Whole Exome Sequencing Identifies a Homozygous PYCR1 Missense Variant in a Patient with Autosomal Recessive Cutis Laxa Type 2B: A Case Report

Abstract Background Limb-girdle muscular dystrophies (LGMDs) are large group of heterogeneous genetic diseases, having a hallmark feature of muscle weakness. Pathogenic mutations in the gene encoding the giant skeletal muscle protein titin (TTN) are associated with several muscle disorders, including cardiomyopathy, recessive congenital myopathies and limb-girdle muscular dystrophy (LGMD) type10. The phenotypic spectrum of titinopathies is expanding, as next generation sequencing (NGS) technology makes screening of this large gene possible. Aim This study aimed to identify the pathogenic variant in a consanguineous Pakistani family with autosomal recessive LGMD type 10. Methods DNA from peripheral blood samples were obtained, whole exome sequencing (WES) was performed and several molecular and bioinformatics analysis were conducted to identify the pathogenic variant. TTN coding and near coding regions were further amplified using PCR and sequenced via Sanger sequencing. Results Whole exome sequencing analysis revealed a novel homozygous missense variant (c.98807G > A; p.Arg32936His) in the TTN gene in the index patients. No heterozygous individuals in the family presented LGMD features. The variant p.Arg32936His leads to a substitution of the arginine amino acid at position 32,936 into histidine possibly causing LGMD type 10. Conclusion We identified a homozygous missense variant in TTN, which likely explains LGMD type 10 in this family in line with similar previously reported data. Our study concludes that WES is a successful molecular diagnostic tool to identify pathogenic variants in large genes such as TTN in highly inbred population.

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Case Report: Whole exome sequencing helps in accurate molecular diagnosis in siblings with a rare co-occurrence of paternally inherited 22q12 duplication and autosomal recessive non-syndromic ichthyosis.

F1000Research ◽

10.12688/f1000research.6779.1 ◽

2015 ◽

Vol 4 ◽

pp. 446 ◽

Cited By ~ 3

Author(s):

Aayush Gupta ◽

Yugal Sharma ◽

Kirti Deo ◽

Shamsudheen Vellarikkal ◽

Rijith Jayarajan ◽

...

Keyword(s):

Case Report ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Molecular Diagnosis ◽

Autosomal Recessive ◽

The Body ◽

Finnish Population ◽

Whole Exome ◽

Chromosome Arm ◽

First Time

Lamellar ichthyosis (LI), considered an autosomal recessive monogenic genodermatosis, has an incidence of approximately 1 in 250,000. Usually associated with mutations in the transglutaminase gene (TGM1), mutations in six other genes have, less frequently, been shown to be causative. Two siblings, born in a collodion membrane, presented with fish like scales all over the body. Karyotyping revealed duplication of the chromosome arm on 22q12+ in the father and two siblings. Whole exome sequencing revealed a homozygous p.Gly218Ser variation in TGM1; a variation reported earlier in an isolated Finnish population in association with autosomal recessive non-syndromic ichthyosis. This concurrence of a potentially benign 22q12+ duplication and LI, both rare individually, is reported here likely for the first time.

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Specific Cognitive Changes due to Hippocalcin Alterations? A Novel Familial Homozygous Hippocalcin Variant Associated with Inherited Dystonia and Altered Cognition

Neuropediatrics ◽

10.1055/s-0040-1722686 ◽

2021 ◽

Author(s):

Sandy Siegert ◽

Wolfgang M. Schmidt ◽

Thomas Pletschko ◽

Reginald E. Bittner ◽

Sonja Gobara ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Pediatric Patient ◽

Autosomal Recessive ◽

Family Members ◽

Missense Variant ◽

Index Patient ◽

Cognitive Changes ◽

Her Family ◽

Whole Exome

Abstract Background Recent research suggested an hippocalcin (HPCA)-related form of DYT2-like autosomal recessive dystonia. Two reports highlight a broad spectrum of the clinical phenotype. Here, we describe a novel HPCA gene variant in a pediatric patient and two affected relatives. Methods Whole exome sequencing was applied after a thorough clinical and neurological examination of the index patient and her family members. Results of neuropsychological testing were analyzed. Results Whole exome sequencing revealed a novel homozygous missense variant in the HPCA gene [c.182C>T p.(Ala61Val)] in our pediatric patient and the two affected family members. Clinically, the cases presented with dystonia, dysarthria, and jerky movements. We observed a particular cognitive profile with executive dysfunctions in our patient, which corresponds to the cognitive deficits that have been observed in the patients previously described. Conclusion We present a novel genetic variant of the HPCA gene associated with autosomal recessive dystonia in a child with childhood-onset dystonia supporting its clinical features. Furthermore, we propose specific HPCA-related cognitive changes in homozygous carriers, underlining the importance of undertaking a systematic assessment of cognition in HPCA-related dystonia.

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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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Whole exome sequencing identifies FOXL2, FOXA2 and FOXA3 as candidate genes for monogenic congenital anomalies of the kidneys and urinary tract

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfab253 ◽

2021 ◽

Author(s):

Bixia Zheng ◽

Steve Seltzsam ◽

Chunyan Wang ◽

Luca Schierbaum ◽

Sophia Schneider ◽

...

Keyword(s):

Urinary Tract ◽

Exome Sequencing ◽

Candidate Genes ◽

Whole Exome Sequencing ◽

Congenital Anomalies ◽

De Novo ◽

Horseshoe Kidney ◽

Missense Variant ◽

Whole Exome ◽

Fox Genes

Abstract Background Congenital anomalies of the kidneys and urinary tract (CAKUT) constitute the most common cause of chronic kidney disease in the first three decades of life. Variants in four Forkhead box (FOX) transcription factors have been associated with CAKUT. We hypothesized that other FOX genes, if highly expressed in developing kidney, may also represent monogenic causes of CAKUT. Methods We here performed whole exome sequencing (WES) in 541 families with CAKUT and generated 4 lists of CAKUT candidate genes: A) 36 FOX genes showing high expression during renal development, B) 4 FOX genes known to cause CAKUT to validate list A; C) 80 genes that we identified as unique potential novel CAKUT candidate genes when performing WES in 541 CAKUT families, and D) 175 genes identified from WES as multiple potential novel CAKUT candidate genes. Results To prioritize potential novel CAKUT candidates in FOX gene family, we overlapped 36 FOX genes (list A) with list C and D of WES-derived CAKUT candidates. Intersection with list C, identified a de novo FOXL2 in-frame deletion in a patient with eyelid abnormalities and ureteropelvic junction obstruction, and a homozygous FOXA2 missense variant in a patient with horseshoe kidney. Intersection with list D, identified a heterozygous FOXA3 missense variant in a CAKUT family with multiple affected individuals. Conclusion We hereby identified FOXL2, FOXA2 and FOXA3 as novel monogenic candidate genes of CAKUT, supporting the utility of a paralog-based approach to discover mutated genes associated with human disease.

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RHOBTB2 p.Arg511Trp Mutation in Early Infantile Epileptic Encephalopathy-64: Review and Case Report

Journal of Pediatric Genetics ◽

10.1055/s-0040-1722288 ◽

2021 ◽

Author(s):

J Fonseca ◽

C Melo ◽

C Ferreira ◽

M Sampaio ◽

R Sousa ◽

...

Keyword(s):

Case Report ◽

Intellectual Disability ◽

Status Epilepticus ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Epileptic Encephalopathy ◽

Btb Domain ◽

Pathogenic Variants ◽

Severe Intellectual Disability ◽

Whole Exome

AbstractEarly infantile epileptic encephalopathy-64 (EIEE 64), also called RHOBTB2-related developmental and epileptic encephalopathy (DEE), is caused by heterozygous pathogenic variants (EIEE 64; MIM#618004) in the Rho-related BTB domain-containing protein 2 (RHOBTB2) gene. To date, only 13 cases with RHOBTB2-related DEE have been reported. We add to the literature the 14th case of EIEE 64, identified by whole exome sequencing, caused by a heterozygous pathogenic variant in RHOBTB2 (c.1531C > T), p.Arg511Trp. This additional case supports the main features of RHOBTB2-related DEE: infantile-onset seizures, severe intellectual disability, impaired motor functions, postnatal microcephaly, recurrent status epilepticus, and hemiparesis after seizures.

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A homozygous mutation of GNRHR in a familial case diagnosed with polycystic ovary syndrome

Acta Endocrinologica ◽

10.1530/eje-16-0968 ◽

2017 ◽

Vol 176 (5) ◽

pp. K9-K14 ◽

Cited By ~ 5

Author(s):

Sandrine Caburet ◽

Ronit Beck Fruchter ◽

Bérangère Legois ◽

Marc Fellous ◽

Stavit Shalev ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Sanger Sequencing ◽

Polycystic Ovary ◽

Missense Variant ◽

Genetic Alterations ◽

Homozygous Mutation ◽

Gonadotropin Secretion ◽

Whole Exome ◽

A Genome

Context PCOS is a heterogeneous condition characterized by hyperandrogenism and chronic anovulation and affects about 10% of women. Its etiology is poorly known, but a dysregulation of gonadotropin secretion is one of its hallmarks. Objective As the etiology of PCOS is unclear, we have performed a genome-wide analysis of a consanguineous family with three sisters diagnosed with PCOS. Methods Whole-exome sequencing and Sanger sequencing confirmation. Results Whole-exome sequencing allowed the detection of the missense variant rs104893836 located in the first coding exon of the GNRHR gene and leading to the p.Gln106Arg (p.Q106R) substitution. Sanger sequencing of all available individuals of the family confirmed that the variant was homozygous in the three affected sisters and heterozygous in both parents. Conclusions This is the first description of a GNRHR gene mutation in patients diagnosed with PCOS. Although we do not exclude a possible interaction of the identified variant with the genetic background and/or the environment, our result suggests that genetic alterations in the hypothalamo–pituitary axis may play role in the pathogenesis of PCOS.

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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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Ablepharon macrostomia syndrome in a Thai patient: case report and literature review

Asian Biomedicine ◽

10.1515/abm-2020-0012 ◽

2020 ◽

Vol 14 (2) ◽

pp. 83-88

Author(s):

Phawin Kor-anantakul ◽

Kanya Suphapeetiporn ◽

Somchit Jaruratanasirikul

Keyword(s):

Case Report ◽

Literature Review ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Sequencing Analysis ◽

Patient Case ◽

Thai Patient ◽

Labia Minora ◽

Whole Exome ◽

Rare Congenital Disorder

AbstractAblepharon macrostomia syndrome (AMS) is a rare congenital disorder. To our knowledge, only 20 cases have been reported to date, and all in patients from Western countries. We report a case of AMS in a Thai patient, who presented at age 3 months with severe ectropion of both upper and lower eyelids, alopecia totalis, no palpable clitoris, and hypoplasia of both labia minora and labia majora. Trio whole exome sequencing analysis was performed, which revealed a heterozygous missense c.223G>A (p.Glu75Lys) variation in TWIST2. To our knowledge, this is the first reported case of AMS in a patient from Thailand and the first reported case of AMS in Asia.

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