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Ke X, Yang H, Pan H, Jiang Y, Li M, Zhang H, Hao N, Zhu H. The Application of Optical Genome Mapping (OGM) in Severe Short Stature Caused by Duplication of 15q14q21.3. Genes (Basel) 2023; 14:genes14051016. [PMID: 37239376 DOI: 10.3390/genes14051016] [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: 03/28/2023] [Revised: 04/26/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
(1) Background: Optical genome mapping (OGM) is a novel approach to identifying genomic structural variations with high accuracy and resolution. We report a proband with severe short stature caused by 46, XY, der (16) ins (16;15) (q23; q21.3q14) that was detected by OGM combined with other tests and review the clinical features of patients with duplication within 15q14q21.3; (2) Methods: OGM, whole exon sequencing (WES), copy number variation sequencing (CNV-seq), and karyotyping were used; (3) Results: The proband was a 10.7-year-old boy with a complaint of severe short stature (-3.41SDS) and abnormal gait. He had growth hormone deficiency, lumbar lordosis, and epiphyseal dysplasia of both femurs. WES and CNV-seq showed a 17.27 Mb duplication of chromosome 15, and there was an insertion in chromosome 16 found by karyotyping. Furthermore, OGM revealed that duplication of 15q14q21.3 was inversely inserted into 16q23.1, resulting in two fusion genes. A total of fourteen patients carried the duplication of 15q14q21.3, with thirteen previously reported and one from our center, 42.9% of which were de novo. In addition, neurologic symptoms (71.4%,10/14) were the most common phenotypes; (4) Conclusions: OGM combined with other genetic methods can reveal the genetic etiology of patients with the clinical syndrome, presenting great potential for use in properly diagnosing in the genetic cause of the clinical syndrome.
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Affiliation(s)
- Xiaoan Ke
- State Key Laboratory of Complex Severe and Rare Diseases, Chinese Research Center for Behavior Medicine in Growth and Development, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Hongbo Yang
- State Key Laboratory of Complex Severe and Rare Diseases, Chinese Research Center for Behavior Medicine in Growth and Development, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Hui Pan
- State Key Laboratory of Complex Severe and Rare Diseases, Chinese Research Center for Behavior Medicine in Growth and Development, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Yulin Jiang
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric and Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Mengmeng Li
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric and Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Hanzhe Zhang
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric and Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Na Hao
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric and Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Huijuan Zhu
- State Key Laboratory of Complex Severe and Rare Diseases, Chinese Research Center for Behavior Medicine in Growth and Development, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
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Dremsek P, Schwarz T, Weil B, Malashka A, Laccone F, Neesen J. Optical Genome Mapping in Routine Human Genetic Diagnostics-Its Advantages and Limitations. Genes (Basel) 2021; 12:1958. [PMID: 34946907 PMCID: PMC8701374 DOI: 10.3390/genes12121958] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 12/01/2022] Open
Abstract
In recent years, optical genome mapping (OGM) has developed into a highly promising method of detecting large-scale structural variants in human genomes. It is capable of detecting structural variants considered difficult to detect by other current methods. Hence, it promises to be feasible as a first-line diagnostic tool, permitting insight into a new realm of previously unknown variants. However, due to its novelty, little experience with OGM is available to infer best practices for its application or to clarify which features cannot be detected. In this study, we used the Saphyr system (Bionano Genomics, San Diego, CA, USA), to explore its capabilities in human genetic diagnostics. To this end, we tested 14 DNA samples to confirm a total of 14 different structural or numerical chromosomal variants originally detected by other means, namely, deletions, duplications, inversions, trisomies, and a translocation. Overall, 12 variants could be confirmed; one deletion and one inversion could not. The prerequisites for detection of similar variants were explored by reviewing the OGM data of 54 samples analyzed in our laboratory. Limitations, some owing to the novelty of the method and some inherent to it, were described. Finally, we tested the successful application of OGM in routine diagnostics and described some of the challenges that merit consideration when utilizing OGM as a diagnostic tool.
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Affiliation(s)
- Paul Dremsek
- Institute of Medical Genetics, Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria; (T.S.); (B.W.); (A.M.); (F.L.); (J.N.)
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Qu S, Wang L, Cai A, Cui S, Bai N, Liu N, Kong X. Exploring the cause of early miscarriage with SNP-array analysis and karyotyping. J Matern Fetal Neonatal Med 2017; 32:1-10. [PMID: 29034762 DOI: 10.1080/14767058.2017.1367379] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE The aim of this study is to explore the cause of miscarriage, providing risk assessment to guide the next pregnancy. METHODS Four hundred eighty-four products-of-conception (POC) samples were analyzed by single nucleotide polymorphism (SNP) array, and peripheral blood samples of couples were collected for karyotyping or fluorescence in situ hybridization (FISH) analysis. RESULTS Four hundred sixty-eight of the 484 (96.7%) fresh POC samples were successfully analyzed using SNP-array. The rate of clinically significant chromosomal abnormalities were 58.3% (274/468), in which rates of aneuploidy, polyploidy, partial aneuploidy, uniparental isodisomy (isoUPD), and pathogenic microdeletion/microduplication were 43.4% (203/468), 8.8% (41/468), 3.6% (17/468), 1.9% (9/48), and 0.9% (4/468), respectively. The percentage of embryonic chromosomal abnormalities significantly increased with maternal age of patients older than 35 years old. Among 468 couples, 12 major chromosomal rearrangements were detected by G-banding, including nine reciprocal translocations, two Robertsonian translocations, and one superfemale. CONCLUSIONS Chromosome abnormality is the main causes of early miscarriage, and aneuploidies are the most common type of chromosomal abnormalities. Application of SNP array and karyotyping in early miscarriage can provide more genetic information about miscarriage, providing risk assessment to guide the next pregnancy.
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Affiliation(s)
- Suzhen Qu
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Li Wang
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Aojie Cai
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Siying Cui
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Nan Bai
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Ning Liu
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
| | - Xiangdong Kong
- a Center for Genetics and Prenatal Diagnosis , the First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan , China
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Mohan S, Nampoothiri S, Yesodharan D, Venkatesan V, Koshy T, Paul SFD, Perumal V. Reciprocal Microduplication of the Williams-Beuren Syndrome Chromosome Region in a 9-Year-Old Omani Boy. Lab Med 2016; 47:171-5. [PMID: 27069036 DOI: 10.1093/labmed/lmw005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Microdeletions of the 7q11.23 Williams-Beuren syndrome chromosome region (WBSCR) are reported with a frequency of 1 in 10,000, whereas microduplications of the region, although expected to occur at the same frequency, are not widely reported. METHOD We evaluated a 9-year old Omani boy for idiopathic intellectual disability using genetic methods, including multiplex ligation-dependent probe amplification (MLPA), for detection of microdeletions (P064-B3). RESULTS MLPA analysis revealed that the boy has a rare microduplication of the WBSCR. Prominent clinical features include global developmental delay with pronounced speech delay, dysmorphic facies, and autistic features. CONCLUSION Microduplications, in general, are reported at a lesser frequency, perhaps owing to their milder phenotype. Complete genetic assessment in children with idiopathic intellectual disability would help in identifying rare conditions such as duplication of the WBSCR.
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Affiliation(s)
- Shruthi Mohan
- Department of Human Genetics, Sri Ramachandra University, Chennai, India
| | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences & Research Center, Kochi, India
| | - Dhanya Yesodharan
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences & Research Center, Kochi, India
| | | | - Teena Koshy
- Department of Human Genetics, Sri Ramachandra University, Chennai, India
| | - Solomon F D Paul
- Department of Human Genetics, Sri Ramachandra University, Chennai, India
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Mimouni-Bloch A, Yeshaya J, Kahana S, Maya I, Basel-Vanagaite L. A de-novo interstitial microduplication involving 2p16.1-p15 and mirroring 2p16.1-p15 microdeletion syndrome: Clinical and molecular analysis. Eur J Paediatr Neurol 2015; 19:711-5. [PMID: 26278498 DOI: 10.1016/j.ejpn.2015.07.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 06/13/2015] [Accepted: 07/20/2015] [Indexed: 01/15/2023]
Abstract
BACKGROUND Microdeletions of various sizes in the 2p16.1-p15 chromosomal region have been grouped together under the 2p16.1-p15 microdeletion syndrome. Children with this syndrome generally share certain features including microcephaly, developmental delay, facial dysmorphism, urogenital and skeletal abnormalities. We present a child with a de-novo interstitial 1665 kb duplication of 2p16.1-p15. METHODS AND RESULTS Clinical features of this child are distinct from those of children with the 2p16.1-p15 microdeletion syndrome, specifically the head circumference which is within the normal range and mild intellectual disability with absence of autistic behaviors. Microduplications many times bear milder clinical phenotypes in comparison with corresponding microdeletion syndromes. Indeed, as compared to the microdeletion syndrome patients, the 2p16.1-p15 microduplication seems to have a milder cognitive effect and no effect on other body systems. Limited information available in genetic databases about cases with overlapping duplications indicates that they all have abnormal developmental phenotypes. CONCLUSION The involvement of genes in this location including BCL11A, USP34 and PEX13, affecting fundamental developmental processes both within and outside the nervous system may explain the clinical features of the individual described in this report.
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Affiliation(s)
- Aviva Mimouni-Bloch
- The Pediatric Neurology and Developmental Unit, Loewenstein Rehabilitation Hospital 278 Ahuza Street, Raanana, 43100, Israel; Sackler Faculty of Medicine, Tel-Aviv University, P.O. 39040, Ramat-Aviv, Tel-Aviv, 69978, Israel.
| | - Josepha Yeshaya
- Raphael Recanati Genetic Institute, Rabin Medical Center Beilinson Campus and Schneider Children's Medical Center of Israel, Derech Ze'ev Jabotinsky 39, Petah Tikva, 4941492, Israel.
| | - Sarit Kahana
- Raphael Recanati Genetic Institute, Rabin Medical Center Beilinson Campus and Schneider Children's Medical Center of Israel, Derech Ze'ev Jabotinsky 39, Petah Tikva, 4941492, Israel.
| | - Idit Maya
- Raphael Recanati Genetic Institute, Rabin Medical Center Beilinson Campus and Schneider Children's Medical Center of Israel, Derech Ze'ev Jabotinsky 39, Petah Tikva, 4941492, Israel.
| | - Lina Basel-Vanagaite
- Sackler Faculty of Medicine, Tel-Aviv University, P.O. 39040, Ramat-Aviv, Tel-Aviv, 69978, Israel; Raphael Recanati Genetic Institute, Rabin Medical Center Beilinson Campus and Schneider Children's Medical Center of Israel, Derech Ze'ev Jabotinsky 39, Petah Tikva, 4941492, Israel; Felsenstein Medical Research Center, Rabin Medical Center, Derech Ze'ev Jabotinsky 39, Petah Tikva, 4941492, Israel.
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6
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Abstract
Copy number variations (CNVs) are structural variations of the human genome. These alterations result in variant copy numbers of certain stretches of DNA. In other words, some regions may be present in more or less copies than in a reference genome; however, these copy number changes do not have any impact on the phenotype. Also, CNVs may be extremely large and cytogenetically detectable or submicroscopic but still spanning several megabasepairs (Mb). In the recent years, array technology has identified especially the latter ones as so-called copy number variant (CNV) polymorphisms. These CNVs are detected in ~12 % of the human genome sequences and may comprise several hundred kilobasepairs. CNVs contribute significantly to the inter-individual differences in humans, and can range between 0.5 and 1.5 Mb amongst different genomes, well within the level of detection using cytogenetics techniques. Thus, they can be visualized by FISH using bacterial artificial chromosomes (BACs) as probes. Here we describe a method that enables discrimination of individual homologous chromosomes at the single cell level based on CNVs in the genome, called parental origin determination fluorescence in situ hybridization (POD-FISH). Possible fields of applications of this single cell-directed approach are in analyses of the parental origin of single chromosomes in inherited and acquired chromosomal aberrations.
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Escaramís G, Docampo E, Rabionet R. A decade of structural variants: description, history and methods to detect structural variation. Brief Funct Genomics 2015; 14:305-14. [PMID: 25877305 DOI: 10.1093/bfgp/elv014] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
In the past decade, the view on genomic structural variation (SV) has been changed completely. SVs, previously considered rare events, are now recognized as the largest source of interindividual genetic variation affecting more bases than single nucleotide polymorphisms, variable number of tandem repeats and other small genetic variants. They have also been shown to play a role in phenotypic variation and in disease. In this review, the authors will provide an introduction to SV; a short historical perspective on the research of this source of genomic variation; a description of the types of structural variants, and on how they may have arisen; and an overview on methods of detecting structural variants, focusing on the analysis of high-throughput sequencing data.
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Wen J, Hanna CW, Martell S, Leung PC, Lewis SM, Robinson WP, Stephenson MD, Rajcan-Separovic E. Functional consequences of copy number variants in miscarriage. Mol Cytogenet 2015; 8:6. [PMID: 25674159 PMCID: PMC4324423 DOI: 10.1186/s13039-015-0109-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 01/09/2015] [Indexed: 02/01/2023] Open
Abstract
Background The presence of unique copy number variations (CNVs) in miscarriages suggests that their integral genes have a role in maintaining early pregnancy. In our previous work, we identified 19 unique CNVs in ~40% of studied euploid miscarriages, which were predominantly familial in origin. In our current work, we assessed their relevance to miscarriage by expression analysis of 14 genes integral to CNVs in available miscarriage chorionic villi. As familial CNVs could cause miscarriage due to imprinting effect, we investigated the allelic expression of one of the genes (TIMP2) previously suggested to be maternally expressed in placenta and involved in placental remodelling and embryo development. Results Six out of fourteen genes had detectable expression in villi and for three genes the RNA and protein expression was altered due to maternal CNVs. These genes were integral to duplication on Xp22.2 (TRAPPC2 and OFD1) or disrupted by a duplication mapping to 17q25.3 (TIMP2). RNA and protein expression was increased for TRAPPC2 and OFD1 and reduced for TIMP2 in carrier miscarriages. The three genes have roles in processes important for pregnancy development such as extracellular matrix homeostasis (TIMP2 and TRAPPC2) and cilia function (OFD1). TIMP2 allelic expression was not affected by the CNV in miscarriages in comparison to control elective terminations. Conclusion We propose that functional studies of CNVs could help determine if and how the miscarriage CNVs affect the expression of integral genes. In case of parental CNVs, assessment of the function of their integral genes in parental reproductive tissues should be also considered in the future, especially if they affect processes relevant for pregnancy development and support. Electronic supplementary material The online version of this article (doi:10.1186/s13039-015-0109-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiadi Wen
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, V6T 2B5 Canada.,Child & Family Research Institute, Vancouver, V5Z 4H4 Canada
| | - Courtney W Hanna
- Child & Family Research Institute, Vancouver, V5Z 4H4 Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, V6T 1Z3 Canada
| | - Sally Martell
- Child & Family Research Institute, Vancouver, V5Z 4H4 Canada
| | - Peter Ck Leung
- Child & Family Research Institute, Vancouver, V5Z 4H4 Canada.,Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, V6Z 2 K5 Canada
| | - Suzanne Me Lewis
- Department of Medical Genetics, University of British Columbia, Vancouver, V6T 1Z3 Canada
| | - Wendy P Robinson
- Child & Family Research Institute, Vancouver, V5Z 4H4 Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, V6T 1Z3 Canada
| | - Mary D Stephenson
- Department of Obstetrics and Gynecology, University of Illinois at Chicago, Chicago, 60612 USA
| | - Evica Rajcan-Separovic
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, V6T 2B5 Canada.,Child & Family Research Institute, Vancouver, V5Z 4H4 Canada
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10
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Gancheva K, Postadjian A, Brazma D, Grace C, Chanalaris A, Nacheva E, Apostolova M. Copy Number Variants: Distribution in Patients with Coronary Atherosclerosis. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2009.10817620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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11
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Qiao Y, Badduke C, Mercier E, Lewis SME, Pavlidis P, Rajcan-Separovic E. miRNA and miRNA target genes in copy number variations occurring in individuals with intellectual disability. BMC Genomics 2013; 14:544. [PMID: 23937676 PMCID: PMC3750877 DOI: 10.1186/1471-2164-14-544] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Accepted: 08/06/2013] [Indexed: 12/20/2022] Open
Abstract
Background MicroRNAs (miRNAs) are a family of short, non-coding RNAs modulating expression of human protein coding genes (miRNA target genes). Their dysfunction is associated with many human diseases, including neurodevelopmental disorders. It has been recently shown that genomic copy number variations (CNVs) can cause aberrant expression of integral miRNAs and their target genes, and contribute to intellectual disability (ID). Results To better understand the CNV-miRNA relationship in ID, we investigated the prevalence and function of miRNAs and miRNA target genes in five groups of CNVs. Three groups of CNVs were from 213 probands with ID (24 de novo CNVs, 46 familial and 216 common CNVs), one group of CNVs was from a cohort of 32 cognitively normal subjects (67 CNVs) and one group of CNVs represented 40 ID related syndromic regions listed in DECIPHER (30 CNVs) which served as positive controls for CNVs causing or predisposing to ID. Our results show that 1). The number of miRNAs is significantly higher in de novo or DECIPHER CNVs than in familial or common CNV subgroups (P < 0.01). 2). miRNAs with brain related functions are more prevalent in de novo CNV groups compared to common CNV groups. 3). More miRNA target genes are found in de novo, familial and DECIPHER CNVs than in the common CNV subgroup (P < 0.05). 4). The MAPK signaling cascade is found to be enriched among the miRNA target genes from de novo and DECIPHER CNV subgroups. Conclusions Our findings reveal an increase in miRNA and miRNA target gene content in de novo versus common CNVs in subjects with ID. Their expression profile and participation in pathways support a possible role of miRNA copy number change in cognition and/or CNV-mediated developmental delay. Systematic analysis of expression/function of miRNAs in addition to coding genes integral to CNVs could uncover new causes of ID.
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Affiliation(s)
- Ying Qiao
- Department of Pathology and Lab Medicine, BC Child and Family Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
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Wang P, Carrion P, Qiao Y, Tyson C, Hrynchak M, Calli K, Lopez-Rangel E, Andrieux J, Delobel B, Duban-Bedu B, Thuresson AC, Annerén G, Liu X, Rajcan-Separovic E, Suzanne Lewis ME. Genotype-phenotype analysis of 18q12.1-q12.2 copy number variation in autism. Eur J Med Genet 2013; 56:420-5. [PMID: 23727450 DOI: 10.1016/j.ejmg.2013.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/14/2013] [Indexed: 01/18/2023]
Abstract
Autism Spectrum Disorders (ASD) are complex neurodevelopmental conditions characterized by delays in social interactions and communication as well as displays of restrictive/repetitive interests. DNA copy number variants have been identified as a genomic susceptibility factor in ASDs and imply significant genetic heterogeneity. We report a 7-year-old female with ADOS-G and ADI-R confirmed autistic disorder harbouring a de novo 4 Mb duplication (18q12.1). Our subject displays severely deficient expressive language, stereotypic and repetitive behaviours, mild intellectual disability (ID), focal epilepsy, short stature and absence of significant dysmorphic features. Search of the PubMed literature and DECIPHER database identified 4 additional cases involving 18q12.1 associated with autism and/or ID that overlap our case: one duplication, two deletions and one balanced translocation. Notably, autism and ID are seen with genomic gain or loss at 18q12.1, plus epilepsy and short stature in duplication cases, and hypotonia and tall stature in deletion cases. No consistent dysmorphic features were noted amongst the reviewed cases. We review prospective ASD/ID candidate genes integral to 18q12.1, including those coding for the desmocollin/desmoglein cluster, ring finger proteins 125 and 138, trafficking protein particle complex 8 and dystrobrevin-alpha. The collective clinical and molecular features common to microduplication 18q12.1 suggest that dosage-sensitive, position or contiguous gene effects may be associated in the etiopathogenesis of this autism-ID-epilepsy syndrome.
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Affiliation(s)
- Peter Wang
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
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Yamamoto T, Matsuo M, Shimada S, Sangu N, Shimojima K, Aso S, Saito K. De novo triplication of 11q12.3 in a patient with developmental delay and distinctive facial features. Mol Cytogenet 2013; 6:15. [PMID: 23552394 PMCID: PMC3626894 DOI: 10.1186/1755-8166-6-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 03/01/2013] [Indexed: 01/08/2023] Open
Abstract
Background Triplication is a rare chromosomal anomaly. We identified a de novo triplication of 11q12.3 in a patient with developmental delay, distinctive facial features, and others. In the present study, we discuss the mechanism of triplications that are not embedded within duplications and potential genes which may contribute to the phenotype. Results The identified triplication of 11q12.3 was 557 kb long and not embedded within the duplicated regions. The aberrant region was overlapped with the segment reported to be duplicated in 2 other patients. The common phenotypic features in the present patient and the previously reported patient were brain developmental delay, finger abnormalities (including arachnodactuly, camptodactyly, brachydactyly, clinodactyly, and broad thumbs), and preauricular pits. Conclusions Triplications that are not embedded within duplicated regions are rare and sometimes observed as the consequence of non-allelic homologous recombination. The de novo triplication identified in the present study is novel and not embedded within the duplicated region. In the 11q12.3 region, many copy number variations were observed in the database. This may be the trigger of this rare triplication. Because the shortest region of overlap contained 2 candidate genes, STX5 and CHRM1, which show some relevance to neuronal functions, we believe that the genomic copy number gains of these genes may be responsible for the neurological features seen in these patients.
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Affiliation(s)
- Toshiyuki Yamamoto
- Tokyo Women's Medical University Institute for Integrated Medical Sciences, 8-1 Kawada-cho, Shinjuku-ward, Tokyo, 162-8666, Japan.
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Willemsen MH, de Leeuw N, de Brouwer AP, Pfundt R, Hehir-Kwa JY, Yntema HG, Nillesen WM, de Vries BB, van Bokhoven H, Kleefstra T. Interpretation of clinical relevance of X-chromosome copy number variations identified in a large cohort of individuals with cognitive disorders and/or congenital anomalies. Eur J Med Genet 2012; 55:586-98. [DOI: 10.1016/j.ejmg.2012.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 05/05/2012] [Accepted: 05/05/2012] [Indexed: 01/01/2023]
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Grayton HM, Fernandes C, Rujescu D, Collier DA. Copy number variations in neurodevelopmental disorders. Prog Neurobiol 2012; 99:81-91. [DOI: 10.1016/j.pneurobio.2012.07.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 07/20/2011] [Accepted: 07/09/2012] [Indexed: 10/28/2022]
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Baudhuin LM, Donato LJ, Uphoff TS. How novel molecular diagnostic technologies and biomarkers are revolutionizing genetic testing and patient care. Expert Rev Mol Diagn 2012; 12:25-37. [PMID: 22133117 DOI: 10.1586/erm.11.85] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Technological applications and novel biomarkers in the field of molecular diagnostics have never been evolving at a more rapid pace. These novel applications have the promise to change the face of clinical care as we move into the era of personalized medicine. While some of these technologies and biomarkers have been adopted by some clinical laboratories, most laboratories face a steep learning curve in bringing these dramatically new and different molecular diagnostic applications on board. Furthermore, interpreting the vast amounts and new types of data produced by these novel applications brings forth challenges for laboratorians and clinicians alike. In this article, we discuss how some of these emerging novel molecular diagnostic technologies and analytes, such as next-generation sequencing, chromosomal microarray, microRNAs and circulating fetal nucleic acids are revolutionizing patient care and personalized medicine.
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Affiliation(s)
- Linnea M Baudhuin
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA.
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Lundvall M, Rajaei S, Erlandson A, Kyllerman M. Aetiology of severe mental retardation and further genetic analysis by high-resolution microarray in a population-based series of 6- to 17-year-old children. Acta Paediatr 2012; 101:85-91. [PMID: 21767312 DOI: 10.1111/j.1651-2227.2011.02417.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM To investigate the prevalence, co-morbidities and aetiologies of severe mental retardation (SMR) in a cohort of Swedish children and to further penetrate aetiologies in the group with undetermined causes by application of updated clinical-genetic methods. METHODS The study was population-based and included children living in the County of Halland in western Sweden in 2004 (born 1987-1998; 46,000 children). Patients were identified through habilitation centres, paediatric clinics and school health services. Patients with unclear prenatal aetiology were investigated with single nucleotide polymorphism (SNP)-array. RESULTS Severe mental retardation was identified in 133 children from 132 families, corresponding to a prevalence of 2.9 per 1000 children. There were more males than females (90:43).The aetiology was prenatal in 82 (62%), perinatal in 14 (10%) and postnatal in 8 (6%). In 29 (22 %) children, mainly males with autism, the cause could not be related to the time of birth. In the prenatal group, genetic causes dominated, but still 23 children remained undiagnosed; in 5/19 of these patients, a diagnosis could be made after SNP-array analysis. One or more associated neurological handicaps were found in more than half of the children. CONCLUSION Prevalence and co-morbidity were similar to previous Scandinavian studies. High-resolution chromosomal micro-array techniques are valuable diagnostic tools, reducing the number of patients with unexplained SMR.
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Affiliation(s)
- Mikael Lundvall
- Department of Paediatrics, Halland County Hospital, Halmstad, Sweden.
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18
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Abstract
The genetic causes of mental retardation are highly heterogeneous and for a large proportion unknown. Mutations as well as large chromosomal abnormalities are known to contribute to mental retardation, and recently more subtle structural genomic variations have been shown to contribute significantly to this common and complex disorder. Genomic microarrays with increasing resolution levels have revealed the presence of rare de novo CNVs in approximately 15% of all mentally retarded patients. Microarray-based CNV screening is rapidly replacing conventional karyotyping in the diagnostic workflow, resulting in an increased diagnostic yield as well as biological insight into this disorder. In this chapter, an overview is given of the detection and interpretation of copy number variations in mental retardation, with a focus on diagnostic applications. In addition, a detailed protocol is provided for the diagnostic interpretation of copy-number variations in mental retardation.
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Affiliation(s)
- Rolph Pfundt
- Department of Human Genetics, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Liu X, Malenfant P, Reesor C, Lee A, Hudson ML, Harvard C, Qiao Y, Persico AM, Cohen IL, Chudley AE, Forster-Gibson C, Rajcan-Separovic E, Lewis MES, Holden JJA. 2p15-p16.1 microdeletion syndrome: molecular characterization and association of the OTX1 and XPO1 genes with autism spectrum disorders. Eur J Hum Genet 2011; 19:1264-70. [PMID: 21750575 PMCID: PMC3230356 DOI: 10.1038/ejhg.2011.112] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 04/27/2011] [Accepted: 04/29/2011] [Indexed: 12/23/2022] Open
Abstract
Reports of unrelated individuals with autism spectrum disorder (ASD) and similar clinical features having overlapping de novo interstitial deletions at 2p15-p16.1 suggest that this region harbors a gene(s) important to the development of autism. We molecularly characterized two such deletions, selecting two genes in this region, exportin 1 (XPO1) and orthodenticle homolog 1 (OTX1) for association studies in three North American cohorts (Autism Spectrum Disorder - Canadian American Research Consortium (ASD-CARC), New York, and Autism Genetic Resource Exchange (AGRE)) and one Italian cohort (Società Italiana per la Ricerca e la Formazione sull'Autismo (SIRFA)) of families with ASD. In XPO1, rs6735330 was associated with autism in all four cohorts (P<0.05), being significant in ASD-CARC cohorts (P-value following false discovery rate correction for multiple testing (P(FDR))=1.29 × 10(-5)), the AGRE cohort (P(FDR)=0.0011) and the combined families (P(FDR)=2.34 × 10(-9)). Similarly, in OTX1, rs2018650 and rs13000344 were associated with autism in ASD-CARC cohorts (P(FDR)=8.65 × 10(-7) and 6.07 × 10(5), respectively), AGRE cohort (P(FDR)=0.0034 and 0.015, respectively) and the combined families (P(FDR)=2.34 × 10(-9) and 0.00017, respectively); associations were marginal or insignificant in the New York and SIRFA cohorts. A significant association (P(FDR)=2.63 × 10(-11)) was found for the rs2018650G-rs13000344C haplotype. The above three SNPs were associated with severity of social interaction and verbal communication deficits and repetitive behaviors (P-values <0.01). No additional deletions were identified following screening of 798 ASD individuals. Our results indicate that deletion 2p15-p16.1 is not commonly associated with idiopathic ASD, but represents a novel contiguous gene syndrome associated with a constellation of phenotypic features (autism, intellectual disability, craniofacial/CNS dysmorphology), and that XPO1 and OXT1 may contribute to ASD in 2p15-p16.1 deletion cases and non-deletion cases of ASD mapping to this chromosome region.
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Affiliation(s)
- Xudong Liu
- Department of Psychiatry, Queen's University, Kingston, Ontario, Canada
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
| | - Patrick Malenfant
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Physiology, Queen's University, Kingston, Ontario, Canada
| | - Chelsea Reesor
- Department of Psychiatry, Queen's University, Kingston, Ontario, Canada
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
| | - Alana Lee
- Department of Psychiatry, Queen's University, Kingston, Ontario, Canada
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
| | - Melissa L Hudson
- Department of Psychiatry, Queen's University, Kingston, Ontario, Canada
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
| | - Chansonette Harvard
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ying Qiao
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia and BC Child and Family Research Institute, Vancouver, British Columbia, Canada
| | - Antonio M Persico
- Department of Child and Adolescent Psychiatry, Laboratory of Molecular Psychiatry and Neurogenetics, University Campus Bio-Medico, Rome, Italy
- Department of Experimental Neurosciences, IRCCS ‘Fondazione Santa Lucia', Rome, Italy
| | - Ira L Cohen
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Psychology and George A. Jervis Clinic, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Albert E Chudley
- Autism Spectrum Disorders – Canadian-American Research Consortium
- WRHA Program in Genetics & Metabolism, Departments of Pediatrics and Child Health, Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Cynthia Forster-Gibson
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Family Medicine, Queen's University, Kingston, Ontario, Canada
| | - Evica Rajcan-Separovic
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - ME Suzanne Lewis
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Medical Genetics, University of British Columbia and BC Child and Family Research Institute, Vancouver, British Columbia, Canada
| | - Jeanette JA Holden
- Department of Psychiatry, Queen's University, Kingston, Ontario, Canada
- Autism Research Program and Genetics and Genomics Research Laboratory, Ongwanada Resource Centre, Kingston, Ontario, Canada
- Autism Spectrum Disorders – Canadian-American Research Consortium
- Department of Physiology, Queen's University, Kingston, Ontario, Canada
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
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20
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Malenfant P, Liu X, Hudson ML, Qiao Y, Hrynchak M, Riendeau N, Hildebrand MJ, Cohen IL, Chudley AE, Forster-Gibson C, Mickelson ECR, Rajcan-Separovic E, Lewis MES, Holden JJA. Association of GTF2i in the Williams-Beuren Syndrome Critical Region with Autism Spectrum Disorders. J Autism Dev Disord 2011; 42:1459-69. [DOI: 10.1007/s10803-011-1389-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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21
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Hochstenbach R, Buizer-Voskamp JE, Vorstman JAS, Ophoff RA. Genome arrays for the detection of copy number variations in idiopathic mental retardation, idiopathic generalized epilepsy and neuropsychiatric disorders: lessons for diagnostic workflow and research. Cytogenet Genome Res 2011; 135:174-202. [PMID: 22056632 DOI: 10.1159/000332928] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022] Open
Abstract
We review the contributions and limitations of genome-wide array-based identification of copy number variants (CNVs) in the clinical diagnostic evaluation of patients with mental retardation (MR) and other brain-related disorders. In unselected MR referrals a causative genomic gain or loss is detected in 14-18% of cases. Usually, such CNVs arise de novo, are not found in healthy subjects, and have a major impact on the phenotype by altering the dosage of multiple genes. This high diagnostic yield justifies array-based segmental aneuploidy screening as the initial genetic test in these patients. This also pertains to patients with autism (expected yield about 5-10% in nonsyndromic and 10-20% in syndromic patients) and schizophrenia (at least 5% yield). CNV studies in idiopathic generalized epilepsy, attention-deficit hyperactivity disorder, major depressive disorder and Tourette syndrome indicate that patients have, on average, a larger CNV burden as compared to controls. Collectively, the CNV studies suggest that a wide spectrum of disease-susceptibility variants exists, most of which are rare (<0.1%) and of variable and usually small effect. Notwithstanding, a rare CNV can have a major impact on the phenotype. Exome sequencing in MR and autism patients revealed de novo mutations in protein coding genes in 60 and 20% of cases, respectively. Therefore, it is likely that arrays will be supplanted by next-generation sequencing methods as the initial and perhaps ultimate diagnostic tool in patients with brain-related disorders, revealing both CNVs and mutations in a single test.
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Affiliation(s)
- R Hochstenbach
- Division of Biomedical Genetics, Department of Medical Genetics, University Medical Centre Utrecht, Utrecht, The Netherlands.
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22
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Prontera P, Bernardini L, Stangoni G, Capalbo A, Rogaia D, Romani R, Ardisia C, Dallapiccola B, Donti E. Deletion 2p15-16.1 syndrome: case report and review. Am J Med Genet A 2011; 155A:2473-8. [PMID: 21910216 DOI: 10.1002/ajmg.a.33875] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 11/22/2010] [Indexed: 01/19/2023]
Abstract
We report on a 9-year-old female patient with facial anomalies and developmental delay, heterozygous for three de novo rearrangements: a paracentric inversion of chromosome 7, an apparently balanced translocation between chromosome 1 and 7, involving the same inverted chromosome 7, detected by standard cytogenetic analysis [46,XX, der(7) inv(7)(q21.1q32.1)t(1;7)(q23q32.1)]; and a 2p16.1 deletion, spanning about 3.5 Mb of genomic DNA, shown by SNP-array analysis [arr 2p16.1 (56,706,666-60,234,485)x1 dn]. Clinical features and cytogenetic imbalance in our patient were similar to those reported in five published cases, suggesting that this genomic region is prone to recombination and its hemizygosity results in a distinct although variable spectrum of clinical manifestations.
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Affiliation(s)
- Paolo Prontera
- Sezione di Genetica Medica, Università e Azienda Ospedaliera di Perugia, Italy
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23
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Lehalle D, Williams C, Siu VM, Clayton-Smith J. Fetal pads as a clue to the diagnosis of Pitt-Hopkins syndrome. Am J Med Genet A 2011; 155A:1685-9. [PMID: 21671383 DOI: 10.1002/ajmg.a.34055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 03/25/2011] [Indexed: 01/22/2023]
Abstract
Pitt-Hopkins syndrome (PHS) is characterized by severe mental retardation, characteristic facial features including a wide mouth and intermittent overbreathing. It is due to abnormalities of the TCF4 gene at 18q21.1 and over 50 cases have now been reported in the literature. The clinical features overlap significantly with those of Angelman, Rett, and Mowat-Wilson syndromes. We have observed prominent fetal pads as a feature in several individuals with PHS and suggested that this is a useful clinical sign which helps to distinguish PHS from other conditions in the differential diagnosis and may guide genetic testing.
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Affiliation(s)
- Daphne Lehalle
- Manchester Biomedical Research Centre, MAHSC, St Mary's Hospital, UK.
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24
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Vacic V, McCarthy S, Malhotra D, Murray F, Chou HH, Peoples A, Makarov V, Yoon S, Bhandari A, Corominas R, Iakoucheva LM, Krastoshevsky O, Krause V, Larach-Walters V, Welsh DK, Craig D, Kelsoe JR, Gershon ES, Leal SM, Aquila MD, Morris DW, Gill M, Corvin A, Insel PA, McClellan J, King MC, Karayiorgou M, Levy DL, DeLisi LE, Sebat J. Duplications of the neuropeptide receptor gene VIPR2 confer significant risk for schizophrenia. Nature 2011; 471:499-503. [PMID: 21346763 PMCID: PMC3351382 DOI: 10.1038/nature09884] [Citation(s) in RCA: 256] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 01/28/2011] [Indexed: 01/19/2023]
Abstract
Rare copy number variants (CNVs) have a prominent role in the aetiology of schizophrenia and other neuropsychiatric disorders. Substantial risk for schizophrenia is conferred by large (>500-kilobase) CNVs at several loci, including microdeletions at 1q21.1 (ref. 2), 3q29 (ref. 3), 15q13.3 (ref. 2) and 22q11.2 (ref. 4) and microduplication at 16p11.2 (ref. 5). However, these CNVs collectively account for a small fraction (2-4%) of cases, and the relevant genes and neurobiological mechanisms are not well understood. Here we performed a large two-stage genome-wide scan of rare CNVs and report the significant association of copy number gains at chromosome 7q36.3 with schizophrenia. Microduplications with variable breakpoints occurred within a 362-kilobase region and were detected in 29 of 8,290 (0.35%) patients versus 2 of 7,431 (0.03%) controls in the combined sample. All duplications overlapped or were located within 89 kilobases upstream of the vasoactive intestinal peptide receptor gene VIPR2. VIPR2 transcription and cyclic-AMP signalling were significantly increased in cultured lymphocytes from patients with microduplications of 7q36.3. These findings implicate altered vasoactive intestinal peptide signalling in the pathogenesis of schizophrenia and indicate the VPAC2 receptor as a potential target for the development of new antipsychotic drugs.
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Affiliation(s)
- Vladimir Vacic
- Stanley Center for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 12824
- Department of Computer Science, Columbia University, New York, NY 10027
| | - Shane McCarthy
- Stanley Center for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 12824
| | - Dheeraj Malhotra
- Beyster Center for Genomics of Psychiatric Diseases, University of California, San Diego, La Jolla, CA 1020103
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
- Stanley Center for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 12824
| | - Fiona Murray
- Department of Medicine University of California, San Diego, La Jolla, CA 1020103
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 1020103; Veterans Affairs San Diego Healthcare System, San Diego, CA 92161
| | - Hsun-Hua Chou
- Beyster Center for Genomics of Psychiatric Diseases, University of California, San Diego, La Jolla, CA 1020103
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
| | - Aine Peoples
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Dept. of Psychiatry, Trinity College Dublin, Ireland
| | - Vladimir Makarov
- Seaver Autism Center Mount Sinai School of Medicine, New York, New York 10029
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029
| | - Seungtai Yoon
- Seaver Autism Center Mount Sinai School of Medicine, New York, New York 10029
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029
| | - Abhishek Bhandari
- Beyster Center for Genomics of Psychiatric Diseases, University of California, San Diego, La Jolla, CA 1020103
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
- Stanley Center for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 12824
| | - Roser Corominas
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
| | - Lilia M. Iakoucheva
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
| | | | | | | | - David K. Welsh
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
- Center for Chronobiology, University of California, San Diego, La Jolla, CA 1020103
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 1020103; Veterans Affairs San Diego Healthcare System, San Diego, CA 92161
| | - David Craig
- Neurogenomics Division, Translational Genomics Research Institute, Phoenix, Arizona 85004
| | - John R. Kelsoe
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 1020103
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 1020103; Veterans Affairs San Diego Healthcare System, San Diego, CA 92161
| | - Elliot S. Gershon
- Department of Psychiatry and Behavioral Neuroscience, The University of Chicago, Chicago, IL 60637
| | - Suzanne M. Leal
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77025
| | - Marie Dell Aquila
- Division of Medical Genetics, University of California, San Diego, La Jolla, CA 1020103
- Department of Medicine University of California, San Diego, La Jolla, CA 1020103
| | - Derek W. Morris
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Dept. of Psychiatry, Trinity College Dublin, Ireland
| | - Michael Gill
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Dept. of Psychiatry, Trinity College Dublin, Ireland
| | - Aiden Corvin
- Neuropsychiatric Genetics Research Group, Institute of Molecular Medicine and Dept. of Psychiatry, Trinity College Dublin, Ireland
| | - Paul A. Insel
- Department of Medicine University of California, San Diego, La Jolla, CA 1020103
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 1020103; Veterans Affairs San Diego Healthcare System, San Diego, CA 92161
| | - Jon McClellan
- Department of Psychiatry, University of Washington, Seattle WA 98195
| | - Mary-Claire King
- Department of Genome Sciences University of Washington, Seattle WA 98195
- Department of Medicine, University of Washington, Seattle WA 98195
| | | | | | - Lynn E. DeLisi
- Department of Psychiatry, Boston VA Healthcare System and Harvard Medical School, Brockton, MA 02301
| | - Jonathan Sebat
- Beyster Center for Genomics of Psychiatric Diseases, University of California, San Diego, La Jolla, CA 1020103
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 1020103
- Department of Cellular Molecular and Molecular Medicine University of California, San Diego, La Jolla, CA 1020103
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 1020103
- Stanley Center for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 12824
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Peeters B, Benninga MA, Hennekam RC. Childhood constipation; an overview of genetic studies and associated syndromes. Best Pract Res Clin Gastroenterol 2011; 25:73-88. [PMID: 21382580 DOI: 10.1016/j.bpg.2010.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/03/2010] [Accepted: 12/13/2010] [Indexed: 01/31/2023]
Abstract
Constipation is a common problem in children but little is known about its exact pathophysiology. Environmental, behavioural but also genetic factors are thought to play a role in the aetiology of childhood constipation. We provide an overview of genetic studies performed in constipation. Until now, linkage studies, association studies and direct gene sequencing have failed to identify mutations in specific genes associated with constipation. We show that along with functional constipation, there are numerous clinical syndromes associated with childhood constipation. These syndromic forms of constipation appear to be the result of mutations in genes affecting all aspects of the normal physiology of human defecation. We stress that syndromic causes of childhood constipation should be considered in the evaluation of a constipated child.
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Affiliation(s)
- B Peeters
- Department of Paediatric Gastrointestinal Motility and Nutrition, Emma Children's Hospital, Academic Medical Centre, Amsterdam, The Netherlands.
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Abstract
BACKGROUND For many years, the prevailing paradigm has stated that in each individual with schizophrenia (SZ) the genetic risk is due to a combination of many genetic variants, individually of small effect. Recent empirical data are prompting a re-evaluation of this polygenic, common disease-common variant (CDCV) model. Evidence includes a lack of the expected strong positive findings from genome-wide association studies and the concurrent discovery of many different mutations that individually strongly predispose to SZ and other psychiatric disorders. This has led some to adopt a mixed model wherein some cases are caused by polygenic mechanisms and some by single mutations. This model runs counter to a substantial body of theoretical literature that had supposedly conclusively rejected Mendelian inheritance with genetic heterogeneity. Here we ask how this discrepancy between theory and data arose and propose a rationalization of the recent evidence base. METHOD In light of recent empirical findings, we reconsider the methods and conclusions of early theoretical analyses and the explicit assumptions underlying them. RESULTS We show that many of these assumptions can now be seen to be false and that the model of genetic heterogeneity is consistent with observed familial recurrence risks, endophenotype studies and other population-wide parameters. CONCLUSIONS We argue for a more biologically consilient mixed model that involves interactions between disease-causing and disease-modifying variants in each individual. We consider the implications of this model for moving SZ research beyond statistical associations to pathogenic mechanisms.
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Affiliation(s)
- K J Mitchell
- Smurfit Institute of Genetics, Trinity College Dublin, Ireland.
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27
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Manning M, Hudgins L. Array-based technology and recommendations for utilization in medical genetics practice for detection of chromosomal abnormalities. Genet Med 2010; 12:742-5. [PMID: 20962661 PMCID: PMC3111046 DOI: 10.1097/gim.0b013e3181f8baad] [Citation(s) in RCA: 403] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Laboratory evaluation of patients with developmental delay/intellectual disability, congenital anomalies, and dysmorphic features has changed significantly in the last several years with the introduction of microarray technologies. Using these techniques, a patient's genome can be examined for gains or losses of genetic material too small to be detected by standard G-banded chromosome studies. This increased resolution of microarray technology over conventional cytogenetic analysis allows for identification of chromosomal imbalances with greater precision, accuracy, and technical sensitivity. A variety of array-based platforms are now available for use in clinical practice, and utilization strategies are evolving. Thus, a review of the utility and limitations of these techniques and recommendations regarding present and future application in the clinical setting are presented in this study.
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Affiliation(s)
- Melanie Manning
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA.
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28
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Rajcan-Separovic E, Diego-Alvarez D, Robinson WP, Tyson C, Qiao Y, Harvard C, Fawcett C, Kalousek D, Philipp T, Somerville MJ, Stephenson MD. Identification of copy number variants in miscarriages from couples with idiopathic recurrent pregnancy loss. Hum Reprod 2010; 25:2913-22. [PMID: 20847186 DOI: 10.1093/humrep/deq202] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Recurrent pregnancy loss (RPL), defined as two or more miscarriages, affects 3-5% of couples trying to establish a family. Despite extensive evaluation, no factor is identified in ∼40% of cases. In this study, we investigated the possibility that submicroscopic chromosomal changes, not detectable by conventional cytogenetic analysis, exist in miscarriages with normal karyotypes (46,XY or 46,XX) from couples with idiopathic RPL. METHODS Array comparative genomic hybridization (array-CGH) was used to assess for DNA copy number variants (CNVs) in 26 miscarriages with normal karyotypes. Parental array-CGH analysis was performed to determine if miscarriage CNVs were de novo or inherited. RESULTS There were 11 unique (previously not described) CNVs, all inherited, identified in 13 miscarriages from 8 couples. The maternal origin of two CNVs was of interest as they involved the imprinted genes TIMP2 and CTNNA3, which are only normally expressed from the maternal copy in the placenta. Two additional cohorts, consisting of 282 women with recurrent miscarriage (RM) and 61 fertile women, were screened for these two CNVs using a Quantitative Multiplex Fluorescent PCR of Short Fragments assay. One woman with RM, but none of the fertile women, carried the CTNNA3-associated CNV. CONCLUSIONS This preliminary study shows that array-CGH is useful for detecting CNVs in cases of RPL. Further investigations of CNVs, particularly those involving genes that are imprinted in placenta, in women with RPL could be worthwhile.
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Affiliation(s)
- E Rajcan-Separovic
- Department of Pathology and Lab Medicine, University of British Columbia, Vancouver, BC, Canada.
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Additional cryptic CNVs in mentally retarded patients with apparently balanced karyotypes. Eur J Med Genet 2010; 53:227-33. [PMID: 20542150 DOI: 10.1016/j.ejmg.2010.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 06/01/2010] [Indexed: 01/01/2023]
Abstract
Apparently balanced chromosome abnormalities are occasionally associated with mental retardation (MR). These balanced rearrangements may disrupt genes. However, the phenotype may also be caused by small abnormalities present at the breakpoints or elsewhere in the genome. Conventional karyotyping is not instrumental for detecting small abnormalities because it only identifies genomic imbalances larger than 5-10 Mb. In contrast, high-resolution whole-genome arrays enable the detection of submicroscopic abnormalities in patients with apparently balanced rearrangements. Here, we report on the whole-genome analysis of 13 MR patients with previously detected balanced chromosomal abnormalities, five de novo, four inherited, and four of unknown inheritance, using Single Nucleotide Polymorphism (SNP) arrays. In all the cases, the patient had an abnormal phenotype. In one familial case and one unknown inheritance case, one of the parents had a phenotype which appeared identical to the patient's phenotype. Additional copy number variants (CNVs) were identified in eight patients. Three patients contained CNVs adjacent to one or either breakpoints. One of these patients showed four and two deletions near the breakpoints of a de novo pericentric inversion. In five patients we identified CNVs on chromosomes unrelated to the previously observed genomic imbalance. These data demonstrate that high-resolution array screening and conventional karyotyping is necessary to tie complex karyotypes to phenotypes of MR patients.
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Qiao Y, Harvard C, Tyson C, Liu X, Fawcett C, Pavlidis P, Holden JJA, Lewis MES, Rajcan-Separovic E. Outcome of array CGH analysis for 255 subjects with intellectual disability and search for candidate genes using bioinformatics. Hum Genet 2010; 128:179-94. [PMID: 20512354 DOI: 10.1007/s00439-010-0837-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 05/09/2010] [Indexed: 12/20/2022]
Abstract
Array CGH enables the detection of pathogenic copy number variants (CNVs) in 5-15% of individuals with intellectual disability (ID), making it a promising tool for uncovering ID candidate genes. However, most CNVs encompass multiple genes, making it difficult to identify key disease gene(s) underlying ID etiology. Using array CGH we identified 47 previously unreported unique CNVs in 45/255 probands. We prioritized ID candidate genes using five bioinformatic gene prioritization web tools. Gene priority lists were created by comparing integral genes from each CNV from our ID cohort with sets of training genes specific either to ID or randomly selected. Our findings suggest that different training sets alter gene prioritization only moderately; however, only the ID gene training set resulted in significant enrichment of genes with nervous system function (19%) in prioritized versus non-prioritized genes from the same de novo CNVs (7%, p < 0.05). This enrichment further increased to 31% when the five web tools were used in concert and included genes within mitogen-activated protein kinase (MAPK) and neuroactive ligand-receptor interaction pathways. Gene prioritization web tools enrich for genes with relevant function in ID and more readily facilitate the selection of ID candidate genes for functional studies, particularly for large CNVs.
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Affiliation(s)
- Y Qiao
- Department of Pathology (Cytogenetics), Child and Family Research Institute, University of British Columbia (UBC), 950 West 28th, Room 3060, Vancouver, BC, V5Z 4H4, Canada
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Miller DT, Adam MP, Aradhya S, Biesecker LG, Brothman AR, Carter NP, Church DM, Crolla JA, Eichler EE, Epstein CJ, Faucett WA, Feuk L, Friedman JM, Hamosh A, Jackson L, Kaminsky EB, Kok K, Krantz ID, Kuhn RM, Lee C, Ostell JM, Rosenberg C, Scherer SW, Spinner NB, Stavropoulos DJ, Tepperberg JH, Thorland EC, Vermeesch JR, Waggoner DJ, Watson MS, Martin CL, Ledbetter DH. Consensus statement: chromosomal microarray is a first-tier clinical diagnostic test for individuals with developmental disabilities or congenital anomalies. Am J Hum Genet 2010; 86:749-64. [PMID: 20466091 PMCID: PMC2869000 DOI: 10.1016/j.ajhg.2010.04.006] [Citation(s) in RCA: 1816] [Impact Index Per Article: 129.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 04/12/2010] [Accepted: 04/19/2010] [Indexed: 12/11/2022] Open
Abstract
Chromosomal microarray (CMA) is increasingly utilized for genetic testing of individuals with unexplained developmental delay/intellectual disability (DD/ID), autism spectrum disorders (ASD), or multiple congenital anomalies (MCA). Performing CMA and G-banded karyotyping on every patient substantially increases the total cost of genetic testing. The International Standard Cytogenomic Array (ISCA) Consortium held two international workshops and conducted a literature review of 33 studies, including 21,698 patients tested by CMA. We provide an evidence-based summary of clinical cytogenetic testing comparing CMA to G-banded karyotyping with respect to technical advantages and limitations, diagnostic yield for various types of chromosomal aberrations, and issues that affect test interpretation. CMA offers a much higher diagnostic yield (15%-20%) for genetic testing of individuals with unexplained DD/ID, ASD, or MCA than a G-banded karyotype ( approximately 3%, excluding Down syndrome and other recognizable chromosomal syndromes), primarily because of its higher sensitivity for submicroscopic deletions and duplications. Truly balanced rearrangements and low-level mosaicism are generally not detectable by arrays, but these are relatively infrequent causes of abnormal phenotypes in this population (<1%). Available evidence strongly supports the use of CMA in place of G-banded karyotyping as the first-tier cytogenetic diagnostic test for patients with DD/ID, ASD, or MCA. G-banded karyotype analysis should be reserved for patients with obvious chromosomal syndromes (e.g., Down syndrome), a family history of chromosomal rearrangement, or a history of multiple miscarriages.
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Affiliation(s)
- David T. Miller
- Division of Genetics and Department of Laboratory Medicine, Children's Hospital Boston and Harvard Medical School, Boston, MA, USA
| | - Margaret P. Adam
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA, USA
| | | | - Leslie G. Biesecker
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Arthur R. Brothman
- Department of Pediatrics, Human Genetics, Pathology and ARUP Laboratories, University of Utah School of Medicine, Salt Lake City, UT, USA
| | | | - Deanna M. Church
- National Center for Biotechnology Information, Bethesda, MD, USA
| | - John A. Crolla
- National Genetics Reference Laboratory (Wessex), Salisbury UK
| | - Evan E. Eichler
- Department of Genome Sciences and Howard Hughes Medical Institute, University of Washington School of Medicine, Seattle, WA, USA
| | - Charles J. Epstein
- Institute for Human Genetics and Department of Pediatrics, University of California, San Francisco, San Francisco, CA, USA
| | - W. Andrew Faucett
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Lars Feuk
- Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Jan M. Friedman
- Department of Medical Genetics, University of British Columbia, and Child & Family Research Institute, Vancouver, British Columbia, Canada
| | - Ada Hamosh
- Department of Pediatrics and McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Laird Jackson
- Department of Obstetrics and Gynecology, Drexel University College of Medicine and Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Erin B. Kaminsky
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Klaas Kok
- Department of Genetics, University Medical Centre Groningen, University of Groningen, The Netherlands
| | - Ian D. Krantz
- Department of Pediatrics/Human Genetics, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Robert M. Kuhn
- Center for Biomolecular Science and Engineering, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Charles Lee
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - James M. Ostell
- National Center for Biotechnology Information, Bethesda, MD, USA
| | - Carla Rosenberg
- Department of Genetics and Evolutionary Biology, University Sao Paulo, Brazil
| | - Stephen W. Scherer
- The Centre for Applied Genomics and Program in Genetics and Genetic Biology, The Hospital for Sick Children and Department of Molecular Genetics, University of Toronto, Ontario, Canada
| | - Nancy B. Spinner
- Department of Pediatrics/Human Genetics, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Dimitri J. Stavropoulos
- Department of Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | | | - Erik C. Thorland
- Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | | | - Darrel J. Waggoner
- Department of Human Genetics and Pediatrics, University of Chicago, Chicago, IL, USA
| | | | - Christa Lese Martin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - David H. Ledbetter
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
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32
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Regier DA, Friedman JM, Marra CA. Value for money? Array genomic hybridization for diagnostic testing for genetic causes of intellectual disability. Am J Hum Genet 2010; 86:765-72. [PMID: 20398885 DOI: 10.1016/j.ajhg.2010.03.009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 03/05/2010] [Accepted: 03/16/2010] [Indexed: 01/22/2023] Open
Abstract
Array genomic hybridization (AGH) provides a higher detection rate than does conventional cytogenetic testing when searching for chromosomal imbalance causing intellectual disability (ID). AGH is more costly than conventional cytogenetic testing, and it remains unclear whether AGH provides good value for money. Decision analytic modeling was used to evaluate the trade-off between costs, clinical effectiveness, and benefit of an AGH testing strategy compared to a conventional testing strategy. The trade-off between cost and effectiveness was expressed via the incremental cost-effectiveness ratio. Probabilistic sensitivity analysis was performed via Monte Carlo simulation. The baseline AGH testing strategy led to an average cost increase of $217 (95% CI $172-$261) per patient and an additional 8.2 diagnoses in every 100 tested (0.082; 95% CI 0.044-0.119). The mean incremental cost per additional diagnosis was $2646 (95% CI $1619-$5296). Probabilistic sensitivity analysis demonstrated that there was a 95% probability that AGH would be cost effective if decision makers were willing to pay $4550 for an additional diagnosis. Our model suggests that using AGH instead of conventional karyotyping for most ID patients provides good value for money. Deterministic sensitivity analysis found that employing AGH after first-line cytogenetic testing had proven uninformative did not provide good value for money when compared to using AGH as first-line testing.
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Affiliation(s)
- Dean A Regier
- National Perinatal Epidemiology Unit, University of Oxford, Oxford, UK.
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Li F, Shen Y, Köhler U, Sharkey FH, Menon D, Coulleaux L, Malan V, Rio M, McMullan DJ, Cox H, Fagan KA, Gaunt L, Metcalfe K, Heinrich U, Hislop G, Maye U, Sutcliffe M, Wu BL, Thiel BD, Mulchandani S, Conlin LK, Spinner NB, Murphy KM, Batista DAS. Interstitial microduplication of Xp22.31: Causative of intellectual disability or benign copy number variant? Eur J Med Genet 2010; 53:93-9. [PMID: 20132918 DOI: 10.1016/j.ejmg.2010.01.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 01/23/2010] [Indexed: 12/16/2022]
Abstract
The use of comparative genomic hybridization (CGH) and single nucleotide polymorphism (SNP) arrays has dramatically altered the approach to identification of genetic alterations that can explain intellectual disability and /or congenital anomalies. However, the discovery of numerous copy number changes with benign or unknown clinical significance has made interpretation problematic. Submicroscopic duplication of Xp22.31 has been reported as either a possible cause of intellectual disability and/or developmental delay or a benign variant. Here we report 29 individuals with the microduplication found as part of microarray analysis of 7793 samples submitted to an international group of 13 clinical laboratories. The referral reasons varied and included developmental delay, intellectual disability, autism, dysmorphic features and/or multiple congenital anomalies. The size of the Xp22.31 duplication varied between 149 kb and 1.74 Mb and included the steroid sulfatase (STS) gene with the male to female ratio of 0.7. Duplication within this segment is seen at a frequency of 0.15% in a healthy control population, whereas a frequency of 0.37% was observed in our cohort of individuals with abnormal phenotypes. We present a detailed comparison of the breakpoints, inheritance, X-inactivation and clinical phenotype in our cohort and a review of the literature for a total of 41 patients. To date, this report is the largest compilation of clinical and array data regarding the microduplication of Xp22.31 and will serve to broaden the knowledge of regions involving copy number variation (CNV).
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Affiliation(s)
- Feng Li
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University, Baltimore, MD, USA
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Lee CH, Liu CM, Wen CC, Chang SM, Hwu HG. Genetic copy number variants in sib pairs both affected with schizophrenia. J Biomed Sci 2010; 17:2. [PMID: 20064257 PMCID: PMC2843606 DOI: 10.1186/1423-0127-17-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Accepted: 01/11/2010] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Schizophrenia is a complex disorder with involvement of multiple genes. METHODS In this study, genome-wide screening for DNA copy-number variations (CNVs) was conducted for ten pairs, a total of 20 cases, of affected siblings using oligonucleotide array-based CGH. RESULTS We found negative symptoms were significantly more severe (p < 0.05) in the subgroup that harbored more genetic imbalance (n >== 13, n = number of CNV-disrupted genes) as compared with the subgroup with fewer CNVs (n <== 6), indicating that the degree of genetic imbalance may influence the severity of the negative symptoms of schizophrenia. Four central nervous system (CNS) related genes including CCAAT/enhancer binding protein, delta (CEBPD, 8q11.21), retinoid x receptor, alpha (RXRA, 9q34.2), LIM homeobox protein 5 (LHX5, 12q24.13) and serine/threonine kinase 11 (STK11, 19p13.3) are recurrently (incidence >== 16.7%) disrupted by CNVs. Two genes, PVR (poliovirus receptor) and BU678720, are concordantly deleted in one and two, respectively, pairs of co-affected siblings. However, we did not find a significant association of this BU678720 deletion and schizophrenia in a large case-control sample. CONCLUSIONS We conclude that the high genetic loading of CNVs may be the underlying cause of negative symptoms of schizophrenia, and the CNS-related genes revealed by this study warrant further investigation.
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Affiliation(s)
- Chia-Huei Lee
- National Institute of Cancer Research, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
| | - Chih-Min Liu
- Department of Psychiatry, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chun-Chiang Wen
- Department of Psychiatry, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Shun-Min Chang
- National Institute of Cancer Research, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
| | - Hai-Gwo Hwu
- Department of Psychiatry, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
- Institute of Epidemiology, College of Public Health, National Taiwan University, Taipei, Taiwan
- Department of Psychology, College of Science, National Taiwan University, Taipei, Taiwan
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35
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Manolakos E, Orru S, Neroutsou R, Kefalas K, Louizou E, Papoulidis I, Thomaidis L, Peitsidis P, Sotiriou S, Kitsos G, Tsoplou P, Petersen MB, Metaxotou A. Detailed molecular and clinical investigation of a child with a partial deletion of chromosome 11 (Jacobsen syndrome). Mol Cytogenet 2009; 2:26. [PMID: 20003197 PMCID: PMC2799424 DOI: 10.1186/1755-8166-2-26] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Accepted: 12/09/2009] [Indexed: 01/30/2023] Open
Abstract
Background Jacobsen syndrome (JBS) is a rare chromosomal disorder leading to multiple physical and mental impairment. This syndrome is caused by a partial deletion of chromosome 11, especially subband 11q24.1 has been proven to be involved. Clinical cases may easily escape diagnosis, however pancytopenia or thrombocytopenia may be indicative for JBS. Results We report a 7.5 years old boy presenting with speech development delay, hearing impairment and abnormal platelet function. High resolution SNP oligonucleotide microarray analysis revealed a terminal deletion of 11.4 Mb in size, in the area 11q24.1-11qter. This specific deletion encompasses around 170 genes. Other molecular techniques such as fluorescence in situ hybridization and multiplex ligation-dependent probe amplification were used to confirm the array-result. Discussion Our results suggest that the identification and detailed analysis of similar patients with abnormal platelet function and otherwise mild clinical features will contribute to identification of more patients with 11q deletion and JBS.
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36
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Jaillard S, Drunat S, Bendavid C, Aboura A, Etcheverry A, Journel H, Delahaye A, Pasquier L, Bonneau D, Toutain A, Burglen L, Guichet A, Pipiras E, Gilbert-Dussardier B, Benzacken B, Martin-Coignard D, Henry C, David A, Lucas J, Mosser J, David V, Odent S, Verloes A, Dubourg C. Identification of gene copy number variations in patients with mental retardation using array-CGH: Novel syndromes in a large French series. Eur J Med Genet 2009; 53:66-75. [PMID: 19878743 DOI: 10.1016/j.ejmg.2009.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Accepted: 10/17/2009] [Indexed: 12/16/2022]
Abstract
Array-CGH has revealed a large number of copy number variations (CNVs) in patients with multiple congenital anomalies and/or mental retardation (MCA/MR). According to criteria recently listed, pathogenicity was clearly suspected for some CNVs but benign CNVs, considered as polymorphisms, have complicated the interpretation of the results. In this study, genomic DNAs from 132 French patients with unexplained mental retardation were analysed by genome wide high-resolution Agilent 44K oligonucleotide arrays. The results were in accordance with those observed in previous studies: the detection rate of pathogenic CNVs was 14.4%. A non-random involvement of several chromosomal regions was observed. Some of the microimbalances recurrently involved regions (1q21.1, 2q23.1, 2q32q33, 7p13, 17p13.3, 17p11.2, 17q21.31) corresponding to known or novel syndromes. For all the pathogenic CNVs, further cases are needed to allow more accurate genotype-phenotype correlations underscoring the importance of databases to group patients with similar molecular data.
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Affiliation(s)
- Sylvie Jaillard
- Laboratoire de Cytogénétique et Biologie Cellulaire, CHU Pontchaillou, Rennes, France.
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Shaffer LG, Bejjani BA. Using microarray-based molecular cytogenetic methods to identify chromosome abnormalities. Pediatr Ann 2009; 38:440-7. [PMID: 19711882 DOI: 10.3928/00904481-20090723-08] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Hochstenbach R, van Binsbergen E, Engelen J, Nieuwint A, Polstra A, Poddighe P, Ruivenkamp C, Sikkema-Raddatz B, Smeets D, Poot M. Array analysis and karyotyping: Workflow consequences based on a retrospective study of 36,325 patients with idiopathic developmental delay in the Netherlands. Eur J Med Genet 2009; 52:161-9. [DOI: 10.1016/j.ejmg.2009.03.015] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Accepted: 03/27/2009] [Indexed: 12/20/2022]
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A new diagnostic workflow for patients with mental retardation and/or multiple congenital abnormalities: test arrays first. Eur J Hum Genet 2009; 17:1394-402. [PMID: 19436329 DOI: 10.1038/ejhg.2009.74] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
High-density single-nucleotide polymorphism (SNP) genotyping technology enables extensive genotyping as well as the detection of increasingly smaller chromosomal aberrations. In this study, we assess molecular karyotyping as first-round analysis of patients with mental retardation and/or multiple congenital abnormalities (MR/MCA). We used different commercially available SNP array platforms, the Affymetrix GeneChip 262K NspI, the Genechip 238K StyI, the Illumina HumanHap 300 and HumanCNV 370 BeadChip, to detect copy number variants (CNVs) in 318 patients with unexplained MR/MCA. We found abnormalities in 22.6% of the patients, including six CNVs that overlap known microdeletion/duplication syndromes, eight CNVs that overlap recently described syndromes, 63 potentially pathogenic CNVs (in 52 patients), four large segments of homozygosity and two mosaic trisomies for an entire chromosome. This study shows that high-density SNP array analysis reveals a much higher diagnostic yield as that of conventional karyotyping. SNP arrays have the potential to detect CNVs, mosaics, uniparental disomies and loss of heterozygosity in one experiment. We, therefore, propose a novel diagnostic approach to all MR/MCA patients by first analyzing every patient with an SNP array instead of conventional karyotyping.
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Tyson C, Dawson A, Bal S, Tomiuk M, Anderson T, Tucker D, Riordan D, Chudoba I, Morash B, Mhanni A, Chudley A, McGillivray B, Parslow M, Rappold G, Roeth R, Fawcett C, Qiao Y, Harvard C, Rajcan-Separovic E. Molecular cytogenetic investigation of two patients with Y chromosome rearrangements and intellectual disability. Am J Med Genet A 2009; 149A:490-5. [DOI: 10.1002/ajmg.a.32535] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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41
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Koolen DA, Pfundt R, de Leeuw N, Hehir-Kwa JY, Nillesen WM, Neefs I, Scheltinga I, Sistermans E, Smeets D, Brunner HG, van Kessel AG, Veltman JA, de Vries BB. Genomic microarrays in mental retardation: A practical workflow for diagnostic applications. Hum Mutat 2009; 30:283-92. [DOI: 10.1002/humu.20883] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kim JS, Yoo JY, Lee KS, Kim HS, Choi JS, Rha HK, Yim SV, Lee KH. Comparative genome hybridization array analysis for sporadic Parkinson's disease. Int J Neurosci 2009; 118:1331-45. [PMID: 18698514 DOI: 10.1080/00207450802174522] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Parkinson disease (PD) is a common neurodegenerative disorder, characterized by the loss of midbrain dopamine neurons and Lewy body inclusions. We investigated array CGH to analyze gain or loss of genetic material from 30 patients with PD. We identified the frequent copy number variations in PD; gains in 1p21.1, 4p15.31, 5p15.33, 6q24.1, 7q35, 8q24.3, 10q26.3, 11p15.5-15.4, 12q21.2, 16p13.3, 18q12.3 and 22q13.31, and losses in 1p36.33, and 5q13.2. These findings enable a better description of genetic variations in PD, and could provide a foundation for understanding the critical regions of the genome that may be involved in the development of PD.
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Affiliation(s)
- Joong-Seok Kim
- Department of Neurology, The Catholic University of Korea, Seoul, Republic of Korea.
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Abstract
Mental retardation--known more commonly nowadays as intellectual disability--is a severe neurological condition affecting up to 3% of the general population. As a result of the analysis of familial cases and recent advances in clinical genetic testing, great strides have been made in our understanding of the genetic etiologies of mental retardation. Nonetheless, no treatment is currently clinically available to patients suffering from intellectual disability. Several animal models have been used in the study of memory and cognition. Established paradigms in Drosophila have recently captured cognitive defects in fly mutants for orthologs of genes involved in human intellectual disability. We review here three protocols designed to understand the molecular genetic basis of learning and memory in Drosophila and the genes identified so far with relation to mental retardation. In addition, we explore the mental retardation genes for which evidence of neuronal dysfunction other than memory has been established in Drosophila. Finally, we summarize the findings in Drosophila for mental retardation genes for which no neuronal information is yet available. All in all, this review illustrates the impressive overlap between genes identified in human mental retardation and genes involved in physiological learning and memory.
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Affiliation(s)
- François V Bolduc
- Watson School of Biological Sciences, Cold Spring Harbor, New York, USA
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44
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Tyson C, Qiao Y, Harvard C, Liu X, Bernier FP, McGillivray B, Farrell SA, Arbour L, Chudley AE, Clarke L, Gibson W, Dyack S, McLeod R, Costa T, Vanallen MI, Yong SL, Graham GE, Macleod P, Patel MS, Hurlburt J, Holden JJ, Lewis SM, Rajcan-Separovic E. Submicroscopic deletions of 11q24-25 in individuals without Jacobsen syndrome: re-examination of the critical region by high-resolution array-CGH. Mol Cytogenet 2008; 1:23. [PMID: 19000322 PMCID: PMC2648978 DOI: 10.1186/1755-8166-1-23] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Accepted: 11/11/2008] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Jacobsen syndrome is a rare contiguous gene disorder that results from a terminal deletion of the long arm of chromosome 11. It is typically characterized by intellectual disability, a variety of physical anomalies and a distinctive facial appearance. The 11q deletion has traditionally been identified by routine chromosome analysis. Array-based comparative genomic hybridization (array-CGH) has offered new opportunities to identify and refine chromosomal abnormalities in regions known to be associated with clinical syndromes. RESULTS Using the 1 Mb BAC array (Spectral Genomics), we screened 70 chromosomally normal children with idiopathic intellectual disability (ID) and congenital abnormalities, and identified five cases with submicroscopic abnormalities believed to contribute to their phenotypes. Here, we provide detailed molecular cytogenetic descriptions and clinical presentation of two unrelated subjects with de novo submicroscopic deletions within chromosome bands 11q24-25. In subject 1 the chromosome rearrangement consisted of a 6.18 Mb deletion (from 128.25-134.43 Mb) and an adjacent 5.04 Mb duplication (from 123.15-128.19 Mb), while in subject 2, a 4.74 Mb interstitial deletion was found (from 124.29-129.03 Mb). Higher resolution array analysis (385 K Nimblegen) was used to refine all breakpoints. Deletions of the 11q24-25 region are known to be associated with Jacobsen syndrome (JBS: OMIM 147791). However, neither of the subjects had the typical features of JBS (trigonocephaly, platelet disorder, heart abnormalities). Both subjects had ID, dysmorphic features and additional phenotypic abnormalities: subject 1 had a kidney abnormality, bilateral preauricular pits, pectus excavatum, mild to moderate conductive hearing loss and behavioral concerns; subject 2 had macrocephaly, an abnormal MRI with delayed myelination, fifth finger shortening and squaring of all fingertips, and sensorineural hearing loss. CONCLUSION Two individuals with ID who did not have the typical clinical features of Jacobsen syndrome were found to have deletions within the JBS region at 11q24-25. Their rearrangements facilitate the refinement of the JBS critical region and suggest that a) deletion of at least 3 of the 4 platelet function critical genes (ETS-1, FLI-1 and NFRKB and JAM3) is necessary for thrombocytopenia; b) one of the critical regions for heart abnormalities (conotruncal heart defects) may lie within 129.03 - 130.6 Mb; c) deletions of KCNJ1 and ADAMTS15 may contribute to the renal anomalies in Jacobsen Syndrome; d) the critical region for MRI abnormalities involves a region from 124.6 - 129.03 Mb. Our results reiterate the benefits of array-CGH for description of new phenotype/genotype associations and refinement of previously established ones.
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Affiliation(s)
- Christine Tyson
- Department of Pathology and Laboratory Medicine and Child and Family Research Institute (CFRI), UBC, Vancouver, BC, Canada.
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Callier P, Faivre L, Thauvin-Robinet C, Marle N, Mosca AL, D'Athis P, Guy J, Masurel-Paulet A, Joly L, Guiraud S, Teyssier JR, Huet F, Mugneret F. Array-CGH in a series of 30 patients with mental retardation, dysmorphic features, and congenital malformations detected an interstitial 1p22.2-p31.1 deletion in a patient with features overlapping the Goldenhar syndrome. Am J Med Genet A 2008; 146A:2109-15. [PMID: 18629884 DOI: 10.1002/ajmg.a.32447] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Genosensor Array 300 (Abbott) is a multiplex platform for array-based comparative genomic hybridization that detects unbalanced genomic aberrations including whole chromosome gains/losses, microdeletions, duplications and unbalanced subtelomeric rearrangements. A series of 30 patients with unexplained mental retardation, dysmorphic features, congenital abnormalities and normal high resolution karyotype and FISH subtelomeric studies were analyzed using Genosensor Array 300 array-CGH. We identified a chromosomal aberration in one patient with an interstitial 1p31.1 deletion. FISH analysis with BACs specific probes of the 1p region confirmed the interstitial 1p22.2-p31.1 deletion. The patient was a 20-year-old man with short stature, facial dysmorphism including asymmetry, scoliosis, severe psychomotor delay and an epibulbar dermoid cyst. The phenotype was compatible with Goldenhar syndrome despite the absence of asymmetric ears. This observation is of interest since it could be a clue in the search for the genes responsible for Goldenhar syndrome. This study demonstrates the utility of the array-CGH technology in detecting interstitial deletions.
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Affiliation(s)
- P Callier
- Département de Génétique, Hôpital Le Bocage, Dijon, France.
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Ou Z, Kang SHL, Shaw CA, Carmack CE, White LD, Patel A, Beaudet AL, Cheung SW, Chinault AC. Bacterial artificial chromosome-emulation oligonucleotide arrays for targeted clinical array-comparative genomic hybridization analyses. Genet Med 2008; 10:278-89. [PMID: 18414211 DOI: 10.1097/gim.0b013e31816b4420] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE The goal of this work was to test the ability of oligonucleotide-based arrays to reproduce the results of focused bacterial artificial chromosome (BAC)-based arrays used clinically in comparative genomic hybridization experiments to detect constitutional copy number changes in genomic DNA. METHODS Custom oligonucleotide (oligo) arrays were designed using the Agilent Technologies platform to give high-resolution coverage of regions within the genome sequence coordinates of BAC/P1 artificial chromosome (PAC) clones that had already been validated for use in previous versions of clone arrays used in clinical practice. Standard array-comparative genomic hybridization experiments, including a simultaneous blind analysis of a set of clinical samples, were conducted on both array platforms to identify copy number differences between patient samples and normal reference controls. RESULTS Initial experiments successfully demonstrated the capacity of oligo arrays to emulate BAC data without the need for dye-reversal comparisons. Empirical data and computational analyses of oligo response and distribution from a pilot array were used to design an optimized array of 44,000 oligos (44K). This custom 44K oligo array consists of probes localized to the genomic positions of >1400 fluorescence in situ hybridization-verified BAC/PAC clones covering more than 140 regions implicated in genetic diseases, as well as all clinically relevant subtelomeric and pericentromeric regions. CONCLUSIONS Our data demonstrate that oligo-based arrays offer a valid alternative for focused BAC arrays. Furthermore, they have significant advantages, including better design flexibility, avoidance of repetitive sequences, manufacturing processes amenable to good manufacturing practice standards in the future, increased robustness because of an enhanced dynamic range (signal to background), and increased resolution that allows for detection of smaller regions of change.
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Affiliation(s)
- Zhishuo Ou
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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Chromosomal map of human brain malformations. Hum Genet 2008; 124:73-80. [PMID: 18563447 DOI: 10.1007/s00439-008-0528-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 06/12/2008] [Indexed: 01/10/2023]
Abstract
The etiology of most central nervous system (CNS) malformations remains unknown. We have utilized the fact that autosomal chromosome aberrations are commonly associated with CNS malformations to identify new causative gene loci. The human cytogenetic database, a computerized catalog of the clinical phenotypes associated with cytogenetically detectable human chromosome aberrations, was used to identify patients with 14 selected brain malformations including 541 with deletions, and 290 carrying duplications. These cases were used to develop an autosomal deletion and duplication map consisting of 67 different deleted malformation associated bands (MABs) in 55 regions and 88 different duplicated MABs in 36 regions; 31 of the deleted and 8 duplicated MABs were highly significantly associated (P < 0.001). All holoprosencephaly MABs found in the database contained a known HPE gene providing some level of validation for the approach. Significantly associated MABs are discussed for each malformation together with the published data about known disease-causing genes and reported malformation-associated loci, as well as the limitations of the proposed approach.
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Medical genetics diagnostic evaluation of the child with global developmental delay or intellectual disability. Curr Opin Neurol 2008; 21:117-22. [DOI: 10.1097/wco.0b013e3282f82c2d] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Rassekh SR, Chan S, Harvard C, Dix D, Qiao Y, Rajcan-Separovic E. Screening for submicroscopic chromosomal rearrangements in Wilms tumor using whole-genome microarrays. ACTA ACUST UNITED AC 2008; 182:84-94. [DOI: 10.1016/j.cancergencyto.2007.12.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 12/19/2007] [Accepted: 12/28/2007] [Indexed: 12/22/2022]
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Abstract
All children with an intellectual disability (mental retardation) or global developmental delay should have a comprehensive evaluation to establish the etiology of the disability. A specific etiologic diagnosis offers the opportunity to discuss treatment, prognosis, and genetic recurrence risk. A diagnosis also avoids unnecessary testing and can lead to opportunities for improved health and functional outcomes. The key elements of the diagnostic evaluation are the medical and developmental history, 3-generation family history, dysmorphologic examination, neurologic examination, and judicious use of the laboratory and neuroimaging. All published guidelines for the evaluation of children with intellectual disability acknowledge that there is a substantial percentage of patients who are undiagnosed after a comprehensive evaluation and who deserve ongoing follow-up for the purpose of establishing a diagnosis. Recently, studies of the clinical application of array comparative genomic hybridization (aCGH) to individuals with intellectual disability indicate that this approach provides a diagnosis in as much as 10% of patients and that this technique is replacing the use of fluorescent in situ hybridization for subtelomere imbalances now used for such patients when the standard karyotype is normal. The literature suggests that history and examination by an expert clinician will lead to a diagnosis in 2 of 3 patients in whom a diagnosis is made. Laboratory studies alone, including neuroimaging, provide a diagnosis in the remaining one third. The approach to the evaluation of the patient in whom an etiologic diagnosis is not suspected after the history and physical examinations includes a standard karyotype, Fragile X molecular genetic testing, aCGH, and neuroimaging, based on the evidence to date. One can expect rapid changes in the microarray technology in the near future.
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