrahepatic cholestasis (PFIC) is an autosomal recessive disease that causes chronic cholestasis. It is associated with pathogenic variants in genes that encode proteins involved in bile secretion to canaliculus from hepatocytes. In this study, we present a 16-year-old boy who presented with severe pruritus and cholestatic jaundice. All possible infectious etiologies were negative. A liver biopsy was consistent with intrahepatic cholestasis and portal fibrosis. DNA was isolated from a peripheral blood sample, and whole exome sequencing was performed. A novel c.3484G > T/p.Glu162Ter variant in the ABCB11 gene and a c.208G> A/p.Asp70Asn variant in the ATP8B1 gene were detected. Despite traditional treatment, the patient's recurrent severe symptoms did not improve. The patient was referred for a liver transplantation. This novel c.3484G > T/p.Glu162Ter variant is associated with a severe and recurrent presentation, and the two compound variants could explain the severity of PFIC.

scholarly journals Examination of the predicted prevalence of Gitelman syndrome by ethnicity based on genome databases

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Atsushi Kondo ◽  
China Nagano ◽  
Shinya Ishiko ◽  
Takashi Omori ◽  
Yuya Aoto ◽  
...  
Keyword(s):  
Allele Frequency ◽  
Carrier Frequency ◽  
Japanese Population ◽  
Autosomal Recessive ◽  
Disease Prevalence ◽  
Gitelman Syndrome ◽  
Variant Allele ◽  
Variant Allele Frequency ◽  
Genome Databases ◽  
Heterozygous Carriers

AbstractGitelman syndrome is an autosomal recessive inherited salt-losing tubulopathy. It has a prevalence of around 1 in 40,000 people, and heterozygous carriers are estimated at approximately 1%, although the exact prevalence is unknown. We estimated the predicted prevalence of Gitelman syndrome based on multiple genome databases, HGVD and jMorp for the Japanese population and gnomAD for other ethnicities, and included all 274 pathogenic missense or nonsense variants registered in HGMD Professional. The frequencies of all these alleles were summed to calculate the total variant allele frequency in SLC12A3. The carrier frequency and the disease prevalence were assumed to be twice and the square of the total allele frequency, respectively, according to the Hardy–Weinberg principle. In the Japanese population, the total carrier frequencies were 0.0948 (9.5%) and 0.0868 (8.7%) and the calculated prevalence was 0.00225 (2.3 in 1000 people) and 0.00188 (1.9 in 1000 people) in HGVD and jMorp, respectively. Other ethnicities showed a prevalence varying from 0.000012 to 0.00083. These findings indicate that the prevalence of Gitelman syndrome in the Japanese population is higher than expected and that some other ethnicities also have a higher prevalence than has previously been considered.

scholarly journals Exact Distribution of Linkage Disequilibrium in the Presence of Mutation, Selection or Minor Allele Frequency Filtering

2019 ◽  
Author(s):  
Jiayi Qu ◽  
Stephen D Kachman ◽  
Dorian Garrick ◽  
Rohan L Fernando ◽  
Hao Cheng
Keyword(s):  
Linkage Disequilibrium ◽  
Allele Frequency ◽  
Minor Allele Frequency ◽  
Finite Population ◽  
Exact Distribution ◽  
Minor Allele ◽  
Allele Frequencies ◽  
Frequency Filtering ◽  
Genetics And Genomics ◽  
Deterministic Formula

ABSTRACTLinkage disequilibrium (LD), often expressed in terms of the squared correlation (r2) between allelic values at two loci, is an important concept in many branches of genetics and genomics. Genetic drift and recombination have opposite effects on LD, and thus r2 will keep changing until the effects of these two forces are counterbalanced. Several approximations have been used to determine the expected value of r2 at equilibrium in the presence or absence of mutation. In this paper, we propose a probability-based approach to compute the exact distribution of allele frequencies at two loci in a finite population at any generation t conditional on the distribution at generation t − 1. As r2 is a function of this distribution of allele frequencies, this approach can be used to examine the distribution of r2 over generations as it approaches equilibrium. The exact distribution of LD from our method is used to describe, quantify and compare LD at different equilibria, including equilibrium in the absence or presence of mutation, selection, and filtering by minor allele frequency. We also propose a deterministic formula for expected LD in the presence of mutation at equilibrium based on the exact distribution of LD.

Exome Sequencing Highlights a Potential Role for Concealed Cardiomyopathies in Youthful Sudden Cardiac Death

2021 ◽  
Author(s):  
Raquel Neves ◽  
David J. Tester ◽  
Michael A. Simpson ◽  
Elijah R. Behr ◽  
Michael J. Ackerman ◽  
...  
Keyword(s):  
Exome Sequencing ◽  
Strong Evidence ◽  
Susceptibility Gene ◽  
Susceptibility Genes ◽  
Medical Genetics ◽  
Variant Of Uncertain Significance ◽  
Pathogenic Variants ◽  
Genetic Test Results ◽  
Uncertain Significance ◽  
Genetics And Genomics

Background: Sudden cardiac arrest (SCA) and sudden unexplained death (SUD) are feared sequelae of many genetic heart diseases. In rare circumstances, pathogenic variants in cardiomyopathy-susceptibility genes may result in electrical instability leading to SCA/SUD before any structural manifestations of underlying cardiomyopathy are evident. Methods: Collectively, 38 unexplained SCA survivors (21 males; mean age at SCA 26.4±13.1 years), 68 autopsy-inconclusive SUD cases (49 males; mean age at death 20.4±9.0 years) without disease-causative variants in the channelopathy genes, and 973 ostensibly healthy controls were included. Following exome sequencing, ultrarare (minor allele frequency ≤0.00005 in any ethnic group within Genome Aggregation Database [gnomAD, n=141 456 individuals]) nonsynonymous variants identified in 24 ClinGen adjudicated definitive/strong evidence cardiomyopathy-susceptibility genes were analyzed. Eligible variants were adjudicated as pathogenic, likely pathogenic, or variant of uncertain significance in accordance with current American College of Medical Genetics and Genomics guidelines. Results: Overall, 7 out of 38 (18.4%) SCA survivors and 14 out of 68 (20.5%) autopsy-inconclusive, channelopathic-negative SUD cases had at least one pathogenic/likely pathogenic or a variant of uncertain significance nonsynonymous variant within a strong evidence, cardiomyopathy-susceptibility gene. Following American College of Medical Genetics and Genomics criterion variant adjudication, a pathogenic or likely pathogenic variant was identified in 3 out of 38 (7.9%; P =0.05) SCA survivors and 8 out of 68 (11.8%; P =0.0002) autopsy-inconclusive SUD cases compared to 20 out of 973 (2.1%) European controls. Interestingly, the yield of pathogenic/likely pathogenic variants was significantly greater in autopsy-inconclusive SUD cases with documented interstitial fibrosis (4/11, 36%) compared with only 4 out of 57 (7%, P <0.02) SUD cases without ventricular fibrosis. Conclusion: Our data further supports the inclusion of strongevidence cardiomyopathy-susceptibility genes on the genetic testing panels used to evaluate unexplained SCA survivors and autopsy-inconclusive/negative SUD decedents. However, to avoid diagnostic miscues, the careful interpretation of genetic test results in patients without overt phenotypes is vital.

scholarly journals Estimating lethal allele frequencies in complex pedigrees via gene dropping approach using the example of Brown Swiss cattle

2009 ◽  
Vol 52 (3) ◽  
pp. 230-242 ◽  
Author(s):  
S. Manatrinon ◽  
C. Egger-Danner ◽  
R. Baumung
Keyword(s):  
Allele Frequency ◽  
Autosomal Recessive ◽  
Muscular Atrophy ◽  
Genetic Disorders ◽  
Allele Frequencies ◽  
Pedigree Information ◽  
Brown Swiss ◽  
Breeding Populations ◽  
Lethal Allele ◽  
Gene Origin

Abstract. A new approach to estimating the allele frequencies of lethal autosomal-recessive genetic disorders was developed based on the gene dropping method. The method was tested in the complex pedigrees of 1 830 125 animals of the Austrian Brown Swiss population, where carriers for 4 genetic disorders were recorded. Trends of allele frequencies of Spinal Dysmyelination and Spinal Muscular Atrophy increased while Weaver decreased, but allele frequencies of Arachnomelia fluctuated between 2 and 3 %. The results were compared to the results from other methods. The results obtained from probability of gene origin were higher than the results from gene dropping in general, while the results from gene counting were lowest due to the fact that just a part of the pedigree information could be considered by the used program. The gene dropping and gene counting methods used here take lethal selection into account, while the program based on probability of gene origin does not. Therefore, gene dropping and gene counting seem to be more appropriate for estimating the lethal allele frequency of lethal autosomal-recessive genetic disorders. Applying the gene dropping approach, one can obtain the distribution of allele frequencies and confidence intervals for the allele frequency, which might be valuable for observing trends in active breeding populations.

scholarly journals Expanding the Russian allele frequency reference via cross-laboratory data integration: insights from 6,096 exome samples

2021 ◽  
Author(s):  
Yury A Barbitoff ◽  
Darya N Khmelkova ◽  
Ekaterina A Pomerantseva ◽  
Aleksandr V Slepchenkov ◽  
Nikita A Zubashenko ◽  
...  
Keyword(s):  
Allele Frequency ◽  
Genetic Variant ◽  
Laboratory Data ◽  
Medical Genetics ◽  
Pathogenic Variants ◽  
Healthy Donors ◽  
Tenfold Increase ◽  
Novel Variant ◽  
Specific Allele ◽  
Admixed Population

The frequency of a genetic variant in a population is crucially important for accurate interpretation of known and novel variant effects in medical genetics. Recently, several large allele frequency databases, such as Genome Aggregation Database (gnomAD), have been created to serve as a global reference for such studies. However, frequencies of many rare alleles vary dramatically between populations, and population-specific allele frequency can be more informative than the global one. Many countries and regions (including Russia) remain poorly studied from the genetic perspective. Here, we report the first successful attempt to integrate genetic information between major medical genetic laboratories in Russia. We construct an expanded reference set of genetic variants by analyzing 6,096 exome samples collected in two major Russian cities of Moscow and St. Petersburg. An approximately tenfold increase in sample size compared to previous studies allowed us to identify genetically distinct clusters of individuals within an admixed population of Russia. We show that up to 18 known pathogenic variants are overrepresented in Russia compared to other European countries. We also identify several dozen high-impact variants that are present in healthy donors despite either being annotated as pathogenic in ClinVar or falling within genes associated with autosomal dominant disorders. The constructed database of genetic variant frequencies in Russia has been made available to the medical genetics community through a variant browser available at http://ruseq.ru.

Sign in / Sign up

Export Citation Format

Share Document