1
|
Kinoshita T, Mikami M, Ayabe T, Matsubara K, Ono H, Ohki K, Fukami M, Katoh-Fukui Y. Frequency of Common Copy-Number Variations at 15q11.2q13 in Sperm of Healthy Men. Cytogenet Genome Res 2019; 159:66-73. [PMID: 31639787 DOI: 10.1159/000503267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2019] [Indexed: 11/19/2022] Open
Abstract
The genomic region at 15q11.2q13 represents a hotspot for copy-number variations (CNVs) due to nonallelic homologous recombination. Previous studies have suggested that the development of 15q11.2q13 deletions in sperm may be affected by seasonal factors because patients with Prader-Willi syndrome resulting from 15q11.2q13 deletions on paternally derived chromosomes showed autumn-dominant birth seasonality. The present study aimed to determine the frequency of 15q11.2q13 CNVs in sperm of healthy men and clarify the effects of various environmental factors, i.e., age, smoking status, alcohol intake, and season, on the frequency. Thirty volunteers were asked to provide semen samples and clinical information once in each season of a year. The rates of 15q11.2q13 CNVs were examined using 2-color FISH. The results were statistically analyzed using a generalized estimating equation with negative binomial distribution and a log link function. Consequently, informative data were obtained from 83 samples of 26 individuals. The rates of deletions and duplications ranged from 0.04 to 0.48% and from 0.08 to 0.30%, respectively. The rates were not correlated with the age, smoking status, or alcohol intake. Sperm produced in winter showed 1.2 to 1.4-fold high rates for both deletions and duplications as compared with sperm produced in the other seasons; however, there was no significant difference. These results demonstrate high and variable CNV rates at 15q11.2q13 in sperm of healthy men. These CNVs appear to occur independent of the age, smoking status, or alcohol intake, while the effect of season remains inconclusive. Our results merit further validation.
Collapse
|
2
|
Genetic Imbalances in Argentinean Patients with Congenital Conotruncal Heart Defects. Genes (Basel) 2018; 9:genes9090454. [PMID: 30208644 PMCID: PMC6162499 DOI: 10.3390/genes9090454] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/23/2018] [Accepted: 09/05/2018] [Indexed: 02/07/2023] Open
Abstract
Congenital conotruncal heart defects (CCHD) are a subset of serious congenital heart defects (CHD) of the cardiac outflow tracts or great arteries. Its frequency is estimated in 1/1000 live births, accounting for approximately 10–30% of all CHD cases. Chromosomal abnormalities and copy number variants (CNVs) contribute to the disease risk in patients with syndromic and/or non-syndromic forms. Although largely studied in several populations, their frequencies are barely reported for Latin American countries. The aim of this study was to analyze chromosomal abnormalities, 22q11 deletions, and other genomic imbalances in a group of Argentinean patients with CCHD of unknown etiology. A cohort of 219 patients with isolated CCHD or associated with other major anomalies were referred from different provinces of Argentina. Cytogenetic studies, Multiplex-Ligation-Probe-Amplification (MLPA) and fluorescent in situ hybridization (FISH) analysis were performed. No cytogenetic abnormalities were found. 22q11 deletion was found in 23.5% of the patients from our cohort, 66% only had CHD with no other major anomalies. None of the patients with transposition of the great vessels (TGV) carried the 22q11 deletion. Other 4 clinically relevant CNVs were also observed: a distal low copy repeat (LCR)D-E 22q11 duplication, and 17p13.3, 4q35 and TBX1 deletions. In summary, 25.8% of CCHD patients presented imbalances associated with the disease.
Collapse
|
3
|
Kovaleva NV, Cotter PD. Mosaicism for structural non-centromeric autosomal rearrangements in disease-defined carriers: sex differences in the rearrangements profile and maternal age distributions. Mol Cytogenet 2017; 10:18. [PMID: 28533817 PMCID: PMC5438540 DOI: 10.1186/s13039-017-0321-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 05/13/2017] [Indexed: 02/08/2023] Open
Abstract
Background Mosaicism for an autosomal structural rearrangement (Rea) associated with clinical manifestation of chromosomal imbalance is rare. Consequently, there is a lack of basic epidemiological characterization of this kind of mosaicism, such as population rate, cytogenetic profile of Reas involved, maternal age distribution, and sex (male to female) ratio among Rea carriers. The objectives of the present study were: (i) determination of the Rea profile in clinically affected individuals, (ii) comparative analysis of the cytogenetic profile and involvement of single chromosomes to rearrangements in affected and previously reported asymptomatic carriers, (iii) analysis of the male/female ratio in carriers of various types of Rea, and, (iv) examination of parental ages distributions according to carriers’ sex. Results Two hundred and forty six disease-defined cases of mosaicism for autosomal non-centromeric Rea with a normal cell line of known sex were identified from the literature. There was a significant difference in single chromosome involvements compared to structural rearrangements between affected and asymptomatic carriers of unbalanced Rea, p =0.0030. In affected carriers, chromosome 18 was most frequently involved in structural rearrangements (12.6% of 246 instances). The least frequently rearranged were chromosomes 16 and 21 (0.8% and 1.2%, respectively). In asymptomatic carriers, the most frequently rearranged were chromosomes 5 and 21 (13% of 51 instances each). Among carriers of “loss” or “gain/loss” of genomic material, a female predominance was observed (50 M/89 F, different from population ratio of 1.06 at p = 0.0002). Carriers of either “gain” or balanced Rea demonstrated typical male predominance (41 M/30 F and 18 M/16 F), not different from 1.06. Maternal and paternal ages were reported in 129 and in 109 cases, respectively. There was a significant difference in maternal age distribution between male and female carriers, with mean maternal age of 25.2 years vs 28.3 years (p = 0.032). However, there was no difference in paternal age, with mean paternal age of 29.4 in both groups. Conclusion The data suggested that structural rearrangements of certain chromosomes involved in mosaicism may not be tolerated by the embryo, while others have higher survival prospects. Maternal age appears to be a risk factor for somatic mosaicism of structural Rea in female offspring or might cause an adverse effect on male embryo viability. Electronic supplementary material The online version of this article (doi:10.1186/s13039-017-0321-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Natalia V Kovaleva
- Academy of Molecular Medicine, Mytniskaya str. 12/44, St. Petersburg, 191144 Russian Federation
| | - Philip D Cotter
- Department of Pediatrics, University of California San Francisco, San Francisco, CA USA.,ResearchDx Inc., Irvine, CA USA
| |
Collapse
|
4
|
An exploratory study of predisposing genetic factors for DiGeorge/velocardiofacial syndrome. Sci Rep 2017; 7:40031. [PMID: 28059126 PMCID: PMC5216377 DOI: 10.1038/srep40031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/01/2016] [Indexed: 12/13/2022] Open
Abstract
DiGeorge/velocardiofacial syndrome (DGS/VCFS) is a disorder caused by a 22q11.2 deletion mediated by non-allelic homologous recombination (NAHR) between low-copy repeats (LCRs). We have evaluated the role of LCR22 genomic architecture and PRDM9 variants as DGS/VCFS predisposing factors. We applied FISH using fosmid probes on chromatin fibers to analyze the number of tandem repeat blocks in LCR22 in two DGS/VCFS fathers-of-origin with proven 22q11.2 NAHR susceptibility. Results revealed copy number variations (CNVs) of L9 and K3 fosmids in these individuals compared to controls. The total number of L9 and K3 copies was also characterized using droplet digital PCR (ddPCR). Although we were unable to confirm variations, we detected an additional L9 amplicon corresponding to a pseudogene. Moreover, none of the eight DGS/VCFS parents-of-origin was heterozygote for the inv(22)(q11.2) haplotype. PRDM9 sequencing showed equivalent allelic distributions between DGS/VCFS parents-of-origin and controls, although a new PRDM9 allele (L50) was identified in one case. Our results support the hypothesis that LCR22s variations influences 22q11.2 NAHR events, however further studies are needed to confirm this association and clarify the contribution of pseudogenes and rare PDRM9 alleles to NAHR susceptibility.
Collapse
|
5
|
Isles AR, Ingason A, Lowther C, Walters J, Gawlick M, Stöber G, Rees E, Martin J, Little RB, Potter H, Georgieva L, Pizzo L, Ozaki N, Aleksic B, Kushima I, Ikeda M, Iwata N, Levinson DF, Gejman PV, Shi J, Sanders AR, Duan J, Willis J, Sisodiya S, Costain G, Werge TM, Degenhardt F, Giegling I, Rujescu D, Hreidarsson SJ, Saemundsen E, Ahn JW, Ogilvie C, Girirajan SD, Stefansson H, Stefansson K, O’Donovan MC, Owen MJ, Bassett A, Kirov G. Parental Origin of Interstitial Duplications at 15q11.2-q13.3 in Schizophrenia and Neurodevelopmental Disorders. PLoS Genet 2016; 12:e1005993. [PMID: 27153221 PMCID: PMC4859484 DOI: 10.1371/journal.pgen.1005993] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/25/2016] [Indexed: 11/24/2022] Open
Abstract
Duplications at 15q11.2-q13.3 overlapping the Prader-Willi/Angelman syndrome (PWS/AS) region have been associated with developmental delay (DD), autism spectrum disorder (ASD) and schizophrenia (SZ). Due to presence of imprinted genes within the region, the parental origin of these duplications may be key to the pathogenicity. Duplications of maternal origin are associated with disease, whereas the pathogenicity of paternal ones is unclear. To clarify the role of maternal and paternal duplications, we conducted the largest and most detailed study to date of parental origin of 15q11.2-q13.3 interstitial duplications in DD, ASD and SZ cohorts. We show, for the first time, that paternal duplications lead to an increased risk of developing DD/ASD/multiple congenital anomalies (MCA), but do not appear to increase risk for SZ. The importance of the epigenetic status of 15q11.2-q13.3 duplications was further underlined by analysis of a number of families, in which the duplication was paternally derived in the mother, who was unaffected, whereas her offspring, who inherited a maternally derived duplication, suffered from psychotic illness. Interestingly, the most consistent clinical characteristics of SZ patients with 15q11.2-q13.3 duplications were learning or developmental problems, found in 76% of carriers. Despite their lower pathogenicity, paternal duplications are less frequent in the general population with a general population prevalence of 0.0033% compared to 0.0069% for maternal duplications. This may be due to lower fecundity of male carriers and differential survival of embryos, something echoed in the findings that both types of duplications are de novo in just over 50% of cases. Isodicentric chromosome 15 (idic15) or interstitial triplications were not observed in SZ patients or in controls. Overall, this study refines the distinct roles of maternal and paternal interstitial duplications at 15q11.2-q13.3, underlining the critical importance of maternally expressed imprinted genes in the contribution of Copy Number Variants (CNVs) at this interval to the incidence of psychotic illness. This work will have tangible benefits for patients with 15q11.2-q13.3 duplications by aiding genetic counseling. The genetic interval 15q11.2-q13.3 on human chromosome 15 contains several so-called “imprinted genes” which are subject to epigenetic marking leading to activity from only one parental copy. This is in contrast to non-imprinted genes, whose activity is independent of their parent-of-origin. Deletions affecting the 15q11.2-q13.3 interval cause Prader-Willi and Angelman syndromes (PWS/AS), depending on whether the deletions are paternally or maternally derived respectively. Duplications at the PWS/AS interval region may also lead to neurodevelopmental disorders, including developmental delay (DD), autism spectrum disorder (ASD) and schizophrenia (SZ). Due to presence of imprinted genes within the region, the parental origin of these duplications may be key to the pathogenicity. We show, for the first time, that paternal duplications lead to an increased risk of developing DD/ASD/multiple congenital anomalies (MCA) but, unlike maternal duplication, do not appear to increase risk for SZ. This study refines the distinct roles of maternal and paternal duplications at 15q11.2-q13.3, underlining the critical importance of maternally active imprinted genes in the contribution to the incidence of psychotic illness. This work will have tangible benefits for patients with 15q11.2-q13.3 duplications by aiding genetic counseling.
Collapse
Affiliation(s)
- Anthony R. Isles
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | | | - Chelsea Lowther
- Clinical Genetics Research Program, Centre for Addiction & Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - James Walters
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | | | | | - Elliott Rees
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | - Joanna Martin
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | - Rosie B. Little
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | - Harry Potter
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | | | - Lucilla Pizzo
- Department of Biochemistry and Molecular Biology and Department of Anthropology, University Park, Pennsylvania, United States of America
| | - Norio Ozaki
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya City, Aichi, Japan
| | - Branko Aleksic
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya City, Aichi, Japan
| | - Itaru Kushima
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya City, Aichi, Japan
| | - Masashi Ikeda
- Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, Japan
| | - Nakao Iwata
- Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, Japan
| | - Douglas F. Levinson
- Department of Psychiatry, Stanford University, Palo Alto, California, United States of America
| | - Pablo V. Gejman
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California, United States of America
| | - Jianxin Shi
- Biostatistics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Medical Center Drive, Bethesda, Maryland, United States of America
| | - Alan R. Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem, Evanston, Illinois, United States of America; Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, United States of America
| | - Jubao Duan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California, United States of America
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem, Evanston, Illinois, United States of America; Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, United States of America
| | - Joseph Willis
- UCL Institute of Neurology, Queen Square, London, United Kingdom
| | - Sanjay Sisodiya
- UCL Institute of Neurology, Queen Square, London, United Kingdom
| | - Gregory Costain
- Clinical Genetics Research Program, Centre for Addiction & Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - Thomas M. Werge
- Institute of Biological Psychiatry, Mental Health Centre Sct. Hans, Mental Health Services Copenhagen, University of Copenhagen, Copenhagen, Denmark
| | | | - Ina Giegling
- Department of Psychiatry, University of Halle, Halle, Germany
| | - Dan Rujescu
- Department of Psychiatry, University of Halle, Halle, Germany
| | | | - Evald Saemundsen
- The State Diagnostic and Counselling Centre, Kópavogur, Iceland
- Faculty of Medicine, University of Iceland, Reykjavík, Iceland
| | - Joo Wook Ahn
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Caroline Ogilvie
- Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Santhosh D. Girirajan
- Department of Biochemistry and Molecular Biology and Department of Anthropology, University Park, Pennsylvania, United States of America
| | | | | | - Michael C. O’Donovan
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | - Michael J. Owen
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
- * E-mail: (MJO); (GK)
| | - Anne Bassett
- Clinical Genetics Research Program, Centre for Addiction & Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - George Kirov
- Cardiff University, MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
- * E-mail: (MJO); (GK)
| |
Collapse
|
6
|
Demaerel W, Hosseinzadeh M, Nouri N, Sedghi M, Dimitriadou E, Salehi M, Abdali H, Memarzadeh M, Zamani M, Vermeesch JR. Reciprocal 22q11.2 Deletion and Duplication in Siblings with Karyotypically Normal Parents. Cytogenet Genome Res 2016; 148:1-5. [PMID: 27055209 DOI: 10.1159/000445089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2016] [Indexed: 11/19/2022] Open
Abstract
The 22q11.2 locus is known to harbor a high risk for structural variation caused by non-allelic homologous recombination, resulting in deletions and duplications. Here, we describe the first family with one sibling carrying the 22q11 deletion and the other carrying the reciprocal duplication. FISH and SNP array analysis of the parents show a maternal origin for both deletion and duplication, without indications of balanced deletions/duplications or mosaicism. We hypothesize that germline mosaicism in the mother underlies the deletion and duplication, which would implicate a high recurrence risk for her offspring.
Collapse
Affiliation(s)
- Wolfram Demaerel
- Laboratory for Cytogenetics and Genome Research, Center of Human Genetics, KU Leuven, Leuven, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Meechan DW, Maynard TM, Tucker ES, Fernandez A, Karpinski BA, Rothblat LA, LaMantia AS. Modeling a model: Mouse genetics, 22q11.2 Deletion Syndrome, and disorders of cortical circuit development. Prog Neurobiol 2015; 130:1-28. [PMID: 25866365 DOI: 10.1016/j.pneurobio.2015.03.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 03/24/2015] [Accepted: 03/29/2015] [Indexed: 12/21/2022]
Abstract
Understanding the developmental etiology of autistic spectrum disorders, attention deficit/hyperactivity disorder and schizophrenia remains a major challenge for establishing new diagnostic and therapeutic approaches to these common, difficult-to-treat diseases that compromise neural circuits in the cerebral cortex. One aspect of this challenge is the breadth and overlap of ASD, ADHD, and SCZ deficits; another is the complexity of mutations associated with each, and a third is the difficulty of analyzing disrupted development in at-risk or affected human fetuses. The identification of distinct genetic syndromes that include behavioral deficits similar to those in ASD, ADHC and SCZ provides a critical starting point for meeting this challenge. We summarize clinical and behavioral impairments in children and adults with one such genetic syndrome, the 22q11.2 Deletion Syndrome, routinely called 22q11DS, caused by micro-deletions of between 1.5 and 3.0 MB on human chromosome 22. Among many syndromic features, including cardiovascular and craniofacial anomalies, 22q11DS patients have a high incidence of brain structural, functional, and behavioral deficits that reflect cerebral cortical dysfunction and fall within the spectrum that defines ASD, ADHD, and SCZ. We show that developmental pathogenesis underlying this apparent genetic "model" syndrome in patients can be defined and analyzed mechanistically using genomically accurate mouse models of the deletion that causes 22q11DS. We conclude that "modeling a model", in this case 22q11DS as a model for idiopathic ASD, ADHD and SCZ, as well as other behavioral disorders like anxiety frequently seen in 22q11DS patients, in genetically engineered mice provides a foundation for understanding the causes and improving diagnosis and therapy for these disorders of cortical circuit development.
Collapse
Affiliation(s)
- Daniel W Meechan
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States
| | - Thomas M Maynard
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States
| | - Eric S Tucker
- Department of Neurobiology and Anatomy, Neuroscience Graduate Program, and Center for Neuroscience, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Alejandra Fernandez
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States
| | - Beverly A Karpinski
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States
| | - Lawrence A Rothblat
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States; Department of Psychology, The George Washington University, Washington, DC, United States
| | - Anthony-S LaMantia
- Institute for Neuroscience, Department of Pharmacology & Physiology, The George Washington University, Washington, DC, United States.
| |
Collapse
|
8
|
Yang A, Lee YH, Nam SY, Jeong YJ, Kyung Y, Huh R, Lee J, Kwun Y, Cho SY, Jin DK. Birth seasonality in Korean Prader-Willi syndrome with chromosome 15 microdeletion. Ann Pediatr Endocrinol Metab 2015; 20:40-5. [PMID: 25883926 PMCID: PMC4397272 DOI: 10.6065/apem.2015.20.1.40] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 12/09/2014] [Accepted: 12/30/2014] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Prader-Willi syndrome (PWS) is a well-known genetic disorder, and microdeletion on chromosome 15 is the most common causal mechanism. Several previous studies have suggested that various environmental factors might be related to the pathogenesis of microdeletion in PWS. In this study, we investigated birth seasonality in Korean PWS. METHODS A total of 211 PWS patients born from 1980 to 2014 were diagnosed by methylation polymerase chain reaction at Samsung Medical Center. Of the 211 patients, 138 were born from 2000-2013. Among them, the 74 patients of a deletion group and the 22 patients of a maternal uniparental disomy (UPD) group were compared with general populations born from 2000 using the Walter and Elwood method and cosinor analysis. RESULTS There was no statistical significance in seasonal variation in births of the total 211 patients with PWS (χ(2)=7.2522, P=0.2982). However, a significant difference was found in the monthly variation between PWS with the deletion group and the at-risk general population (P<0.05). In the cosinor model, the peak month of birth for PWS patients in the deletion group was January, while the nadir occurred in July, with statistical significance (amplitude=0.23, phase=1.2, low point=7.2). The UPD group showed the peak birth month in spring; however, this result was not statistically significant (χ(2)=3.39, P=0.1836). CONCLUSION Correlation with birth seasonality was identified in a deletion group of Korean PWS patients. Further studies are required to identify the mechanism related to seasonal effects of environmental factors on microdeletion on chromosome 15.
Collapse
Affiliation(s)
- Aram Yang
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yeon Hee Lee
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Soon Young Nam
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yu Ju Jeong
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yechan Kyung
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Rimm Huh
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jieun Lee
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Younghee Kwun
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Yoon Cho
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Dong-Kyu Jin
- Department of Pediatics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| |
Collapse
|
9
|
Vergés L, Molina O, Geán E, Vidal F, Blanco J. Deletions and duplications of the 22q11.2 region in spermatozoa from DiGeorge/velocardiofacial fathers. Mol Cytogenet 2014; 7:86. [PMID: 25435913 PMCID: PMC4247602 DOI: 10.1186/s13039-014-0086-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 11/04/2014] [Indexed: 11/12/2022] Open
Abstract
Background DiGeorge/velocardiofacial syndrome (DGS/VCFS) is the most common deletion syndrome in humans. Low copy repeats flanking the 22q11.2 region confer a substrate for non-allelic homologous recombination (NAHR) events leading to rearrangements. This study sought to identify DGS/VCFS fathers with increased susceptibility to deletions and duplications at the 22q11.2 region in spermatozoa and to assess the particular contribution of intra-chromatid and/or inter-chromatid NAHR. Semen samples from nine DGS/VCFS fathers were analyzed by triple-color FISH using a probe combination that discriminated between normal, deleted and duplicated genotypes. Microsatellite analysis were performed in the parents and the affected children to determine the parental origin of the deleted chromosome 22. Results A significant increase in 22q11.2 deletions was observed in the sperm of two out of nine DGS/VCFS fathers (odds ratio 2.03-fold, P < 0.01), and in both cases the deletion in the offspring was transmitted by the father. Patients with significant increases in sperm anomalies presented a disturbed deletion:duplication 1:1 ratio (P < 0.01). Conclusions Altogether, results support that intra-chromatid NAHR is the mechanism responsible for the higher rate of sperm deletions, which is directly related to the transmission of the deleted chromosome 22 to offspring. Accordingly, the screening of sperm anomalies in the 22q11.2 region should be taken into account in the genetic counseling of DGS/VCFS families.
Collapse
Affiliation(s)
- Laia Vergés
- Unitat de Biologia Cellular (Facultat de Biociències). Universitat Autònoma de Barcelona, 08193-Bellaterra, Cerdanyola del Vallès, Spain
| | - Oscar Molina
- Unitat de Biologia Cellular (Facultat de Biociències). Universitat Autònoma de Barcelona, 08193-Bellaterra, Cerdanyola del Vallès, Spain ; Current address: Wellcome Trust Center for Cell Biology, University of Edinburgh, Edinburgh, Scotland United Kingdom
| | - Esther Geán
- Secció de Genètica Clínica. Hospital Universitari Sant Joan de Déu, 08950-Esplugues de Llobregat, Barcelona, Spain
| | - Francesca Vidal
- Unitat de Biologia Cellular (Facultat de Biociències). Universitat Autònoma de Barcelona, 08193-Bellaterra, Cerdanyola del Vallès, Spain
| | - Joan Blanco
- Unitat de Biologia Cellular (Facultat de Biociències). Universitat Autònoma de Barcelona, 08193-Bellaterra, Cerdanyola del Vallès, Spain
| |
Collapse
|
10
|
Pires R, Pires LM, Vaz SO, Maciel P, Anjos R, Moniz R, Branco CC, Cabral R, Carreira IM, Mota-Vieira L. Screening of copy number variants in the 22q11.2 region of congenital heart disease patients from the São Miguel Island, Azores, revealed the second patient with a triplication. BMC Genet 2014; 15:115. [PMID: 25376777 PMCID: PMC4228150 DOI: 10.1186/s12863-014-0115-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 10/17/2014] [Indexed: 12/24/2022] Open
Abstract
Background The rearrangements in the 22q11.2 chromosomal region, responsible for the 22q11.2 deletion and microduplication syndromes, are frequently associated with congenital heart disease (CHD). The present work aimed to identify the genetic basis of CHD in 87 patients from the São Miguel Island, Azores, through the detection of copy number variants (CNVs) in the 22q11.2 region. These structural variants were searched using multiplex ligation-dependent probe amplification (MLPA). In patients with CNVs, we additionally performed fluorescent in situ hybridization (FISH) for the assessment of the exact number of 22q11.2 copies among each chromosome, and array comparative genomic hybridization (array-CGH) for the determination of the exact length of CNVs. Results We found that four patients (4.6%; A to D) carried CNVs. Patients A and D, both affected with a ventricular septal defect, carried a de novo 2.5 Mb deletion of the 22q11.2 region, which was probably originated by inter-chromosomal (inter-chromatid) non-allelic homologous recombination (NAHR) events in the regions containing low-copy repeats (LCRs). Patient C, with an atrial septal defect, carried a de novo 2.5 Mb duplication of 22q11.2 region, which could have been probably generated during gametogenesis by NAHR or by unequal crossing-over; additionally, this patient presented a benign 288 Kb duplication, which included the TOP3B gene inherited from her healthy mother. Finally, patient B showed a 3 Mb triplication associated with dysmorphic facial features, cognitive deficit and heart defects, a clinical feature not reported in the only case described so far in the literature. The evaluation of patient B’s parents revealed a 2.5 Mb duplication in her father, suggesting a paternal inheritance with an extra copy. Conclusions This report allowed the identification of rare deletion and microduplication syndromes in Azorean CHD patients. Moreover, we report the second patient with a 22q11.2 triplication, and we suggest that patients with triplications of chromosome 22q11.2, although they share some characteristic features with the deletion and microduplication syndromes, present a more severe phenotype probably due to the major dosage of implicated genes.
Collapse
Affiliation(s)
- Renato Pires
- Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal. .,Centre for Biodiversity, Functional and Integrative Genomics (BioFIG), Faculty of Sciences, University of Lisboa, Lisboa, 1749-016, Portugal.
| | - Luís M Pires
- Cytogenetics and Genomics Laboratory, Faculty of Medicine, University of Coimbra, Coimbra, 3000-354, Portugal.
| | - Sara O Vaz
- Department of Paediatrics, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal.
| | - Paula Maciel
- Department of Paediatrics, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal.
| | - Rui Anjos
- Department of Paediatric Cardiology, Hospital of Santa Cruz, Av. Prof. Dr. Reinaldo dos Santos, Carnaxide, 2790-134, Portugal.
| | - Raquel Moniz
- Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal.
| | - Claudia C Branco
- Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal. .,Centre for Biodiversity, Functional and Integrative Genomics (BioFIG), Faculty of Sciences, University of Lisboa, Lisboa, 1749-016, Portugal. .,Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, Oeiras, 2780-156, Portugal.
| | - Rita Cabral
- Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal.
| | - Isabel M Carreira
- Cytogenetics and Genomics Laboratory, Faculty of Medicine, University of Coimbra, Coimbra, 3000-354, Portugal.
| | - Luisa Mota-Vieira
- Molecular Genetics and Pathology Unit, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Av. D. Manuel I, Ponta Delgada 9500-370, São Miguel Island, Azores, Portugal. .,Centre for Biodiversity, Functional and Integrative Genomics (BioFIG), Faculty of Sciences, University of Lisboa, Lisboa, 1749-016, Portugal. .,Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, Oeiras, 2780-156, Portugal.
| |
Collapse
|
11
|
Ayabe T, Matsubara K, Ogata T, Ayabe A, Murakami N, Nagai T, Fukami M. Birth seasonality in Prader-Willi syndrome resulting from chromosome 15 microdeletion. Am J Med Genet A 2013; 161A:1495-7. [DOI: 10.1002/ajmg.a.35893] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 01/11/2013] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Atsuko Ayabe
- Department of Pediatrics; Dokkyo Medical University Koshigaya Hospital; Koshigaya; Japan
| | | | | | - Maki Fukami
- Department of Molecular Endocrinology; National Research Institute for Child Health and Development; Tokyo; Japan
| |
Collapse
|
12
|
Martínez-Frías M, Martínez-Fernández M. A highly specific coding system for structural chromosomal alterations. Am J Med Genet A 2013; 161A:732-6. [DOI: 10.1002/ajmg.a.35787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 10/30/2012] [Indexed: 11/06/2022]
|
13
|
Fine characterisation of a recombination hotspot at the DPY19L2 locus and resolution of the paradoxical excess of duplications over deletions in the general population. PLoS Genet 2013; 9:e1003363. [PMID: 23555282 PMCID: PMC3605140 DOI: 10.1371/journal.pgen.1003363] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 01/19/2013] [Indexed: 11/19/2022] Open
Abstract
We demonstrated previously that 75% of infertile men with round, acrosomeless spermatozoa (globozoospermia) had a homozygous 200-Kb deletion removing the totality of DPY19L2. We showed that this deletion occurred by Non-Allelic Homologous Recombination (NAHR) between two homologous 28-Kb Low Copy Repeats (LCRs) located on each side of the gene. The accepted NAHR model predicts that inter-chromatid and inter-chromosome NAHR create a deleted and a duplicated recombined allele, while intra-chromatid events only generate deletions. Therefore more deletions are expected to be produced de novo. Surprisingly, array CGH data show that, in the general population, DPY19L2 duplicated alleles are approximately three times as frequent as deleted alleles. In order to shed light on this paradox, we developed a sperm-based assay to measure the de novo rates of deletions and duplications at this locus. As predicted by the NAHR model, we identified an excess of de novo deletions over duplications. We calculated that the excess of de novo deletion was compensated by evolutionary loss, whereas duplications, not subjected to selection, increased gradually. Purifying selection against sterile, homozygous deleted men may be sufficient for this compensation, but heterozygously deleted men might also suffer a small fitness penalty. The recombined alleles were sequenced to pinpoint the localisation of the breakpoints. We analysed a total of 15 homozygous deleted patients and 17 heterozygous individuals carrying either a deletion (n = 4) or a duplication (n = 13). All but two alleles fell within a 1.2-Kb region central to the 28-Kb LCR, indicating that >90% of the NAHR took place in that region. We showed that a PRDM9 13-mer recognition sequence is located right in the centre of that region. Our results therefore strengthen the link between this consensus sequence and the occurrence of NAHR. We demonstrated previously that most men with globozoospermia, who produce only round acrosomeless spermatozoa and are 100% infertile, had a homozygous deletion removing the totality of DPY19L2. We also showed that this deletion occurred by Non-Allelic Homologous Recombination (NAHR). NAHR results in the production of deletions and duplications of regions encompassed by two homologous sequences, normally with a higher occurrence of deletions over duplications. Analysis of public databases at the DPY19L2 locus paradoxically revealed that, in the general population, duplications were approximately three times as frequent as deletions. Analysis of sperm DNA permits us to quantify de novo events that take place during male meiosis. We therefore measured the rates of de novo deletion and duplication in the sperm of three healthy donors. As predicted by the NAHR theoretical model and contrary to the allelic frequency observed in the general population, we identified an approximate 2-fold excess of deletions over duplications. We calculated that the measured rate of de novo deletion was compensated by evolutionary loss, whereas duplications, not subjected to selection, increased gradually. Purifying selection against infertile homozygous deleted men may be sufficient for this compensation, or heterozygously deleted men may also suffer a small fitness penalty.
Collapse
|
14
|
Agergaard P, Olesen C, Østergaard JR, Christiansen M, Sørensen KM. Chromosome 22q11.2 duplication is rare in a population-based cohort of Danish children with cardiovascular malformations. Am J Med Genet A 2012; 158A:509-13. [PMID: 22302736 DOI: 10.1002/ajmg.a.34441] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 11/02/2011] [Indexed: 11/09/2022]
Abstract
The prevalence of the 22q11.2 duplication is unknown in children with cardiovascular malformations (CVMs). As most individuals with the duplication are detected in the search for other conditions, especially the 22q11.2 deletion, CVMs associated with the duplication are subject to referral bias. We circumvented this bias by investigating the prevalence of the 22q11.2 duplication in a population-based cohort of children with CVMs. The study population was defined as children born in 2000-2008, who were registered in the Danish National Patient Registry with a diagnosis of CVM from one of the two national university departments of pediatric cardiology. Sensitive multiplex ligation-dependent probe amplification was performed on dried blood spot samples from each individual's neonatal screening test. The study population consisted of 2,952 children with CVMs, 2,424 of whom were eligible for genetic testing; 13 individuals (0.5% [0.3-0.9%]) carried the duplication. Nine individuals (69%) had not previously been tested for a copy number variation on chromosome 22q11.2 in the clinical setting for children with CVMs. We conclude that 22q11.2 duplication is rare in children with CVMs, and is primarily found in malformations that are also associated with the 22q11.2 deletion.
Collapse
|