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Yao X, Yao Y, An L, Li X, Bai Y, Cui Y, Wu K. Accumulation and regulation of anthocyanins in white and purple Tibetan Hulless Barley (Hordeum vulgare L. var. nudum Hook. f.) revealed by combined de novo transcriptomics and metabolomics. BMC PLANT BIOLOGY 2022; 22:391. [PMID: 35922757 PMCID: PMC9351122 DOI: 10.1186/s12870-022-03699-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Colored barley, which may have associated human health benefits, is more desirable than the standard white variety, but the metabolites and molecular mechanisms underlying seedcoat coloration remain unclear. RESULTS Here, the development of Tibetan hulless barley was monitored, and 18 biological samples at 3 seedcoat color developmental stages were analyzed by transcriptomic and metabolic assays in Nierumuzha (purple) and Kunlun10 (white). A total of 41 anthocyanin compounds and 4186 DEGs were identified. Then we constructed the proanthocyanin-anthocyanin biosynthesis pathway of Tibetan hulless barley, including 19 genes encoding structural enzymes in 12 classes (PAL, C4H, 4CL, CHS, CHI, F3H, F3'H, DFR, ANS, ANR, GT, and ACT). 11 DEGs other than ANR were significantly upregulated in Nierumuzha as compared to Kunlun10, leading to high levels of 15 anthocyanin compounds in this variety (more than 25 times greater than the contents in Kunlun10). ANR was significantly upregulated in Kunlun10 as compared to Nierumuzha, resulting in higher contents of three anthocyanins compounds (more than 5 times greater than the contents in Nierumuzha). In addition, 22 TFs, including MYBs, bHLHs, NACs, bZips, and WD40s, were significantly positively or negatively correlated with the expression patterns of the structural genes. Moreover, comparisons of homologous gene sequences between the two varieties identified 61 putative SNPs in 13 of 19 structural genes. A nonsense mutation was identified in the coding sequence of the ANS gene in Kunlun10. This mutation might encode a nonfunctional protein, further reducing anthocyanin accumulation in Kunlun10. Then we identified 3 modules were highly specific to the Nierumuzha (purple) using WGCNA. Moreover, 12 DEGs appeared both in the putative proanthocyanin-anthocyanin biosynthesis pathway and the protein co-expression network were obtained and verified. CONCLUSION Our study constructed the proanthocyanin-anthocyanin biosynthesis pathway of Tibetan hulless barley. A series of compounds, structural genes and TFs responsible for the differences between purple and white hulless barley were obtained in this pathway. Our study improves the understanding of the molecular mechanisms of anthocyanin accumulation and biosynthesis in barley seeds. It provides new targets for the genetic improvement of anthocyanin content and a framework for improving the nutritional quality of barley.
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Affiliation(s)
- Xiaohua Yao
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Youhua Yao
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Likun An
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Xin Li
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Yixiong Bai
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Yongmei Cui
- Qinghai University, Xining, 810016, China
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China
| | - Kunlun Wu
- Qinghai University, Xining, 810016, China.
- Qinghai Academy of Agricultural and Forestry Sciences, Xining, 810016, China.
- Qinghai Key Laboratory of Hulless Barley Genetics and Breeding, Xining, 810016, China.
- Qinghai Subcenter of National Hulless Barley Improvement, Xining, 810016, China.
- Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Xining, 810016, China.
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Joshi HR, Hill HR, Asch J, Margraf RL, Coonrod E, Durtschi J, Zhou Q, He X, Voelkerding KV, Kumánovics A. CXXC5 variant in an immunodeficient patient with a progressive loss of hematopoietic cells. J Allergy Clin Immunol 2021; 147:1504-1507.e8. [PMID: 33075407 DOI: 10.1016/j.jaci.2020.09.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 08/28/2020] [Accepted: 09/23/2020] [Indexed: 10/23/2022]
Affiliation(s)
- Hemant R Joshi
- Department of Pathology, University of Utah, Salt Lake City, Utah; ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
| | - Harry R Hill
- Department of Pathology, University of Utah, Salt Lake City, Utah; ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah; Department of Medicine, University of Utah, Salt Lake City, Utah; Department of Pediatrics, University of Utah, Salt Lake City, Utah.
| | - Julie Asch
- Intermountain Blood and Marrow Transplant Program, LDS Hospital, Salt Lake City, Utah
| | - Rebecca L Margraf
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
| | - Emily Coonrod
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
| | - Jacob Durtschi
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
| | - Qin Zhou
- Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Xiao He
- Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Karl V Voelkerding
- Department of Pathology, University of Utah, Salt Lake City, Utah; ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
| | - Attila Kumánovics
- Department of Pathology, University of Utah, Salt Lake City, Utah; ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, Utah
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Kotlarz K, Mielczarek M, Suchocki T, Czech B, Guldbrandtsen B, Szyda J. The application of deep learning for the classification of correct and incorrect SNP genotypes from whole-genome DNA sequencing pipelines. J Appl Genet 2020; 61:607-616. [PMID: 32996082 PMCID: PMC7652806 DOI: 10.1007/s13353-020-00586-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/11/2020] [Accepted: 09/18/2020] [Indexed: 11/18/2022]
Abstract
A downside of next-generation sequencing technology is the high technical error rate. We built a tool, which uses array-based genotype information to classify next-generation sequencing–based SNPs into the correct and the incorrect calls. The deep learning algorithms were implemented via Keras. Several algorithms were tested: (i) the basic, naïve algorithm, (ii) the naïve algorithm modified by pre-imposing different weights on incorrect and correct SNP class in calculating the loss metric and (iii)–(v) the naïve algorithm modified by random re-sampling (with replacement) of the incorrect SNPs to match 30%/60%/100% of the number of correct SNPs. The training data set was composed of data from three bulls and consisted of 2,227,995 correct (97.94%) and 46,920 incorrect SNPs, while the validation data set consisted of data from one bull with 749,506 correct (98.05%) and 14,908 incorrect SNPs. The results showed that for a rare event classification problem, like incorrect SNP detection in NGS data, the most parsimonious naïve model and a model with the weighting of SNP classes provided the best results for the classification of the validation data set. Both classified 19% of truly incorrect SNPs as incorrect and 99% of truly correct SNPs as correct and resulted in the F1 score of 0.21 — the highest among the compared algorithms. We conclude the basic models were less adapted to the specificity of a training data set and thus resulted in better classification of the independent, validation data set, than the other tested models.
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Affiliation(s)
- Krzysztof Kotlarz
- Biostatistics Group, Department of Genetics, Wroclaw University of Environmental and Life Sciences, Kozuchowska 7, 51-631, Wroclaw, Poland
| | - Magda Mielczarek
- Biostatistics Group, Department of Genetics, Wroclaw University of Environmental and Life Sciences, Kozuchowska 7, 51-631, Wroclaw, Poland.,Institute of Animal Breeding, Balice, Poland
| | - Tomasz Suchocki
- Biostatistics Group, Department of Genetics, Wroclaw University of Environmental and Life Sciences, Kozuchowska 7, 51-631, Wroclaw, Poland.,Institute of Animal Breeding, Balice, Poland
| | - Bartosz Czech
- Biostatistics Group, Department of Genetics, Wroclaw University of Environmental and Life Sciences, Kozuchowska 7, 51-631, Wroclaw, Poland
| | - Bernt Guldbrandtsen
- Animal Breeding Group, Department of Animal Sciences, University of Bonn, Bonn, Germany
| | - Joanna Szyda
- Biostatistics Group, Department of Genetics, Wroclaw University of Environmental and Life Sciences, Kozuchowska 7, 51-631, Wroclaw, Poland. .,Institute of Animal Breeding, Balice, Poland.
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Calarco L, Barratt J, Ellis J. Genome Wide Identification of Mutational Hotspots in the Apicomplexan Parasite Neospora caninum and the Implications for Virulence. Genome Biol Evol 2018; 10:2417-2431. [PMID: 30165699 PMCID: PMC6147731 DOI: 10.1093/gbe/evy188] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2018] [Indexed: 01/24/2023] Open
Abstract
Neospora caninum is an apicomplexan parasite responsible for neosporosis, a disease causing hind limb paralysis in dogs and abortion in cattle, resulting in substantial economic losses to beef and dairy industries. Marked differences in pathogenicity exist between N. caninum strains suggesting that intrinsic genetic differences exist between them. These differences likely exist in genes expressed during the tachyzoite lifecycle stage which is responsible for the pathogenesis of neosporosis. An improved understanding of these genetic differences is essential to understanding N. caninum virulence, though such knowledge is scarce. Using a variant detection workflow we compared the tachyzoite transcriptomes of two N. caninum strains with different virulence properties: NC-Liverpool (virulent) and NC-Nowra (avirulent). This workflow identified 3130 SNPs and 6123 indels between the strains, and nine markers capturing 30 variants were Sanger sequenced for both strains. Sequencing of these loci was extended to an additional eight strains and subsequent phylogenetic analysis supported a genetic population structure comprised of two major clades with no geographical segregation. Sequence polymorphisms within coding regions of tachyzoite-associated genes were concentrated on chromosomes XI and XII, with 19 distinct tachyzoite-associated SNP hotspot regions identified within coding regions of the N. caninum nuclear genome. The variants were predominantly located in loci associated with protein binding, protein-protein interactions, transcription, and translation. Furthermore, 468 nonsynonymous SNPs identified within protein-coding genes were associated with protein kinase activity, protein binding, protein phosphorylation, and proteolysis. This work may implicate these processes and the specific proteins involved as novel effectors of N. caninum tachyzoite virulence.
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Affiliation(s)
- Larissa Calarco
- School of Life Sciences, University of Technology Sydney, New South Wales, Australia
| | - Joel Barratt
- School of Life Sciences, University of Technology Sydney, New South Wales, Australia
| | - John Ellis
- School of Life Sciences, University of Technology Sydney, New South Wales, Australia
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Incomplete penetrance for isolated congenital asplenia in humans with mutations in translated and untranslated RPSA exons. Proc Natl Acad Sci U S A 2018; 115:E8007-E8016. [PMID: 30072435 DOI: 10.1073/pnas.1805437115] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Isolated congenital asplenia (ICA) is the only known human developmental defect exclusively affecting a lymphoid organ. In 2013, we showed that private deleterious mutations in the protein-coding region of RPSA, encoding ribosomal protein SA, caused ICA by haploinsufficiency with complete penetrance. We reported seven heterozygous protein-coding mutations in 8 of the 23 kindreds studied, including 6 of the 8 multiplex kindreds. We have since enrolled 33 new kindreds, 5 of which are multiplex. We describe here 11 new heterozygous ICA-causing RPSA protein-coding mutations, and the first two mutations in the 5'-UTR of this gene, which disrupt mRNA splicing. Overall, 40 of the 73 ICA patients (55%) and 23 of the 56 kindreds (41%) carry mutations located in translated or untranslated exons of RPSA. Eleven of the 43 kindreds affected by sporadic disease (26%) carry RPSA mutations, whereas 12 of the 13 multiplex kindreds (92%) carry RPSA mutations. We also report that 6 of 18 (33%) protein-coding mutations and the two (100%) 5'-UTR mutations display incomplete penetrance. Three mutations were identified in two independent kindreds, due to a hotspot or a founder effect. Finally, RPSA ICA-causing mutations were demonstrated to be de novo in 7 of the 23 probands. Mutations in RPSA exons can affect the translated or untranslated regions and can underlie ICA with complete or incomplete penetrance.
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Margraf RL, Durtschi J, Krock B, Newcomb TM, Bonkowsky JL, Voelkerding KV, Bayrak-Toydemir P, Lutz RE, Swoboda KJ. Novel PLP1 Mutations Identified With Next-Generation Sequencing Expand the Spectrum of PLP1-Associated Leukodystrophy Clinical Phenotypes. Child Neurol Open 2018; 5:2329048X18789282. [PMID: 30046645 PMCID: PMC6056774 DOI: 10.1177/2329048x18789282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 06/12/2018] [Indexed: 11/30/2022] Open
Abstract
Next-generation sequencing was performed for 2 families with an undiagnosed neurologic disease. Analysis revealed X-linked mutations in the proteolipid protein 1 (PLP1) gene, which is associated with X-linked Pelizaeus-Merzbacher disease and Spastic Paraplegia type 2. In family A, the novel PLP1 missense mutation c.617T>A (p.M206K) was hemizygous in the 2 affected male children and heterozygous in the mother. In family B, the novel de novoPLP1 frameshift mutation c.359_369del (p.G120fs) was hemizygous in the affected male child. Although PLP1 mutations have been reported to cause an increasingly wide range of phenotypes inclusive of the dystonia, spastic paraparesis, motor neuronopathy, and leukodystrophy observed in our patients, atypical features included the cerebrospinal fluid deficiency of neurotransmitter and pterin metabolites and the delayed appearance of myelin abnormalities on neuroimaging studies. Next-generation sequencing studies provided a diagnosis for these families with complex leukodystrophy disease phenotypes, which expanded the spectrum of PLP1-associated leukodystrophy clinical phenotypes.
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Affiliation(s)
- Rebecca L Margraf
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA
| | - Jacob Durtschi
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA
| | - Bryan Krock
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Tara M Newcomb
- Pediatric Motor Disorders Research Program, Department of Neurology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Joshua L Bonkowsky
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Karl V Voelkerding
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Pinar Bayrak-Toydemir
- ARUP Institute for Clinical and Experimental Pathology, ARUP Laboratories, Salt Lake City, UT, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Richard E Lutz
- Department of Endocrinology, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Genetics, University of Nebraska Medical Center, Omaha, NE, USA
| | - Kathryn J Swoboda
- Pediatric Motor Disorders Research Program, Department of Neurology, University of Utah School of Medicine, Salt Lake City, UT, USA
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, USA
- Department of Neurology, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
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Margraf RL, VanSant-Webb C, Sant D, Carey J, Hanson H, D'Astous J, Viskochil D, Stevenson DA, Mao R. Utilization of Whole-Exome Next-Generation Sequencing Variant Read Frequency for Detection of Lesion-Specific, Somatic Loss of Heterozygosity in a Neurofibromatosis Type 1 Cohort with Tibial Pseudarthrosis. J Mol Diagn 2017; 19:468-474. [PMID: 28433079 DOI: 10.1016/j.jmoldx.2017.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 12/30/2016] [Accepted: 01/30/2017] [Indexed: 10/19/2022] Open
Abstract
A subset of neurofibromatosis type 1 patients develop tibial dysplasia, which can lead to pseudarthrosis. The tissue from the tibial pseudarthrosis region commonly has a somatic second hit in NF1: single-nucleotide variants, small deletions, or loss of heterozygosity (LOH). We used exome next-generation sequencing (NGS) variant frequency data (allelic imbalance analysis) to detect somatic LOH in pseudarthrosis tissue from three individuals with clinically and diagnostically confirmed neurofibromatosis type 1, and verified the results with microarray. The variant files were parsed and plotted using python scripts, and the NGS variant frequencies between the affected tissue and blood sample were compared. Individuals without somatic single-nucleotide variants or small insertions/deletions were tested for somatic LOH using the NGS variant allele frequencies. One individual's NGS data indicated no LOH in chromosome 17. The other two individuals demonstrated somatic LOH inclusive of NF1: one had an LOH region of approximately one million bases and Contra (NGS copy number program) indicated a somatic deletion and the other individual had LOH for most of chromosome 17q and Contra indicated no copy number change (microarray data verified this sample as copy neutral somatic LOH). Both LOH and copy number variation detected by NGS data correlated with microarray data, demonstrating the somatic LOH second hit can be detected directly from the NGS data.
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Affiliation(s)
- Rebecca L Margraf
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah.
| | | | - David Sant
- Miller School of Medicine, University of Miami, Miami, Florida
| | - John Carey
- Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah; Division of Medical Genetics, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, Utah
| | - Heather Hanson
- Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah
| | - Jacques D'Astous
- Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah
| | - Dave Viskochil
- Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah; Division of Medical Genetics, Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, Utah
| | - David A Stevenson
- Division of Medical Genetics, Department of Pediatrics, Stanford University, Stanford, California
| | - Rong Mao
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah; Department of Pathology, School of Medicine, University of Utah, Salt Lake City, Utah
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Sant DW, Margraf RL, Stevenson DA, Grossmann AH, Viskochil DH, Hanson H, Everitt MD, Rios JJ, Elefteriou F, Hennessey T, Mao R. Evaluation of somatic mutations in tibial pseudarthrosis samples in neurofibromatosis type 1. J Med Genet 2015; 52:256-61. [PMID: 25612910 DOI: 10.1136/jmedgenet-2014-102815] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Tibial pseudarthrosis is associated with neurofibromatosis type 1 (NF1) and there is wide clinical variability of the tibial dysplasia in NF1, suggesting the possibility of genetic modifiers. Double inactivation of NF1 is postulated to be necessary for the development of tibial pseudarthrosis, but tissue or cell of origin of the 'second hit' mutation remains unclear. METHODS Exome sequencing of different sections of surgically resected NF1 tibial pseudarthrosis tissue was performed and compared to germline (peripheral blood). RESULTS A germline NF1 splice site mutation (c.61-2A>T, p.L21 M68del) was identified from DNA extracted from peripheral blood. Exome sequencing of DNA extracted from tissue removed during surgery of the tibial pseudarthrosis showed a somatic mutation of NF1 (c.3574G>T, p.E1192*) in the normal germline allele. Further analysis of different regions of the tibial pseudarthrosis sample showed enrichment of the somatic mutation in the soft tissue within the pseudarthrosis site and absence of the somatic mutation in cortical bone. In addition, a germline variant in PTPN11 (c.1658C>T, p.T553M), a gene involved in the RAS signal transduction pathway was identified, although the clinical significance is unknown. CONCLUSIONS Given that the NF1 somatic mutation was primarily detected in the proliferative soft tissue at the pseudarthrosis site, it is likely that the second hit occurred in mesenchymal progenitors from the periosteum. These results are consistent with a defect of differentiation, which may explain why the mutation is found in proliferative cells and not within cortical bone tissue, as the latter by definition contains mostly mature differentiated osteoblasts and osteocytes.
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Affiliation(s)
- David W Sant
- ARUP Laboratories, ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah, USA
| | - Rebecca L Margraf
- ARUP Laboratories, ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah, USA
| | - David A Stevenson
- Department of Pediatrics, Division of Medical Genetics, Stanford University, Stanford, California, USA Departments of Pediatrics, Division of Medical Genetics, University of Utah, School of Medicine, Salt Lake City, Utah, USA Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah, USA
| | - Allie H Grossmann
- ARUP Laboratories, ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah, USA Department of Pathology, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - David H Viskochil
- Departments of Pediatrics, Division of Medical Genetics, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Heather Hanson
- Departments of Pediatrics, Division of Medical Genetics, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Melanie D Everitt
- Departments of Pediatrics, Division of Medical Genetics, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Jonathan J Rios
- Sarah M. and Charles E. Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital for Children, Dallas, Texas, USA Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA Eugene McDermott Center for Human Growth and Development and UT Southwestern Medical Center, Dallas, Texas, USA Department of Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Florent Elefteriou
- Vanderbilt Center for Bone Biology; Vanderbilt University Medical Center, Nashville, Tennessee, USA Departments of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA Departments of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, USA Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Theresa Hennessey
- Shriners Hospital for Children Salt Lake City, Salt Lake City, Utah, USA
| | - Rong Mao
- ARUP Laboratories, ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah, USA Department of Pathology, University of Utah, School of Medicine, Salt Lake City, Utah, USA
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