Whole-Exome Sequencing Identifies Novel Variants that Co-segregates with Autosomal Recessive Retinal Degeneration in a Pakistani Pedigree

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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Whole-exome sequencing identifies a novel missense mutation in EDAR causing autosomal recessive hypohidrotic ectodermal dysplasia with bilateral amastia and palmoplantar hyperkeratosis

British Journal of Dermatology ◽

10.1111/bjd.12151 ◽

2013 ◽

Vol 168 (6) ◽

pp. 1353-1356 ◽

Cited By ~ 10

Author(s):

A. Haghighi ◽

P. Nikuei ◽

H. Haghighi-Kakhki ◽

N. Saleh-Gohari ◽

S. Baghestani ◽

...

Keyword(s):

Exome Sequencing ◽

Missense Mutation ◽

Whole Exome Sequencing ◽

Autosomal Recessive ◽

Ectodermal Dysplasia ◽

Hypohidrotic Ectodermal Dysplasia ◽

Whole Exome ◽

Palmoplantar Hyperkeratosis

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Prescreening whole exome sequencing results from patients with retinal degeneration for variants in genes associated with retinal degeneration

Clinical Ophthalmology ◽

10.2147/opth.s147684 ◽

2017 ◽

Vol Volume 12 ◽

pp. 49-63 ◽

Cited By ~ 4

Author(s):

Laura Bryant ◽

Olga Lozynska ◽

Albert Maguire ◽

Tomas Aleman ◽

Jean Bennett

Keyword(s):

Exome Sequencing ◽

Retinal Degeneration ◽

Whole Exome Sequencing ◽

Whole Exome

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Whole-Exome Sequencing Identifies Novel Variants for Tooth Agenesis

Journal of Dental Research ◽

10.1177/0022034517724149 ◽

2017 ◽

Vol 97 (1) ◽

pp. 49-59 ◽

Cited By ~ 16

Author(s):

N. Dinckan ◽

R. Du ◽

L.E. Petty ◽

Z. Coban-Akdemir ◽

S.N. Jhangiani ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Permanent Teeth ◽

Tooth Agenesis ◽

Disease Genes ◽

Nonsense Mediated Decay ◽

Pathogenic Variants ◽

Whole Exome ◽

Novel Variants ◽

Complex Inheritance

Tooth agenesis is a common craniofacial abnormality in humans and represents failure to develop 1 or more permanent teeth. Tooth agenesis is complex, and variations in about a dozen genes have been reported as contributing to the etiology. Here, we combined whole-exome sequencing, array-based genotyping, and linkage analysis to identify putative pathogenic variants in candidate disease genes for tooth agenesis in 10 multiplex Turkish families. Novel homozygous and heterozygous variants in LRP6, DKK1, LAMA3, and COL17A1 genes, as well as known variants in WNT10A, were identified as likely pathogenic in isolated tooth agenesis. Novel variants in KREMEN1 were identified as likely pathogenic in 2 families with suspected syndromic tooth agenesis. Variants in more than 1 gene were identified segregating with tooth agenesis in 2 families, suggesting oligogenic inheritance. Structural modeling of missense variants suggests deleterious effects to the encoded proteins. Functional analysis of an indel variant (c.3607+3_6del) in LRP6 suggested that the predicted resulting mRNA is subject to nonsense-mediated decay. Our results support a major role for WNT pathways genes in the etiology of tooth agenesis while revealing new candidate genes. Moreover, oligogenic cosegregation was suggestive for complex inheritance and potentially complex gene product interactions during development, contributing to improved understanding of the genetic etiology of familial tooth agenesis.

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Whole-exome sequencing reveals POC5 as a novel gene associated with autosomal recessive retinitis pigmentosa

Human Molecular Genetics ◽

10.1093/hmg/ddx428 ◽

2017 ◽

Vol 27 (4) ◽

pp. 614-624 ◽

Cited By ~ 9

Author(s):

Monika Weisz Hubshman ◽

Sanne Broekman ◽

Erwin van Wijk ◽

Frans Cremers ◽

Alaa Abu-Diab ◽

...

Keyword(s):

Retinitis Pigmentosa ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Autosomal Recessive ◽

Novel Gene ◽

Whole Exome

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Whole‐Exome Sequencing of a Saudi Epilepsy Cohort Reveals Association Signals in Known and Potentially Novel Loci

10.21203/rs.3.rs-915593/v1 ◽

2021 ◽

Author(s):

Amein Kadhem AlAli ◽

Abdulrahman Al-Enazi ◽

Ahmed Ammar ◽

Mahmoud Hajj ◽

Cyril Cyrus ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Rare Variants ◽

High Rate ◽

Variants Of Unknown Significance ◽

Pathogenic Variants ◽

Whole Exome ◽

Novel Variants ◽

Unknown Significance ◽

Rare Genetic Variants

Abstract Background Epilepsy, a serious chronic neurological condition effecting up to 100 million people globally, has clear genetic underpinnings including common and rare variants. In Saudi Arabia the prevalence of epilepsy is high and caused mainly by perinatal and genetic factors. No whole-exome sequencing (WES) studies have been performed to date in Saudi Arabian Epilepsy cohorts. This offers a unique opportunity for the discovery of rare genetic variants impacting this disease as there is a high rate of consanguinity amongst large tribal pedigrees. Results We performed WES on 144 individuals diagnosed with epilepsy, to interrogate known Epilepsy related genes for known and functional novel variants. We also used an American College of Medical Genetics (ACMG) guideline based variant prioritization approach in an attempt to discover putative causative variants. We identified a 32 potentially causative pathogenic variants across 30 different genes in 44/144 (30%) of these Saudi Epilepsy individuals. We also identified 232 variants of unknown significance (VUS) across 101 different genes in 133/144 (92%) subjects. Strong enrichment of variants of likely pathogenicity were observed in previously described epilepsy-associated loci, and a number of putative pathogenic variants in novel loci are also observed. Conclusion Several putative pathogenic variants known to be epilepsy-related loci were identified for the first time in our population, in addition to several potential new loci have been identified which may be prioritized for further investigation.

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Whole exome sequencing identified a homozygous novel mutation in SUOX gene causes extremely rare autosomal recessive isolated sulfite oxidase deficiency and literature review

10.21203/rs.3.rs-74199/v3 ◽

2021 ◽

Author(s):

Rui Zhang ◽

Yajing Hao ◽

Ying Xu ◽

Jiale Qin ◽

Yanfang Wang ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Autosomal Recessive ◽

Novel Mutation ◽

Sulfite Oxidase ◽

Loss Of Function ◽

Oxidase Deficiency ◽

Neurometabolic Disorders ◽

Whole Exome ◽

Sulfite Oxidase Deficiency

Abstract Background: Isolated sulfite oxidase deficiency (ISOD) is the rarest types of life-threatening neurometabolic disorders characterized by neonatal intractable seizures and severe developmental delay with an autosomal recessive mode of inheritance. ISOD is extremely rare and till date only 32 mutations have been identified and reported worldwide. Germline mutation in SUOX gene causes ISOD. Methods: Here, we investigated a 5-days old Chinese female child, presented with intermittent tremor or seizures of limbs, neonatal encephalopathy, subarachnoid cyst and haemorrhage, dysplasia of corpus callosum, neonatal convulsion, respiratory failure, cardiac failure, hyperlactatemia, severe metabolic acidosis, hyperglycemia, hyperkalemia, moderate anemia, atrioventricular block and complete right bundle branch block. Results: Whole exome sequencing identified a novel homozygous transition (c.1227G>A) in exon 6 of the SUOX gene in the proband. This novel homozygous variant leads to the formation of a truncated sulfite oxidase (p.Trp409*) of 408 amino acids. Hence, it is a loss-of-function variant. Proband’s father and mother is carrying this novel variant in a heterozygous state. This variant was not identified in 200 ethnically matched normal healthy control individuals. Conclusions: Our study not only expand the mutational spectrum of SUOX gene associated ISOD, but also strongly suggested the application of whole exome sequencing for identifying candidate genes and novel disease-causing mutations.

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Whole Exome Sequencing of Six Chinese Families With Hereditary Non-Syndromic Hearing Loss: A Genetic Etiology Study

10.21203/rs.3.rs-132767/v1 ◽

2020 ◽

Author(s):

Pengfei Liang ◽

Fengping Chen ◽

Shujuan Wang ◽

Qiong Li ◽

Wei Li ◽

...

Keyword(s):

Hearing Loss ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Sanger Sequencing ◽

Large Scale ◽

Autosomal Recessive ◽

Autosomal Recessive Inheritance ◽

Chinese Families ◽

Whole Exome ◽

Syndromic Hearing Loss

Abstract Background: Hereditary non-syndromic hearing loss (NSHL) has a high genetic heterogeneity with >152 genes identified as associated molecular causes. The present study aimed to detect the possible damaging variants of the deaf probands from six unrelated Chinese families.Methods: After excluding the mutations in the most common genes, GJB2 and SLC26A4, 12 probands with prelingual deafness and autosomal recessive inheritance were evaluated by whole-exome sequencing (WES). All the candidate variants were verified by Sanger sequencing in all patients and their parents.Results: Biallelic mutations were identified in all deaf patients. Among these six families, 10 potentially causative mutations, including 3 reported and 7 novel mutations, in 3 different deafness-associated autosomal recessive (DFNB) genes (MYO15A, COL11A2, and CDH23) were identified. The mutations in MYO15A were frequent with 7/10 candidate variants. Sanger sequencing confirmed that these mutations segregated with the hearing loss of each family.Conclusions: Next-generation sequencing (NGS) approach becomes more cost-effective and efficient when analyzing large-scale genes compared to the conventional polymerase chain reaction-based Sanger sequencing, which is often used to screen common deafness-related genes. The current findings further extend the mutation spectrum of hearing loss in the Chinese population, which has a positive significance for genetic counseling.

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Juberg-Hayward syndrome is a cohesinopathy, caused by mutation in ESCO2

European Journal of Orthodontics ◽

10.1093/ejo/cjaa023 ◽

2020 ◽

Author(s):

Piranit Nik Kantaputra ◽

Prapai Dejkhamron ◽

Worrachet Intachai ◽

Chumpol Ngamphiw ◽

Katsushige Kawasaki ◽

...

Keyword(s):

Short Stature ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Upper Limb ◽

Autosomal Recessive ◽

Cleft Lip ◽

Clinical Findings ◽

Protein Model ◽

Whole Exome ◽

Cleft Lip Palate

Summary Background Juberg-Hayward syndrome (JHS; MIM 216100) is a rare autosomal recessive malformation syndrome, characterized by cleft lip/palate, microcephaly, ptosis, short stature, hypoplasia or aplasia of thumbs, and dislocation of radial head and fusion of humerus and radius leading to elbow restriction. Objective To report for the first time the molecular aetiology of JHS. Patient and methods Clinical and radiographic examination, whole exome sequencing, Sanger sequencing, mutant protein model construction, and in situ hybridization of Esco2 expression in mouse embryos were performed. Results Clinical findings of the patient consisted of repaired cleft lip/palate, microcephaly, ptosis, short stature, delayed bone age, hypoplastic fingers and thumbs, clinodactyly of the fifth fingers, and humeroradial synostosis leading to elbow restriction. Intelligence is normal. Whole exome sequencing of the whole family showed a novel homozygous base substitution c.1654C>T in ESCO2 of the proband. The sister was homozygous for the wildtype variant. Parents were heterozygous for the mutation. The mutation is predicted to cause premature stop codon p.Arg552Ter. Mutations in ESCO2, a gene involved in cohesin complex formation, are known to cause Roberts/SC phocomelia syndrome. Roberts/SC phocomelia syndrome and JHS share similar clinical findings, including autosomal recessive inheritance, short stature, cleft lip/palate, severe upper limb anomalies, and hypoplastic digits. Esco2 expression during the early development of lip, palate, eyelid, digits, upper limb, and lower limb and truncated protein model are consistent with the defect. Conclusions Our study showed that Roberts/SC phocomelia syndrome and JHS are allelic and distinct entities. This is the first report demonstrating that mutation in ESCO2 causes JHS, a cohesinopathy.

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