1
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Farris J, Khanna C, Smadbeck JB, Johnson SH, Bothun E, Kaplan T, Hoffman F, Polonis K, Oliver G, Reis LM, Semina EV, Rust L, Hoppman NL, Vasmatzis G, Marcou CA, Schimmenti LA, Klee EW. Complex balanced intrachromosomal rearrangement involving PITX2 identified as a cause of Axenfeld-Rieger Syndrome. Am J Med Genet A 2024; 194:e63542. [PMID: 38234180 PMCID: PMC11003841 DOI: 10.1002/ajmg.a.63542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/15/2023] [Accepted: 01/07/2024] [Indexed: 01/19/2024]
Abstract
Axenfeld-Rieger Syndrome (ARS) type 1 is a rare autosomal dominant condition characterized by anterior chamber anomalies, umbilical defects, dental hypoplasia, and craniofacial anomalies, with Meckel's diverticulum in some individuals. Here, we describe a clinically ascertained female of childbearing age with ARS for whom clinical targeted sequencing and deletion/duplication analysis followed by clinical exome and genome sequencing resulted in no pathogenic variants or variants of unknown significance in PITX2 or FOXC1. Advanced bioinformatic analysis of the genome data identified a complex, balanced rearrangement disrupting PITX2. This case is the first reported intrachromosomal rearrangement leading to ARS, illustrating that for patients with compelling clinical phenotypes but negative genomic testing, additional bioinformatic analysis are essential to identify subtle genomic abnormalities in target genes.
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Affiliation(s)
- Joseph Farris
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Cheryl Khanna
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - James B Smadbeck
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Sarah H Johnson
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Erick Bothun
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Tyler Kaplan
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Francis Hoffman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Katarzyna Polonis
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Gavin Oliver
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Linda M Reis
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Wisconsin, Milwaukee, Wisconsin, USA
| | - Elena V Semina
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Wisconsin, Milwaukee, Wisconsin, USA
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Laura Rust
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota, USA
| | - Nicole L Hoppman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - George Vasmatzis
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota, USA
| | - Cherisse A Marcou
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Lisa A Schimmenti
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota, USA
| | - Eric W Klee
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota, USA
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2
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Gilbertson EN, Brand CM, McArthur E, Rinker DC, Kuang S, Pollard KS, Capra JA. Machine learning reveals the diversity of human 3D chromatin contact patterns. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573104. [PMID: 38187606 PMCID: PMC10769343 DOI: 10.1101/2023.12.22.573104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Understanding variation in chromatin contact patterns across human populations is critical for interpreting non-coding variants and their ultimate effects on gene expression and phenotypes. However, experimental determination of chromatin contacts at a population-scale is prohibitively expensive. To overcome this challenge, we develop and validate a machine learning method to quantify the diversity 3D chromatin contacts at 2 kilobase resolution from genome sequence alone. We then apply this approach to thousands of diverse modern humans and the inferred human-archaic hominin ancestral genome. While patterns of 3D contact divergence genome-wide are qualitatively similar to patterns of sequence divergence, we find that 3D divergence in local 1-megabase genomic windows does not follow sequence divergence. In particular, we identify 392 windows with significantly greater 3D divergence than expected from sequence. Moreover, 26% of genomic windows have rare 3D contact variation observed in a small number of individuals. Using in silico mutagenesis we find that most sequence changes to do not result in changes to 3D chromatin contacts. However in windows with substantial 3D divergence, just one or a few variants can lead to divergent 3D chromatin contacts without the individuals carrying those variants having high sequence divergence. In summary, inferring 3D chromatin contact maps across human populations reveals diverse contact patterns. We anticipate that these genetically diverse maps of 3D chromatin contact will provide a reference for future work on the function and evolution of 3D chromatin contact variation across human populations.
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Affiliation(s)
- Erin N Gilbertson
- Biomedical Informatics Graduate Program, University of California San Francisco, San Francisco, CA
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA
| | - Colin M Brand
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA
| | - Evonne McArthur
- Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN
- Department of Medicine, University of Washington, Seattle, WA
| | - David C Rinker
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
| | - Shuzhen Kuang
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA
| | - Katherine S Pollard
- Biomedical Informatics Graduate Program, University of California San Francisco, San Francisco, CA
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA
- Chan Zuckerberg Biohub SF, San Francisco, CA
| | - John A Capra
- Biomedical Informatics Graduate Program, University of California San Francisco, San Francisco, CA
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA
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3
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Zug R, Uller T. Evolution and dysfunction of human cognitive and social traits: A transcriptional regulation perspective. EVOLUTIONARY HUMAN SCIENCES 2022; 4:e43. [PMID: 37588924 PMCID: PMC10426018 DOI: 10.1017/ehs.2022.42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 08/11/2022] [Accepted: 09/11/2022] [Indexed: 11/07/2022] Open
Abstract
Evolutionary changes in brain and craniofacial development have endowed humans with unique cognitive and social skills, but also predisposed us to debilitating disorders in which these traits are disrupted. What are the developmental genetic underpinnings that connect the adaptive evolution of our cognition and sociality with the persistence of mental disorders with severe negative fitness effects? We argue that loss of function of genes involved in transcriptional regulation represents a crucial link between the evolution and dysfunction of human cognitive and social traits. The argument is based on the haploinsufficiency of many transcriptional regulator genes, which makes them particularly sensitive to loss-of-function mutations. We discuss how human brain and craniofacial traits evolved through partial loss of function (i.e. reduced expression) of these genes, a perspective compatible with the idea of human self-domestication. Moreover, we explain why selection against loss-of-function variants supports the view that mutation-selection-drift, rather than balancing selection, underlies the persistence of psychiatric disorders. Finally, we discuss testable predictions.
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Affiliation(s)
- Roman Zug
- Department of Biology, Lund University, Lund, Sweden
| | - Tobias Uller
- Department of Biology, Lund University, Lund, Sweden
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4
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Candido-Ferreira IL, Lukoseviciute M, Sauka-Spengler T. Multi-layered transcriptional control of cranial neural crest development. Semin Cell Dev Biol 2022; 138:1-14. [PMID: 35941042 DOI: 10.1016/j.semcdb.2022.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 07/23/2022] [Accepted: 07/23/2022] [Indexed: 11/28/2022]
Abstract
The neural crest (NC) is an emblematic population of embryonic stem-like cells with remarkable migratory ability. These distinctive attributes have inspired the curiosity of developmental biologists for over 150 years, however only recently the regulatory mechanisms controlling the complex features of the NC have started to become elucidated at genomic scales. Regulatory control of NC development is achieved through combinatorial transcription factor binding and recruitment of associated transcriptional complexes to distal cis-regulatory elements. Together, they regulate when, where and to what extent transcriptional programmes are actively deployed, ultimately shaping ontogenetic processes. Here, we discuss how transcriptional networks control NC ontogeny, with a special emphasis on the molecular mechanisms underlying specification of the cephalic NC. We also cover emerging properties of transcriptional regulation revealed in diverse developmental systems, such as the role of three-dimensional conformation of chromatin, and how they are involved in the regulation of NC ontogeny. Finally, we highlight how advances in deciphering the NC transcriptional network have afforded new insights into the molecular basis of human diseases.
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Affiliation(s)
- Ivan L Candido-Ferreira
- University of Oxford, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford OX3 9DS, UK
| | - Martyna Lukoseviciute
- University of Oxford, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford OX3 9DS, UK
| | - Tatjana Sauka-Spengler
- University of Oxford, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, Oxford OX3 9DS, UK.
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5
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Boyling A, Perez-Siles G, Kennerson ML. Structural Variation at a Disease Mutation Hotspot: Strategies to Investigate Gene Regulation and the 3D Genome. Front Genet 2022; 13:842860. [PMID: 35401663 PMCID: PMC8990796 DOI: 10.3389/fgene.2022.842860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 02/21/2022] [Indexed: 12/18/2022] Open
Abstract
A rare form of X-linked Charcot-Marie-Tooth neuropathy, CMTX3, is caused by an interchromosomal insertion occurring at chromosome Xq27.1. Interestingly, eight other disease phenotypes have been associated with insertions (or insertion-deletions) occurring at the same genetic locus. To date, the pathogenic mechanism underlying most of these diseases remains unsolved, although local gene dysregulation has clearly been implicated in at least two phenotypes. The challenges of accessing disease-relevant tissue and modelling these complex genomic rearrangements has led to this research impasse. We argue that recent technological advancements can overcome many of these challenges, particularly induced pluripotent stem cells (iPSC) and their capacity to provide access to patient-derived disease-relevant tissue. However, to date these valuable tools have not been utilized to investigate the disease-associated insertions at chromosome Xq27.1. Therefore, using CMTX3 as a reference disease, we propose an experimental approach that can be used to explore these complex mutations, as well as similar structural variants located elsewhere in the genome. The mutational hotspot at Xq27.1 is a valuable disease paradigm with the potential to improve our understanding of the pathogenic consequences of complex structural variation, and more broadly, refine our knowledge of the multifaceted process of long-range gene regulation. Intergenic structural variation is a critically understudied class of mutation, although it is likely to contribute significantly to unsolved genetic disease.
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Affiliation(s)
- Alexandra Boyling
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- *Correspondence: Alexandra Boyling, ; Marina L. Kennerson,
| | - Gonzalo Perez-Siles
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Marina L. Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia
- Molecular Medicine Laboratory, Concord Repatriation General Hospital, Sydney, NSW, Australia
- *Correspondence: Alexandra Boyling, ; Marina L. Kennerson,
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6
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Grochowski CM, Krepischi ACV, Eisfeldt J, Du H, Bertola DR, Oliveira D, Costa SS, Lupski JR, Lindstrand A, Carvalho CMB. Chromoanagenesis Event Underlies a de novo Pericentric and Multiple Paracentric Inversions in a Single Chromosome Causing Coffin-Siris Syndrome. Front Genet 2021; 12:708348. [PMID: 34512724 PMCID: PMC8427664 DOI: 10.3389/fgene.2021.708348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/23/2021] [Indexed: 02/02/2023] Open
Abstract
Chromoanagenesis is a descriptive term that encompasses classes of catastrophic mutagenic processes that generate localized and complex chromosome rearrangements in both somatic and germline genomes. Herein, we describe a 5-year-old female presenting with a constellation of clinical features consistent with a clinical diagnosis of Coffin–Siris syndrome 1 (CSS1). Initial G-banded karyotyping detected a 90-Mb pericentric and a 47-Mb paracentric inversion on a single chromosome. Subsequent analysis of short-read whole-genome sequencing data and genomic optical mapping revealed additional inversions, all clustered on chromosome 6, one of them disrupting ARID1B for which haploinsufficiency leads to the CSS1 disease trait (MIM:135900). The aggregate structural variant data show that the resolved, the resolved derivative chromosome architecture presents four de novo inversions, one pericentric and three paracentric, involving six breakpoint junctions in what appears to be a shuffling of genomic material on this chromosome. Each junction was resolved to nucleotide-level resolution with mutational signatures suggestive of non-homologous end joining. The disruption of the gene ARID1B is shown to occur between the fourth and fifth exon of the canonical transcript with subsequent qPCR studies confirming a decrease in ARID1B expression in the patient versus healthy controls. Deciphering the underlying genomic architecture of chromosomal rearrangements and complex structural variants may require multiple technologies and can be critical to elucidating the molecular etiology of a patient’s clinical phenotype or resolving unsolved Mendelian disease cases.
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Affiliation(s)
- Christopher M Grochowski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Ana C V Krepischi
- Department of Genetics and Evolutionary Biology, Human Genome and Stem Cell Research Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Jesper Eisfeldt
- Department of Molecular Medicine and Surgery and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Science for Life Laboratory, Karolinska Institutet Science Park, Solna, Sweden
| | - Haowei Du
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Debora R Bertola
- Department of Genetics and Evolutionary Biology, Human Genome and Stem Cell Research Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.,Clinical Genetics Unit, Instituto da Criança do Hospital das Clínicas, University of São Paulo, São Paulo, Brazil
| | - Danyllo Oliveira
- Department of Genetics and Evolutionary Biology, Human Genome and Stem Cell Research Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Silvia S Costa
- Department of Genetics and Evolutionary Biology, Human Genome and Stem Cell Research Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, United States.,Texas Children's Hospital, Houston, TX, United States
| | - Anna Lindstrand
- Department of Molecular Medicine and Surgery and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Claudia M B Carvalho
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Pacific Northwest Research Institute, Seattle, WA, United States
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7
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Rekler D, Kalcheim C. From Neural Crest to Definitive Roof Plate: The Dynamic Behavior of the Dorsal Neural Tube. Int J Mol Sci 2021; 22:3911. [PMID: 33920095 PMCID: PMC8070085 DOI: 10.3390/ijms22083911] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 01/11/2023] Open
Abstract
Research on the development of the dorsal neural tube is particularly challenging. In this highly dynamic domain, a temporal transition occurs between early neural crest progenitors that undergo an epithelial-to-mesenchymal transition and exit the neural primordium, and the subsequent roof plate, a resident epithelial group of cells that constitutes the dorsal midline of the central nervous system. Among other functions, the roof plate behaves as an organizing center for the generation of dorsal interneurons. Despite extensive knowledge of the formation, emigration and migration of neural crest progenitors, little is known about the mechanisms leading to the end of neural crest production and the transition into a roof plate stage. Are these two mutually dependent or autonomously regulated processes? Is the generation of roof plate and dorsal interneurons induced by neural tube-derived factors throughout both crest and roof plate stages, respectively, or are there differences in signaling properties and responsiveness as a function of time? In this review, we discuss distinctive characteristics of each population and possible mechanisms leading to the shift between the above cell types.
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Affiliation(s)
| | - Chaya Kalcheim
- Department of Medical Neurobiology, Institute of Medical Research Israel-Canada (IMRIC) and the Edmond and Lily Safra Center for Brain Sciences (ELSC), Hebrew University of Jerusalem-Hadassah Medical School, P.O.Box 12272, Jerusalem 9112102, Israel;
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8
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Gershon MD. Hirschsprung disease and more: dysregulation of ERBB2 and ERBB3. J Clin Invest 2021; 131:146389. [PMID: 33720042 DOI: 10.1172/jci146389] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The enteric nervous system mediates reflexes independently of the brain and spinal cord and transmits signals bidirectionally between the gut and the brain. Hirschsprung disease and chronic intestinal pseudo-obstruction (CIPO) and pediatric CIPO are examples of congenital defects that impair gastrointestinal motility. In this issue of the JCI, Thuy-Linh Le et al. analyzed eight patients with defects in tissue that arose from the neural crest. The patients carried homozygous or heterozygous variants in ERBB3 or ERBB2, which encode transmembrane epidermal growth factor receptors that bind neuroregulin 1 (NRG1). Notably, the genetic variants resulted in loss of function with decreased expression or aberrant phosphorylation of the ERBB3/ERBB2 receptors. Experiments using mice revealed that Erbb3 and Erbb2 were expressed in enteric neuronal progenitor cells. This study is an outstanding example of descriptive observation that begs for mechanistic exploration to reveal precisely how the NRG1/ERBB3/ERBB2 pathway influences ENS development.
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9
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Bergant G, Maver A, Peterlin B. Whole-Genome Sequencing in Diagnostics of Selected Slovenian Undiagnosed Patients with Rare Disorders. Life (Basel) 2021; 11:life11030205. [PMID: 33807868 PMCID: PMC8001615 DOI: 10.3390/life11030205] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/24/2021] [Accepted: 03/01/2021] [Indexed: 11/16/2022] Open
Abstract
Several patients with rare genetic disorders remain undiagnosed following comprehensive diagnostic testing using whole-exome sequencing (WES). In these patients, pathogenic genetic variants may reside in intronic or regulatory regions or they may emerge through mutational mechanisms not detected by WES. For this reason, we implemented whole-genome sequencing (WGS) in routine clinical diagnostics of patients with undiagnosed genetic disorders and report on the outcome in 30 patients. Criteria for consideration included (1) negative WES, (2) a high likelihood of a genetic cause for the disorders, (3) positive family history, (4) detection of large blocks of homozygosity or (5) detection of a single pathogenic variant in a gene associated with recessive conditions. We successfully discovered a causative genetic variant in 6 cases, a retrotranspositional event in the APC gene, non-coding variants in the intronic region of the OTC gene and the promotor region of the UFM1 gene, repeat expansion in the RFC1 gene and a single exon duplication in the CNGB3 gene. We also discovered one coding variant, an indel, which was missed by variant caller during WES data analysis. Our study demonstrates the impact of WGS in the group of patients with undiagnosed genetic diseases after WES in the clinical setting and the diversity of mutational mechanisms discovered, which would remain undetected using other methods.
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10
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Maya I, Kahana S, Agmon-Fishman I, Klein C, Matar R, Berger R, Josefsberg SBY, Shohat M, Marom D, Basel-Salmon L, Sagi-Dain L. The phenotype of 15 cases with rare 8q24.13-q24.3 deletions-A new syndrome or still an enigma? Am J Med Genet A 2021; 185:1461-1467. [PMID: 33619900 DOI: 10.1002/ajmg.a.62131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 01/26/2021] [Accepted: 02/06/2021] [Indexed: 11/10/2022]
Abstract
Diagnosis of rare copy number variants (CNVs) with scarce literature evidence poses a major challenge for interpretation of the clinical significance of chromosomal microarray analysis (CMA) results, especially in the prenatal setting. Bioinformatic tools can be used to assist in this issue; however, this prediction can be imprecise. Our objective was to describe the phenotype of the rare copy number losses encompassing the 8q24.13-q24.3 locus, and to find common features in terms of genomic coordinates, gene content, and clinical phenotypic characteristics. Appropriate cases were retrieved using local databases of two largest Israeli centers performing CMA analysis. In addition, literature and public databases search was performed. Local database search yielded seven new patients with del (8)(q24.13q24.3) (one of these with an additional copy number variant). Literature and public databases search yielded eight additional patients. The cases showed high phenotypic variability, ranging from asymptomatic adults and fetuses with normal ultrasound to patients with autism/developmental delay (6/11 postnatal cases, 54.5%). No clear association was noted between the specific disease-causing/high-pLI gene content of the described del (8)(q24.13q24.3) to neurodevelopmental disorders, except for a possibly relevant locus encompassing the KCNQ3 gene. We present the challenges in classification of rare variants with limited clinical information. In such cases, genotype-phenotype correlation must be assessed with extra-caution and possibly using additional methods to assist the classification, especially in the prenatal setting.
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Affiliation(s)
- Idit Maya
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sarit Kahana
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel
| | - Ifaat Agmon-Fishman
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel
| | - Cochava Klein
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel
| | - Reut Matar
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel
| | - Racheli Berger
- Genetics Laboratory, Maccabi Health Services, Rehovot, Israel
| | | | - Mordechai Shohat
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Genetics Laboratory, Maccabi Health Services, Rehovot, Israel.,Bioinformatics Unit, Sheba Cancer Research Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Daphna Marom
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Genetics Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Lina Basel-Salmon
- Recanati Genetics Institute, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Felsenstein Medical Research Center, Rabin Medical Center, Petah Tikva, Israel
| | - Lena Sagi-Dain
- Genetics Institute, Carmel Medical Center, affiliated to the Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
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