The Added Value of Whole-Exome Sequencing for Anomalous Fetuses With Detailed Prenatal Ultrasound and Postnatal Phenotype

ObjectivesThe objective of the study was to explore the added value of whole-exome sequencing (WES) in abnormal fetuses with detailed prenatal ultrasound and postnatal phenotype with normal karyotype and chromosomal microarray analysis (CMA).MethodsParents of fetuses with structural abnormalities by prenatal ultrasound who consented to provide fetal samples were prospectively recruited from January 2017 to December 2019. With aneuploidies or cases with copy number variations (CNVs) excluded, WES was performed for cases with normal karyotype and CMA results. Detailed prenatal ultrasound and postnatal imaging or pathology features were recommended for further interpretation of genetic variants.ResultsWES was performed for 94 eligible fetuses, DNA samples of which were extracted from 53 parent–fetus trios and 41 proband-only fetal tissues. A diagnostic genetic variant was identified in 37 (39.4%) of 94 fetuses, and 34 (64.2%) were detected in 53 trios, which was significantly greater than 3 (7.3%) in 41 proband-only cases (p < 0.001). In 34 trios with diagnostic genetic variants, 23 (67.6%) were de novo and 11 (32.4%) were inherited with two homozygous and nine heterozygous variants. Fourteen (14.9%) of 94 fetuses had a variant of uncertain significance (VUS). Among 94 cases, six affected pregnancies continued and 88 terminated, and 57 of 88 terminated cases underwent postmortem examinations. With accurate phenotypes demonstrated by prenatal ultrasound and postnatal autopsies, the clinical phenotypes were correlated in 33 (89.2%) of 37 cases with specific genotypes, with the highest matching ratio in skeletal diseases (20/33, 60.6%).ConclusionWES has added value in the genetic diagnosis of abnormal fetuses with normal karyotypes and CMA, particularly in skeletal diseases. Using WES in various anomalous fetuses can broaden the understanding of prenatal phenotypes and genetic variants.

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Whole‐Exome Sequencing and Chromosomal Microarray Analysis Feasible and Cost‐Effective in an Underserved Population: Whole‐exome sequencing and chromosomal microarray analysis are more expensive up front but are far more effective in making a genetic diagnosis and much less costly

American Journal of Medical Genetics Part A ◽

10.1002/ajmg.a.38715 ◽

2018 ◽

Vol 176 (5) ◽

pp. 1044-1045

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Microarray Analysis ◽

Genetic Diagnosis ◽

Cost Effective ◽

Chromosomal Microarray ◽

Underserved Population ◽

Chromosomal Microarray Analysis ◽

Whole Exome

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OC21.06: Whole‐exome sequencing and whole‐genome sequencing improves genetic diagnosis of fetuses with heterotaxy syndrome revealed by prenatal ultrasound

Ultrasound in Obstetrics and Gynecology ◽

10.1002/uog.20571 ◽

2019 ◽

Vol 54 (S1) ◽

pp. 55-55

Author(s):

Y. Tong ◽

H. Sun ◽

Y. Fu ◽

X. Gu ◽

Y. He

Keyword(s):

Whole Genome Sequencing ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Genome Sequencing ◽

Genetic Diagnosis ◽

Prenatal Ultrasound ◽

Whole Genome ◽

Heterotaxy Syndrome ◽

Whole Exome

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Whole-exome sequencing gives additional benefits compared to candidate gene sequencing in the molecular diagnosis of children with growth hormone or IGF-1 insensitivity

Acta Endocrinologica ◽

10.1530/eje-17-0453 ◽

2017 ◽

Vol 177 (6) ◽

pp. 485-501 ◽

Cited By ~ 12

Author(s):

Lucy Shapiro ◽

Sumana Chatterjee ◽

Dina G Ramadan ◽

Kate M Davies ◽

Martin O Savage ◽

...

Keyword(s):

Genetic Testing ◽

Candidate Gene ◽

Short Stature ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Genetic Variants ◽

Genetic Defect ◽

Significant Proportion ◽

Genetic Diagnosis ◽

Whole Exome

Background GH insensitivity (GHI) is characterised by short stature, IGF-1 deficiency and normal/elevated serum GH. IGF-1 insensitivity results in pre- and post-natal growth failure with normal/high IGF-1 levels. The prevalence of genetic defects is unknown. Objective To identify the underlying genetic diagnoses in a paediatric cohort with GH or IGF-1 insensitivity using candidate gene (CGS) and whole-exome sequencing (WES) and assess factors associated with the discovery of a genetic defect. Methods We undertook a prospective study of 132 patients with short stature and suspected GH or IGF-1 insensitivity referred to our centre for genetic analysis. 107 (96 GHI, 88 probands; 11 IGF-1 insensitivity, 9 probands) underwent CGS. WES was performed in those with no defined genetic aetiology following CGS. Results A genetic diagnosis was discovered 38/107 (36%) patients (32% probands) by CGS. WES revealed 11 patients with genetic variants in genes known to cause short stature. A further 2 patients had hypomethylation in the H19/IGF2 region or mUPD7 consistent with Silver–Russell Syndrome (total with genetic diagnosis 51/107, 48% or 41/97, 42% probands). WES also identified homozygous putative variants in FANCA and PHKB in 2 patients. Low height SDS and consanguinity were highly predictive for identifying a genetic defect. Conclusions Comprehensive genetic testing confirms the genetic heterogeneity of GH/IGF-1 insensitivity and successfully identified the genetic aetiology in a significant proportion of cases. WES is rapid and may isolate genetic variants that have been missed by traditional clinically driven genetic testing. This emphasises the benefits of specialist diagnostic centres.

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The Promise of Whole-exome Sequencing for Prenatal Genetic Diagnosis

Current Pharmacogenomics and Personalized Medicine ◽

10.2174/1875692117666191106105918 ◽

2020 ◽

Vol 17 (1) ◽

pp. 25-31

Author(s):

Jiun Kang

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Genetic Disorders ◽

Genetic Diagnosis ◽

Chromosomal Microarray ◽

Chromosomal Microarray Analysis ◽

Prognostic Information ◽

Prenatal Genetic Diagnosis ◽

Whole Exome ◽

Nextgeneration Sequencing

Prenatal genetic diagnosis provides information for pregnancy and perinatal decision- making and management. Cytogenetic testing methods, including chromosomal microarray analysis and gene panels, have evolved to become a part of routine laboratory testing, providing valuable diagnostic and prognostic information for prenatal diagnoses. Despite this progress, however, cytogenetic analyses are limited by their resolution and diagnosis is only possible in around 40% of the dysmorphic fetuses. The advent of nextgeneration sequencing (NGS), whole-genome sequencing or whole-exome sequencing has revolutionized prenatal diagnosis and fetal medicine. These technologies have improved the identification of genetic disorders in fetuses with structural abnormalities and provide valuable diagnostic and prognostic information for the detection of genomic defects. Here, the potential future of prenatal genetic diagnosis, including a move toward NGS technologies, is discussed.

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Exome sequencing in paediatric patients with movement disorders

Orphanet Journal of Rare Diseases ◽

10.1186/s13023-021-01688-6 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Anna Ka-Yee Kwong ◽

Mandy Ho-Yin Tsang ◽

Jasmine Lee-Fong Fung ◽

Christopher Chun-Yu Mak ◽

Kate Lok-San Chan ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Movement Disorders ◽

Rare Variants ◽

Diagnostic Yield ◽

Neurological Diseases ◽

Genetic Diagnosis ◽

Potential Treatment ◽

Paediatric Patients ◽

Whole Exome

Abstract Background Movement disorders are a group of heterogeneous neurological diseases including hyperkinetic disorders with unwanted excess movements and hypokinetic disorders with reduction in the degree of movements. The objective of our study is to investigate the genetic etiology of a cohort of paediatric patients with movement disorders by whole exome sequencing and to review the potential treatment implications after a genetic diagnosis. Results We studied a cohort of 31 patients who have paediatric-onset movement disorders with unrevealing etiologies. Whole exome sequencing was performed and rare variants were interrogated for pathogenicity. Genetic diagnoses have been confirmed in 10 patients with disease-causing variants in CTNNB1, SPAST, ATP1A3, PURA, SLC2A1, KMT2B, ACTB, GNAO1 and SPG11. 80% (8/10) of patients with genetic diagnosis have potential treatment implications and treatments have been offered to them. One patient with KMT2B dystonia showed clinical improvement with decrease in dystonia after receiving globus pallidus interna deep brain stimulation. Conclusions A diagnostic yield of 32% (10/31) was reported in our cohort and this allows a better prediction of prognosis and contributes to a more effective clinical management. The study highlights the potential of implementing precision medicine in the patients.

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Analysis workflow to assess de novo genetic variants from human whole-exome sequencing

STAR Protocols ◽

10.1016/j.xpro.2021.100383 ◽

2021 ◽

Vol 2 (1) ◽

pp. 100383

Author(s):

Nicholas S. Diab ◽

Spencer King ◽

Weilai Dong ◽

Garrett Allington ◽

Amar Sheth ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Genetic Variants ◽

De Novo ◽

Whole Exome ◽

Analysis Workflow

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Novel MYO15A variants are associated with hearing loss in the two Iranian pedigrees

BMC Medical Genetics ◽

10.1186/s12881-020-01168-x ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Somayeh Khatami ◽

Masomeh Askari ◽

Fatemeh Bahreini ◽

Morteza Hashemzadeh-Chaleshtori ◽

Saeed Hematian ◽

...

Keyword(s):

Hearing Loss ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Genetic Diagnosis ◽

Clinical Genetic ◽

Large Size ◽

Whole Exome ◽

Novel Variants ◽

Syndromic Hearing Loss ◽

Traditional Approaches

Abstract Background Clinical genetic diagnosis of non-syndromic hearing loss (NSHL) is quite challenging. With regard to its high heterogeneity as well as large size of some genes, it is also really difficult to detect causative mutations using traditional approaches. One of the recent technologies called whole-exome sequencing (WES) has been thus developed in this domain to remove the limitations of conventional methods. Methods This study was a report on a research study of two unrelated pedigrees with multiple affected cases of hearing loss (HL). Accordingly, clinical evaluations and genetic analysis were performed in both families. Results The results of WES data analysis to uncover autosomal recessive non-syndromic hearing loss (ARNSHL) disease-causing variants was reported in the present study. Initial analysis identified two novel variants of MYO15A i.e. c.T6442A:p.W2148R and c.10504dupT:p.C3502Lfs*15 correspondingly which were later confirmed by Sanger validations and segregation analyses. According to online prediction tools, both identified variants seemed to have damaging effects. Conclusion In this study, whole exome sequencing were used as a first approach strategy to identify the two novel variants in MYO15A in two Iranian families with ARNSHL.

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Genetic Diagnosis Using Whole Exome Sequencing in Common Variable Immunodeficiency

Frontiers in Immunology ◽

10.3389/fimmu.2016.00220 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 117

Author(s):

Patrick Maffucci ◽

Charles A. Filion ◽

Bertrand Boisson ◽

Yuval Itan ◽

Lei Shang ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Common Variable Immunodeficiency ◽

Genetic Diagnosis ◽

Whole Exome ◽

Common Variable

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Identification of Two Novel Mutations in PKHD1 Gene from Two Families with Polycystic Kidney Disease by Whole Exome Sequencing

Current Genomics ◽

10.2174/1389202922666210219111810 ◽

2021 ◽

Vol 22 ◽

Author(s):

Masoud Heidari ◽

Hamid Gharshasbi ◽

Alireza Isazadeh ◽

Morteza Soleyman-Nejad ◽

Mohammad Hossein Taskhiri ◽

...

Keyword(s):

Kidney Disease ◽

Exome Sequencing ◽

Polycystic Kidney Disease ◽

Whole Exome Sequencing ◽

Novel Mutation ◽

Genetic Diagnosis ◽

Genetic Alterations ◽

Polycystic Kidney ◽

Novel Mutations ◽

Whole Exome

Background:: Polycystic kidney disease (PKD) is an autosomal recessive disorder resulting from mutations in the PKHD1 gene on chromosome 6 (6p12), a large gene spanning 470 kb of genomic DNA. Objective: The aim of the present study was to report newly identified mutations in the PKHD1 gene in two Iranian families with PKD. Materials and Methods: Genetic alterations of a 3-month-old boy and a 27-year-old girl with PKD were evaluated using whole-exome sequencing. The PCR direct sequencing was performed to analyse the co-segregation of the variants with the disease in the family. Finally, the molecular function of the identified novel mutations was evaluated by in silico study. Results: In the 3 month-old boy, a novel homozygous frameshift mutation was detected in the PKHD1 gene, which can cause PKD. Moreover, we identified three novel heterozygous missense mutations in ATIC, VPS13B, and TP53RK genes. In the 27-year-old woman, with two recurrent abortions history and two infant mortalities at early weeks due to metabolic and/or renal disease, we detected a novel missense mutation on PKHD1 gene and a novel mutation in ETFDH gene. Conclusion: In general, we have identified two novel mutations in the PKHD1 gene. These molecular findings can help accurately correlate genotype and phenotype in families with such disease in order to reduce patient births through preoperative genetic diagnosis or better management of disorders.

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