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Jiang X, Zhang B, Gou Q, Cai R, Sun C, Li J, Yang N, Wen C. Variations in seminal microbiota and their functional implications in chickens adapted to high-altitude environments. Poult Sci 2024; 103:103932. [PMID: 38972291 PMCID: PMC11263954 DOI: 10.1016/j.psj.2024.103932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/29/2024] [Accepted: 05/29/2024] [Indexed: 07/09/2024] Open
Abstract
Seminal fluid, once believed to be sterile, is now recognized as constituting a complex and dynamic environment inhabited by a diverse community of micro-organisms. However, research on the seminal microbiota in chickens is limited, and microbiota variations among different chicken breeds remain largely unexplored. In this study, we collected semen samples from Beijing You Chicken (BYC) and Tibetan Chicken (TC) and explored the characteristics of the microbiota using 16S rRNA gene sequencing. Additionally, we collected cloacal samples from the TC to control for environmental contamination. The results revealed that the microbial communities in the semen were significantly different from those in the cloaca. Firmicutes and Actinobacteriota were the predominant phyla in BYC and TC semen, respectively, with Lactobacillus and Phyllobacterium being the dominant genera in each group. Additionally, the seminal microbiota of BYC exhibited greater richness and evenness than that of TC. Principal coordinate analysis (PCoA) indicated significant intergroup differences between the seminal microbiotas of BYC and TC. Subsequently, by combining linear discriminant analysis effect size and random forest analyses, we identified Lactobacillus as the predominant microorganism in BYC semen, whereas Phyllobacterium dominated in TC semen. Furthermore, co-occurrence network analysis revealed a more intricate network in the BYC group than in the TC group. Additionally, unique microbial functional characteristics were observed in each breed, with TC exhibiting metabolic features potentially associated with their ability to adapt to high-altitude environments. The results of this study emphasized the unique microbiota present in chicken semen, which may be influenced by genetics and evolutionary history. Significant variations were observed between low-altitude and high-altitude breeds, highlighting the breed-specific implications of the seminal microbiota for reproduction and high-altitude adaptation.
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Affiliation(s)
- Xinwei Jiang
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Boxuan Zhang
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Sanya Institute of China Agricultural University, Hainan, 572025, China
| | - Qinli Gou
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Ronglang Cai
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China
| | - Congjiao Sun
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China; Sanya Institute of China Agricultural University, Hainan, 572025, China
| | - Junying Li
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China; Sanya Institute of China Agricultural University, Hainan, 572025, China
| | - Ning Yang
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China; Sanya Institute of China Agricultural University, Hainan, 572025, China
| | - Chaoliang Wen
- State Key Laboratory of Animal Biotech Breeding and Frontier Science Center for Molecular Design Breeding, China Agricultural University, Beijing, 100193, China; National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193, China; Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China; Sanya Institute of China Agricultural University, Hainan, 572025, China.
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2
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Graham JH, Schlachetzki JCM, Yang X, Breuss MW. Genomic Mosaicism of the Brain: Origin, Impact, and Utility. Neurosci Bull 2024; 40:759-776. [PMID: 37898991 PMCID: PMC11178748 DOI: 10.1007/s12264-023-01124-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 07/16/2023] [Indexed: 10/31/2023] Open
Abstract
Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic mutations. Traditionally, research focused on the impact of genomic mosaicism on clinical phenotype-motivated by its involvement in cancers and overgrowth syndromes. More recently, we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental exposures. Here, we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and homeostasis. Although the field of genomic mosaicism has a rich history, technological advances in the last decade have changed our approaches and greatly improved our knowledge. We will provide current definitions and an overview of contemporary detection approaches for genomic mosaicism. Finally, we will discuss the impact and utility of genomic mosaicism.
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Affiliation(s)
- Jared H Graham
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Aurora, 80045-2581, CO, USA
| | - Johannes C M Schlachetzki
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, 92093-0021, San Diego, CA, USA
| | - Xiaoxu Yang
- Department of Neurosciences, University of California San Diego, La Jolla, 92093-0021, San Diego, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, 92123, CA, USA
| | - Martin W Breuss
- Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Aurora, 80045-2581, CO, USA.
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3
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Zsigmond A, Till Á, Bene J, Czakó M, Mikó A, Hadzsiev K. Case Report of Suspected Gonadal Mosaicism in FOXP1-Related Neurodevelopmental Disorder. Int J Mol Sci 2024; 25:5709. [PMID: 38891897 PMCID: PMC11171548 DOI: 10.3390/ijms25115709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 05/20/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024] Open
Abstract
Heterozygous mutations in the FOXP1 gene (OMIM#605515) are responsible for a well-characterized neurodevelopmental syndrome known as "intellectual developmental disorder with language impairment with or without autistic features" (OMIM#613670) or FOXP1 syndrome for short. The main features of the condition are global developmental delay/intellectual disability; speech impairment in all individuals, regardless of their level of cognitive abilities; behavioral abnormalities; congenital anomalies, including subtle dysmorphic features; and strabismus, brain, cardiac, and urogenital abnormalities. Here, we present two siblings with a de novo heterozygous FOXP1 variant, namely, a four-year-old boy and 14-month-old girl. Both children have significantly delayed early psychomotor development, hypotonia, and very similar, slightly dysmorphic facial features. A lack of expressive speech was the leading symptom in the case of the four-year-old boy. We performed whole-exome sequencing on the male patient, which identified a pathogenic heterozygous c.1541G>A (p.Arg514His) FOXP1 mutation. His sister's targeted mutation analysis also showed the same heterozygous FOXP1 variant. Segregation analysis revealed the de novo origin of the mutation, suggesting the presence of parental gonadal mosaicism. To the best of our knowledge, this is the first report of gonadal mosaicism in FOXP1-related neurodevelopmental disorders in the medical literature.
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Affiliation(s)
- Anna Zsigmond
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
| | - Ágnes Till
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
| | - Judit Bene
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
| | - Márta Czakó
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
| | - Alexandra Mikó
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
- Institute for Translational Medicine, Medical School, University of Pécs, H-7624 Pécs, Hungary
| | - Kinga Hadzsiev
- Department of Medical Genetics, Medical School, University of Pécs, H-7623 Pécs, Hungary; (A.Z.); (Á.T.); (J.B.); (M.C.); (A.M.)
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杨 晓. [Sperm Mosaic Variants and Their Influence on the Offspring]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2024; 55:535-541. [PMID: 38948294 PMCID: PMC11211766 DOI: 10.12182/20240560507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Indexed: 07/02/2024]
Abstract
Genomic mosaicism arising from mosaic variants is a phenomenon that describes the presence of a cell or cell populations with different genome compositions from the germline cells of an individual. It comprises all types of genetic variants. A large proportion of childhood genetic disorders are defined as being de novo, meaning that the disease-causing mutations are only detected in the proband, not in any of the parents. Population studies show that 80% of the de novo mutations arise from the paternal haplotype, that is, from paternal sperm mosaicism. This review provides a summary of the types and detection strategies of sperm mosaicism. In addition, it provides discussions on how recent studies demonstrated that genomic mosaic mutations in parents, especially those in the paternal sperms, could be inherited by the offspring and cause childhood disorders. According to the previous findings of the author's research team, sperm mosaicism derived from early embryogenesis and primordial germ cell stages can explain 5% to 20% of the de novo mutations related to clinical phenotypes and can serve as an important predictor of both rare and complex disorders. Sperm mosaicism shows great potential for clinical genetic diagnosis and consultations. Based on the published literature, the author suggests that, large-scale screening for de novo sperm mosaic mutations and population-based genetic screening should be conducted in future studies, which will greatly enhance the risk assessment in the offspring and effectively improve the genetic health at the population level. Implementation of direct sperm detection for de novo mutations will significantly increase the efficiency of the stratification of patient cohorts and improve recurrence risk assessment for future births. Future research in the field should be focused on the impact of environmental and lifestyle factors on the health of the offspring through sperms and their modeling of mutation signatures. In addition, targeted in vitro modeling of sperm mutations will also be a promising direction.
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Affiliation(s)
- 晓旭 杨
- 犹他大学 (盐湖城 UT 84112)University of Utah, Salt Lake City, UT 84112, USA
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Lecoquierre F, Cassinari K, Drouot N, May A, Fourneaux S, Charbonnier F, Derambure C, Coutant S, Saugier-Veber P, Hoischen A, Charbonnier C, Nicolas G. Assessment of parental mosaicism rates in neurodevelopmental disorders caused by apparent de novo pathogenic variants using deep sequencing. Sci Rep 2024; 14:5289. [PMID: 38438430 PMCID: PMC10912112 DOI: 10.1038/s41598-024-53358-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 01/31/2024] [Indexed: 03/06/2024] Open
Abstract
While de novo variants (DNV) are overall at low risk of recurrence in subsequent pregnancies, a subset is at high risk due to parental mosaicism. Accurately identifying cases of parental mosaicism is therefore important for genetic counseling in clinical care. Some studies have investigated the rate of parental mosaics, but most were either limited by the sensitivity of the techniques (i.e. exome or genome sequencing), or focused on specific types of disease such as epileptic syndromes. This study aimed to determine the proportion of parental mosaicism among the DNV causing neurodevelopmental disorders (NDDs) in a series not enriched in epilepsy syndromes. We collected 189 patients with NDD-associated DNV. We applied a smMIP enrichment method and sequenced parental blood DNA samples to an average depth of 7000x. Power simulation indicated that mosaicism with an allelic fraction of 0.5% would have been detected for 87% of positions with 90% power. We observed seven parental mosaic variants (3.7% of families), of which four (2.1% of families) had an allelic fraction of less than 1%. In total, our study identifies a relatively low proportion of parental mosaicism in NDD-associated DNVs and raises the question of a biological mechanism behind the higher rates of parental mosaicism detected in other studies, particularly those focusing on epileptic syndromes.
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Affiliation(s)
- François Lecoquierre
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France.
- Centre de Ressources Biologiques institutionnel du CHU de Rouen - Biothèque filière génétique, Rouen, France.
| | - Kévin Cassinari
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Nathalie Drouot
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Angèle May
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Steeve Fourneaux
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Francoise Charbonnier
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Celine Derambure
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Sophie Coutant
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Pascale Saugier-Veber
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Alexander Hoischen
- Department of Human Genetics, Radboud University Medical Center, 6525 GA, Nijmegen, The Netherlands
| | - Camille Charbonnier
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
| | - Gaël Nicolas
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and reference center for developmental disorders, F-76000, Rouen, France
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6
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Xu N, Shi W, Cao X, Zhou X, Jin L, Huang HF, Chen S, Xu C. Parental mosaicism detection and preimplantation genetic testing in families with multiple transmissions of de novo mutations. J Med Genet 2023; 60:910-917. [PMID: 36707240 PMCID: PMC10447385 DOI: 10.1136/jmg-2022-108920] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 01/14/2023] [Indexed: 01/28/2023]
Abstract
BACKGROUND De novo mutations (DNMs) are linked with many severe early-onset disorders ranging from rare congenital malformation to intellectual disability. Conventionally, DNMs are considered to have an estimated recurrence rate of 1%. Recently, studies have revealed a higher prevalence of parental mosaicism, leading to a greater recurrence risk, resulting in a second child harbouring the same DNM as a previous child. METHODS In this study, we included 10 families with DNMs leading to adverse pregnancy outcomes. DNA was extracted from tissue samples, including parental peripheral blood, parental saliva and paternal sperm. High-throughput sequencing was used to screen for parental mosaicism with a depth of more than 5000× on average and a variant allele fraction (VAF) detection limit of 0.5%. RESULTS The presence of mosaicism was detected in sperms in two families, with VAFs of 2.8% and 2.5%, respectively. Both families have a history of multiple adverse pregnancies and DNMs shared by siblings. Preimplantation genetic testing (PGT) and prenatal diagnosis were performed in one family, thereby preventing the reoccurrence of DNMs. CONCLUSION This study is the first to report the successful implementation of PGT for monogenic/single gene defects in the parental mosaicism family. Our study suggests that mosaic detection of paternal sperm is warranted in families with recurrent DNMs leading to adverse pregnancy outcomes, and PGT can effectively block the transmission of the pathogenic mutation.
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Affiliation(s)
- Naixin Xu
- International Peace Maternity and Child Health Hospital, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
| | - Weihui Shi
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
| | - Xianling Cao
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
| | - Xuanyou Zhou
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
| | - Li Jin
- International Peace Maternity and Child Health Hospital, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
| | - He-Feng Huang
- International Peace Maternity and Child Health Hospital, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
- Research Units of Embryo Original Diseases, Chinese Academy of Medical Sciences (No. 2019RU056), Shanghai, China
| | - Songchang Chen
- International Peace Maternity and Child Health Hospital, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
| | - Chenming Xu
- International Peace Maternity and Child Health Hospital, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
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7
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Yang X, Xu X, Breuss MW, Antaki D, Ball LL, Chung C, Shen J, Li C, George RD, Wang Y, Bae T, Cheng Y, Abyzov A, Wei L, Alexandrov LB, Sebat JL, Gleeson JG. Control-independent mosaic single nucleotide variant detection with DeepMosaic. Nat Biotechnol 2023; 41:870-877. [PMID: 36593400 PMCID: PMC10314968 DOI: 10.1038/s41587-022-01559-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 10/10/2022] [Indexed: 01/04/2023]
Abstract
Mosaic variants (MVs) reflect mutagenic processes during embryonic development and environmental exposure, accumulate with aging and underlie diseases such as cancer and autism. The detection of noncancer MVs has been computationally challenging due to the sparse representation of nonclonally expanded MVs. Here we present DeepMosaic, combining an image-based visualization module for single nucleotide MVs and a convolutional neural network-based classification module for control-independent MV detection. DeepMosaic was trained on 180,000 simulated or experimentally assessed MVs, and was benchmarked on 619,740 simulated MVs and 530 independent biologically tested MVs from 16 genomes and 181 exomes. DeepMosaic achieved higher accuracy compared with existing methods on biological data, with a sensitivity of 0.78, specificity of 0.83 and positive predictive value of 0.96 on noncancer whole-genome sequencing data, as well as doubling the validation rate over previous best-practice methods on noncancer whole-exome sequencing data (0.43 versus 0.18). DeepMosaic represents an accurate MV classifier for noncancer samples that can be implemented as an alternative or complement to existing methods.
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Affiliation(s)
- Xiaoxu Yang
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA.
| | - Xin Xu
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Martin W Breuss
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
- Department of Pediatrics, Section of Genetics and Metabolism, University of Colorado School of Medicine, Aurora, CO, USA
| | - Danny Antaki
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Laurel L Ball
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Changuk Chung
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Jiawei Shen
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Chen Li
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Renee D George
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Yifan Wang
- Department of Quantitative Health Sciences, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Taejeong Bae
- Department of Quantitative Health Sciences, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Yuhe Cheng
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, USA
- Department of Bioengineering, UC San Diego, La Jolla, CA, USA
- Moores Cancer Center, UC San Diego, La Jolla, CA, USA
| | - Alexej Abyzov
- Department of Quantitative Health Sciences, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Liping Wei
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Ludmil B Alexandrov
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, USA
- Department of Bioengineering, UC San Diego, La Jolla, CA, USA
- Moores Cancer Center, UC San Diego, La Jolla, CA, USA
| | - Jonathan L Sebat
- Beyster Center for Genomics of Psychiatric Diseases, University of California, San Diego, La Jolla, CA, USA
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Joseph G Gleeson
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA.
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8
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Wilson TE, Ahmed S, Higgins J, Salk J, Glover T. svCapture: efficient and specific detection of very low frequency structural variant junctions by error-minimized capture sequencing. NAR Genom Bioinform 2023; 5:lqad042. [PMID: 37181851 PMCID: PMC10167630 DOI: 10.1093/nargab/lqad042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/15/2023] [Accepted: 04/28/2023] [Indexed: 05/16/2023] Open
Abstract
Error-corrected sequencing of genomic targets enriched by probe-based capture has become a standard approach for detecting single-nucleotide variants (SNVs) and small insertion/deletions (indels) present at very low variant allele frequencies. Less attention has been given to comparable strategies for rare structural variant (SV) junctions, where different error mechanisms must be addressed. Working from samples with known SV properties, we demonstrate that duplex sequencing (DuplexSeq), which demands confirmation of variants on both strands of a source DNA molecule, eliminates false SV junctions arising from chimeric PCR. DuplexSeq could not address frequent intermolecular ligation artifacts that arise during Y-adapter addition prior to strand denaturation without requiring multiple source molecules. In contrast, tagmentation libraries coupled with data filtering based on strand family size greatly reduced both artifact classes and enabled efficient and specific detection of single-molecule SV junctions. The throughput of SV capture sequencing (svCapture) and base-level accuracy of DuplexSeq provided detailed views of the microhomology profile and limited occurrence of de novo SNVs near the junctions of hundreds of newly created SVs, suggesting end joining as a possible formation mechanism. The open source svCapture pipeline enables rare SV detection as a routine addition to SNVs/indels in properly prepared capture sequencing libraries.
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Affiliation(s)
- Thomas E Wilson
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Samreen Ahmed
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jake Higgins
- TwinStrand Biosciences Inc., Seattle, WA 98121, USA
| | - Jesse J Salk
- TwinStrand Biosciences Inc., Seattle, WA 98121, USA
| | - Thomas W Glover
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
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9
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Wen Y, Wang J, Zhang Q, Yang X, Wei L, Bao X. MECP2 germline mosaicism plays an important part in the inheritance of Rett syndrome: a study of MECP2 germline mosaicism in males. BMC Med 2023; 21:155. [PMID: 37081442 PMCID: PMC10120091 DOI: 10.1186/s12916-023-02846-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 03/23/2023] [Indexed: 04/22/2023] Open
Abstract
BACKGROUND Germline mosaicisms could be inherited to offspring, which considered as "de novo" in most cases. Paternal germline MECP2 mosaicism has been reported in fathers of girls with Rett syndrome (RTT) previously. For further study, we focused on MECP2 germline mosaicism in males, not only RTT fathers. METHODS Thirty-two fathers of RTT girls with MECP2 pathogenic mutations and twenty-five healthy adult males without history and family history of RTT or other genetic disorders were recruited. Sperm samples were collected and ten MECP2 hotspot mutations were detected by micro-droplet digital PCR (mDDPCR). And routine semen test was performed at the same time if the sample was sufficient. Additionally, blood samples were also detected for those with sperm MECP2 mosaicisms. RESULTS Nine fathers with RTT daughters (28.1%, 9/32) were found to have MECP2 mosaicism in their sperm samples, with the mutant allele fractions (MAFs) ranging from 0.05% to 7.55%. Only one father with MECP2 c.806delG germline mosaicism (MAF 7.55%) was found to have mosaicism in the blood sample, with the MAF was 0.28%. In the group of healthy adult males, MECP2 mosaicism was found in 7 sperm samples (28.0%, 7/25), with the MAFs ranging from 0.05% to 0.18%. None of the healthy adult males with MECP2 germline mosaicisms were found with MECP2 mosaicism in blood samples. There were no statistical differences in age, or the incidence of asthenospermia between fathers with RTT daughters and healthy adult males with MECP2 germline mosaicisms. Additionally, there was no linear correlation between MAFs of MECP2 mosaicisms and the age of males with germline MECP2 mosaicisms. CONCLUSIONS Germline MECP2 mosaicism could be found not only in fathers with RTT daughters but also in healthy adult males without family history of RTT. As germline mosaic mutations may be passed on to offspring which commonly known as "de novo", more attention should be paid to germline mosaicism, especially in families with a proband diagnosed with genetic disorders.
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Affiliation(s)
- Yongxin Wen
- Department of Pediatrics, Peking University First Hospital, Beijing, China
- Department of Pediatric Neurology, Guangdong Women and Children Hospital, Guangzhou, Guangdong Province, China
| | - Jiaping Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Qingping Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiaoxu Yang
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Liping Wei
- Center for Bioinformatics, State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xinhua Bao
- Department of Pediatrics, Peking University First Hospital, Beijing, China.
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10
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Solís-Moruno M, Batlle-Masó L, Bonet N, Aróstegui JI, Casals F. Somatic genetic variation in healthy tissue and non-cancer diseases. Eur J Hum Genet 2023; 31:48-54. [PMID: 36289407 PMCID: PMC9823099 DOI: 10.1038/s41431-022-01213-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 09/19/2022] [Accepted: 10/03/2022] [Indexed: 02/08/2023] Open
Abstract
Somatic genetic variants have been studied for several years mostly concerning cancer, where they contribute to its origin and development. It is also clear that the somatic variants load is greater in aged individuals in comparison to younger ones, pointing to a cause/consequence of the senescence process. More recently, researchers have focused on the role of this type of variation in healthy tissue and its dynamics in cell lineages and different organs. In addition, somatic variants have been described to contribute to monogenic diseases, and the number of evidences of their role in complex disorders is also increasing. Thanks to recent advances in next-generation sequencing technologies, this type of genetic variation can be now more easily studied than in the past, although we still face some important limitations. Novel strategies for sampling, sequencing and filtering are being investigated to detect these variants, although validating them with an orthogonal approach will most likely still be needed. In this review, we aim to update our knowledge of somatic variation detection and its relation to healthy tissue and non-cancer diseases.
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Affiliation(s)
- Manuel Solís-Moruno
- grid.5612.00000 0001 2172 2676Institut de Biologia Evolutiva (CSIC-UPF), Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Doctor Aiguader 88, Barcelona, Spain ,grid.5612.00000 0001 2172 2676Genomics Core Facility, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003 Barcelona, Spain ,grid.410458.c0000 0000 9635 9413Department of Immunology, Hospital Clínic, Barcelona, Spain ,grid.10403.360000000091771775Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Laura Batlle-Masó
- grid.7080.f0000 0001 2296 0625Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital Universitari Vall d’Hebron (HUVH), Vall d’Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Núria Bonet
- grid.5612.00000 0001 2172 2676Genomics Core Facility, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003 Barcelona, Spain
| | - Juan I. Aróstegui
- grid.410458.c0000 0000 9635 9413Department of Immunology, Hospital Clínic, Barcelona, Spain ,grid.10403.360000000091771775Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain ,grid.5841.80000 0004 1937 0247Universitat de Barcelona, Barcelona, Spain
| | - Ferran Casals
- grid.5612.00000 0001 2172 2676Genomics Core Facility, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003 Barcelona, Spain ,grid.5841.80000 0004 1937 0247Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain ,grid.5841.80000 0004 1937 0247Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain
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11
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Cheng H, Shang D, Zhou R. Germline stem cells in human. Signal Transduct Target Ther 2022; 7:345. [PMID: 36184610 PMCID: PMC9527259 DOI: 10.1038/s41392-022-01197-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/06/2022] [Accepted: 09/14/2022] [Indexed: 12/02/2022] Open
Abstract
The germline cells are essential for the propagation of human beings, thus essential for the survival of mankind. The germline stem cells, as a unique cell type, generate various states of germ stem cells and then differentiate into specialized cells, spermatozoa and ova, for producing offspring, while self-renew to generate more stem cells. Abnormal development of germline stem cells often causes severe diseases in humans, including infertility and cancer. Primordial germ cells (PGCs) first emerge during early embryonic development, migrate into the gentile ridge, and then join in the formation of gonads. In males, they differentiate into spermatogonial stem cells, which give rise to spermatozoa via meiosis from the onset of puberty, while in females, the female germline stem cells (FGSCs) retain stemness in the ovary and initiate meiosis to generate oocytes. Primordial germ cell-like cells (PGCLCs) can be induced in vitro from embryonic stem cells or induced pluripotent stem cells. In this review, we focus on current advances in these embryonic and adult germline stem cells, and the induced PGCLCs in humans, provide an overview of molecular mechanisms underlying the development and differentiation of the germline stem cells and outline their physiological functions, pathological implications, and clinical applications.
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Affiliation(s)
- Hanhua Cheng
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, 430072, Wuhan, China.
| | - Dantong Shang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, 430072, Wuhan, China
| | - Rongjia Zhou
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, 430072, Wuhan, China.
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12
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Mohiuddin M, Kooy RF, Pearson CE. De novo mutations, genetic mosaicism and human disease. Front Genet 2022; 13:983668. [PMID: 36226191 PMCID: PMC9550265 DOI: 10.3389/fgene.2022.983668] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 09/08/2022] [Indexed: 11/23/2022] Open
Abstract
Mosaicism—the existence of genetically distinct populations of cells in a particular organism—is an important cause of genetic disease. Mosaicism can appear as de novo DNA mutations, epigenetic alterations of DNA, and chromosomal abnormalities. Neurodevelopmental or neuropsychiatric diseases, including autism—often arise by de novo mutations that usually not present in either of the parents. De novo mutations might occur as early as in the parental germline, during embryonic, fetal development, and/or post-natally, through ageing and life. Mutation timing could lead to mutation burden of less than heterozygosity to approaching homozygosity. Developmental timing of somatic mutation attainment will affect the mutation load and distribution throughout the body. In this review, we discuss the timing of de novo mutations, spanning from mutations in the germ lineage (all ages), to post-zygotic, embryonic, fetal, and post-natal events, through aging to death. These factors can determine the tissue specific distribution and load of de novo mutations, which can affect disease. The disease threshold burden of somatic de novo mutations of a particular gene in any tissue will be important to define.
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Affiliation(s)
- Mohiuddin Mohiuddin
- Program of Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- *Correspondence: Mohiuddin Mohiuddin, ; Christopher E. Pearson,
| | - R. Frank Kooy
- Department of Medical Genetics, University of Antwerp, Edegem, Belgium
| | - Christopher E. Pearson
- Program of Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
- *Correspondence: Mohiuddin Mohiuddin, ; Christopher E. Pearson,
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13
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Pan J, Li J, Chen S, Xu C, Huang H, Jin L. Living birth following preimplantation genetic testing for monogenic disorders to prevent low-level germline mosaicism related Nicolaides–Baraitser syndrome. Front Genet 2022; 13:989041. [PMID: 36160002 PMCID: PMC9500527 DOI: 10.3389/fgene.2022.989041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Objective: Paternal sperm mosaicism has few consequences for fathers for mutations being restricted to sperm. However, it could potentially underlie severe sporadic disease in their offspring. Here, we present a live birth of a female infant from a father with low-level sperm DNA mosaicism achieved via preimplantation genetic testing for monogenic disorders (PGT-M).Methods: A couple with the father carrying sperm DNA mosaicism received standard in vitro fertilization treatment, with intracytoplasmic sperm injection, embryo biopsy, polymerase chain reaction, and DNA analysis. Only one unaffected embryo was transferred to the uterine cavity. Amniocentesis was performed at the 16th week of gestation by copy-number variation-sequencing, karyotyping, and Sanger sequencing.Results: Eight surviving embryos were biopsied during the blastocyst stage. Karyomapping and Sanger sequencing were applied to detect the euploidy and paternal mutation. After performing PGT-M, followed by successful pregnancy, the prenatal genetic diagnoses revealed that the fetus was unaffected, and one healthy girl was born.Conclusion: This is the first reported live birth with unaffected children achieved via PGT for a low-level germline mosaicism father. It not only opens the possibility of preventing the recurrent monogenic disease of children among gonadal mosaicism families but also alerts clinicians to consider gonadal mosaicism as the source of DMNs.
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Affiliation(s)
- Jiexue Pan
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Research Units of Embryo Original Diseases, Chinese Academy of Medical Sciences, Shanghai, China
| | - Jie Li
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Songchang Chen
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Chenming Xu
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
| | - Hefeng Huang
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Embryo Original Diseases, Shanghai, China
- Research Units of Embryo Original Diseases, Chinese Academy of Medical Sciences, Shanghai, China
- *Correspondence: Hefeng Huang, ; Li Jin,
| | - Li Jin
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, China
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, China
- *Correspondence: Hefeng Huang, ; Li Jin,
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14
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Breuss MW, Yang X, Stanley V, McEvoy-Venneri J, Xu X, Morales AJ, Gleeson JG. Unbiased mosaic variant assessment in sperm: a cohort study to test predictability of transmission. eLife 2022; 11:78459. [PMID: 35787314 PMCID: PMC9255958 DOI: 10.7554/elife.78459] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/19/2022] [Indexed: 01/23/2023] Open
Abstract
Background: De novo mutations underlie individually rare but collectively common pediatric congenital disorders. Some of these mutations can also be detected in tissues and from cells in a parent, where their abundance and tissue distribution can be measured. We previously reported that a subset of these mutations is detectable in sperm from the father, predicted to impact the health of offspring. Methods: As a cohort study, in three independent couples undergoing in vitro fertilization, we first identified male gonadal mosaicism through deep whole genome sequencing. We then confirmed variants and assessed their transmission to preimplantation blastocysts (32 total) through targeted ultra-deep genotyping. Results: Across 55 gonadal mosaic variants, 15 were transmitted to blastocysts for a total of 19 transmission events. This represented an overall predictable but slight undertransmission based upon the measured mutational abundance in sperm. We replicated this conclusion in an independent, previously published family-based cohort. Conclusions: Unbiased preimplantation genetic testing for gonadal mosaicism may represent a feasible approach to reduce the transmission of potentially harmful de novo mutations. This—in turn—could help to reduce their impact on miscarriages and pediatric disease. Funding: No external funding was received for this work.
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Affiliation(s)
- Martin W Breuss
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States.,Department of Pediatrics, Section of Clinical Genetics and Metabolism, University of Colorado School of Medicine, Aurora, United States
| | - Xiaoxu Yang
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Valentina Stanley
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Jennifer McEvoy-Venneri
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Xin Xu
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | | | - Joseph G Gleeson
- Rady Children's Institute for Genomic Medicine, San Diego, United States.,Department of Neurosciences, University of California, San Diego, La Jolla, United States
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15
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Frisk S, Wachtmeister A, Laurell T, Lindstrand A, Jäntti N, Malmgren H, Lagerstedt-Robinson K, Tesi B, Taylan F, Nordgren A. Detection of germline mosaicism in fathers of children with intellectual disability syndromes caused by de novo variants. Mol Genet Genomic Med 2022; 10:e1880. [PMID: 35118825 PMCID: PMC9000944 DOI: 10.1002/mgg3.1880] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/21/2021] [Accepted: 01/14/2022] [Indexed: 12/03/2022] Open
Abstract
Background De novo variants are a common cause to rare intellectual disability syndromes, associated with low recurrence risk. However, when such variants occur pre‐zygotically in parental germ cells, the recurrence risk might be higher. Still, the recurrence risk estimates are mainly based on empirical data and the prevalence of germline mosaicism is often unknown. Methods To establish the prevalence of mosaicism in parents of children with intellectual disability syndromes caused by de novo variants, we performed droplet digital PCR on DNA extracted from blood (43 trios), and sperm (31 fathers). Results We detected low‐level mosaicism in sperm‐derived DNA but not in blood in the father of a child with Kleefstra syndrome caused by an EHMT1 variant. Additionally, we found a higher level of paternal mosaicism in sperm compared to blood in the father of a child with Gillespie syndrome caused by an ITPR1 variant. Conclusion By employing droplet digital PCR, we detected paternal germline mosaicism in two intellectual disability syndromes. In both cases, the mosaicism level was higher in sperm than blood, indicating that analysis of blood alone may underestimate germline mosaicism. Therefore, sperm analysis can be clinically useful to establish the recurrence risk for parents and improve genetic counselling.
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Affiliation(s)
- Sofia Frisk
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Alexandra Wachtmeister
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Tobias Laurell
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Hand Surgery, Södersjukhuset, Stockholm, Sweden
| | - Anna Lindstrand
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Nina Jäntti
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Helena Malmgren
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Kristina Lagerstedt-Robinson
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Bianca Tesi
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Fulya Taylan
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Ann Nordgren
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
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