copy number variation of genes
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The genetic correlates of extreme impulsive violence are poorly understood, and there have been no studies that have systematically characterized a large group of affected individuals both clinically and genetically. We performed a genome-wide rare copy number variant (CNV) analysis in 281 males from four Czech prisons who met strict clinical criteria for extreme impulsive violence. Inclusion criteria included age ≥ 18 years, an ICD-10 diagnosis of Dissocial Personality Disorder, and the absence of an organic brain disorder. Participants underwent a structured psychiatric assessment to diagnose extreme impulsive violence and then provided a blood sample for genetic analysis. DNA was genotyped and CNVs were identified using Illumina HumanOmni2.5 single-nucleotide polymorphism array platform. Comparing with 10851 external population controls, we identified 828 rare CNVs (frequency ≤ 0.1% among control samples) in 264 participants. The CNVs impacted 754 genes, with 124 genes impacted more than once (2-25 times). Many of these genes are associated with autosomal dominant or X-linked disorders affecting adult behavior, cognition, learning, intelligence, specifically expressed in the brain and relevant to synapses, neurodevelopment, neurodegeneration, obesity and neuropsychiatric phenotypes. Specifically, we identified 31 CNVs of clinical relevance in 31 individuals, 59 likely clinically relevant CNVs in 49 individuals, and 17 recurrent CNVs in 65 individuals. Thus, 123 of 281 (44%) individuals had one to several rare CNVs that were indirectly or directly relevant to impulsive violence. Extreme impulsive violence is genetically heterogeneous and genomic analysis is likely required to identify, further research and specifically treat the causes in affected individuals.
- MeSH
- asociální osobnost genetika MeSH
- dospělí MeSH
- impulzivní chování * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- násilí * MeSH
- senioři MeSH
- variabilita počtu kopií segmentů DNA * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
INTRODUCTION: Gnetophytes, comprising the genera Ephedra, Gnetum and Welwitschia, are an understudied, enigmatic lineage of gymnosperms with a controversial phylogenetic relationship to other seed plants. Here we examined the organization of ribosomal DNA (rDNA) across representative species. METHODS: We applied high-throughput sequencing approaches to isolate and reconstruct rDNA units and to determine their intragenomic homogeneity. In addition, fluorescent in situ hybridization and Southern blot hybridization techniques were used to reveal the chromosome and genomic organization of rDNA. KEY RESULTS: The 5S and 35S rRNA genes were separate (S-type) in Gnetum montanum, Gnetum gnemon and Welwitschia mirabilis and linked (L-type) in Ephedra altissima. There was considerable variability in 5S rDNA abundance, ranging from as few as ~4000 (W. mirabilis) to >100 000 (G. montanum) copies. A similar large variation was also observed in 5S rDNA locus numbers (two to 16 sites per diploid cell). 5S rRNA pseudogenes were interspersed between functional genes forming a single unit in E. altissima and G. montanum. Their copy number was comparable or even higher than that of functional 5S rRNA genes. In E. altissima internal transcribed spacers of 35S rDNA were long and intrinsically repetitive while in G. montanum and W. mirabilis they were short without the subrepeats. CONCLUSIONS: Gnetophytes are distinct from other gymnosperms and angiosperms as they display surprisingly large variability in rDNA organization and rDNA copy and locus numbers between genera, with no relationship between copy numbers and genome sizes apparent. Concerted evolution of 5S rDNA units seems to have led to the amplification of 5S pseudogenes in both G. montanum and E. altissima. Evolutionary patterns of rDNA show both gymnosperm and angiosperm features underlining the diversity of the group.
We evaluated copy number variation (CNV) for four genes in rat strains differing in nervous system excitability. rpl13a copy number is significantly reduced in hippocampus and bone marrow in rats with a high excitability threshold and stress. The observed phenomenon may be associated with a role for rpl13a in lipid metabolism.
- MeSH
- hipokampus metabolismus fyziologie MeSH
- kortikální excitabilita genetika fyziologie MeSH
- kostní dřeň metabolismus fyziologie MeSH
- krysa rodu rattus MeSH
- nervový systém - fyziologické jevy genetika MeSH
- ribozomální proteiny genetika MeSH
- variabilita počtu kopií segmentů DNA genetika MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The ability of plants to identify an optimal flowering time is critical for ensuring the production of viable seeds. The main environmental factors that influence the flowering time include the ambient temperature and day length. In wheat, the ability to assess the day length is controlled by photoperiod (Ppd) genes. Due to its allohexaploid nature, bread wheat carries the following three Ppd-1 genes: Ppd-A1, Ppd-B1 and Ppd-D1. While photoperiod (in)sensitivity controlled by Ppd-A1 and Ppd-D1 is mainly determined by sequence changes in the promoter region, the impact of the Ppd-B1 alleles on the heading time has been linked to changes in the copy numbers (and possibly their methylation status) and sequence changes in the promoter region. Here, we report that plants with the same number of Ppd-B1 copies may have different heading times. Differences were observed among F7 lines derived from crossing two spring hexaploid wheat varieties. Several lines carrying three copies of Ppd-B1 headed 16 days later than other plants in the population with the same number of gene copies. This effect was associated with changes in the gene expression level and methylation of the Ppd-B1 gene.
Východiska: Přestože je bevacizumab prvním biologickým léčivem schváleným pro léčbu metastatického kolorektálního karcinomu (mCRC), neexistuje žádný zavedený DNA biomarker, který by zlepšil jeho účinnost a personalizoval léčbu. Materiál a metody: Sledováno bylo 30 pacientů s mCRC na terapii bevacizumabem (15 s dobrou odpovědí a 15 se špatnou odpovědí) z Fakultní nemocnice Olomouc. Pro analýzu variací v počtu kopií genů (copy number variation – CNV) byly použity vzorky FFPE a OncoScan FFPE Assay Kit, který zachycuje přibližně 900 nádorových genů. Výsledky: Ve skupině dobře reagujících pacientů bylo jako potenciálně významné pozitivní prediktivní nádorové biomarkery léčby bevacizumabem identifikováno 102 genů (klasifikovaných jako ATPázy, typ AAA, neuronální přenos signálu, regulace transkripce a domény typu PH superior). Ve špatně reagující skupině bylo identifikováno 74 potenciálně negativních prediktivních genů (klasifikovaných jako galektiny, signální dráha Jak-STAT, kaskáda MAPK, diferenciace a doména asociovaná s F-boxem). Závěr: V pilotní studii jsme našli slibné biomarkery variace počtu kopií odpovědi na bevacizumab v FFPE vzorcích nádorů pacientů s mCRC. Validační fáze by měla být zaměřena zejména na geny spojené s angiogenezí (AGRN, MAPK8, ARHGAP22, LGALS13, LGALS4, ZFP36 a MYC), tumorigenezí (DVL1) a proliferací tumoru (IFNL1, IFNL2, IFNL3, MAP3K10 a MAP4K1).
Background: Despite bevacizumab being the first biological agent approved for the treatment of metastatic colorectal cancer (mCRC), there is not any established DNA biomarker to improve its efficacy and personalize the treatment. Materials and methods: Thirty patients with mCRC on bevacizumab therapy (15 with a good response and 15 with a poor response) from the University Hospital Olomouc were followed. Formalin-fixed paraffin-embedded (FFPE) samples were used for copy number variation (CNV) analysis using the OncoScan FFPE Assay Kit in order to capture approx. 900 tumor genes. Results: In the group of good responding patients, 102 genes (classified as ATPases, type AAA, neuronal signal transmission, regulation of transcription, and superior domain PH type), potentially significant positive predictive tumor biomarkers of bevacizumab treatment, were found. In the poorly responding group, 74 potentially negative predictive genes (classified as galectines, Jak-STAT signalling pathway, MAPK cascade, differentiation, and F-box associated domain) were identified. Conclusion: In the pilot study, we found promising copy number variation biomarkers of bevacizumab response in FFPE samples of mCRC patients. The validation phase should be focused especially on the genes associated with angiogenesis (AGRN, MAPK8, ARHGAP22, LGALS13, LGALS4, ZFP36, and MYC), tumorigenesis (DVL1), and tumor proliferation (IFNL1, IFNL2, IFNL3, MAP3K10, and MAP4K1).
- MeSH
- bevacizumab aplikace a dávkování terapeutické užití MeSH
- kolorektální nádory * diagnóza farmakoterapie genetika patologie MeSH
- lidé MeSH
- metastázy nádorů farmakoterapie MeSH
- mutační analýza DNA metody MeSH
- nádorové biomarkery analýza genetika MeSH
- pilotní projekty MeSH
- protinádorové látky imunologicky aktivní aplikace a dávkování terapeutické užití MeSH
- variabilita počtu kopií segmentů DNA MeSH
- Check Tag
- lidé MeSH
Transcriptome sequencing (RNA-seq) is widely used to detect gene rearrangements and quantitate gene expression in acute lymphoblastic leukemia (ALL), but its utility and accuracy in identifying copy number variations (CNVs) has not been well described. CNV information inferred from RNA-seq can be highly informative to guide disease classification and risk stratification in ALL due to the high incidence of aneuploid subtypes within this disease. Here we describe RNAseqCNV, a method to detect large scale CNVs from RNA-seq data. We used models based on normalized gene expression and minor allele frequency to classify arm level CNVs with high accuracy in ALL (99.1% overall and 98.3% for non-diploid chromosome arms, respectively), and the models were further validated with excellent performance in acute myeloid leukemia (accuracy 99.8% overall and 99.4% for non-diploid chromosome arms). RNAseqCNV outperforms alternative RNA-seq based algorithms in calling CNVs in the ALL dataset, especially in samples with a high proportion of CNVs. The CNV calls were highly concordant with DNA-based CNV results and more reliable than conventional cytogenetic-based karyotypes. RNAseqCNV provides a method to robustly identify copy number alterations in the absence of DNA-based analyses, further enhancing the utility of RNA-seq to classify ALL subtype.
- MeSH
- algoritmy MeSH
- karyotypizace MeSH
- lidé MeSH
- sekvenování transkriptomu MeSH
- variabilita počtu kopií segmentů DNA * genetika MeSH
- vysoce účinné nukleotidové sekvenování * metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
BACKGROUND: The incidence of squamous cell carcinoma of the oral tongue (SCCOT) is increasing in people under age 40. There is an urgent need to identify prognostic markers that help identify young SCCOT patients with poor prognosis in order to select these for individualized treatment. MATERIALS AND METHODS: To identify genetic markers that can serve as prognostic markers for young SCCOT patients, we first investigated four young (≤40 years) and five elderly patients (≥50 years) using global RNA sequencing and whole-exome sequencing. Next, we combined our data with data on SCCOT from the cancer genome atlas (TCGA), giving a total of 16 young and 104 elderly, to explore the correlations between genomic variations and clinical outcomes. RESULTS: In agreement with previous studies, we found that SCCOT from young and elderly patients was transcriptomically and also genomically similar with no significant differences regarding cancer driver genes, germline predisposition genes, or the burden of somatic single nucleotide variations (SNVs). However, a disparate copy number variation (CNV) was found in young patients with distinct clinical outcome. Combined with data from TCGA, we found that the overall survival was significantly better in young patients with low-CNV (n = 5) compared to high-CNV (n = 11) burden (P = 0.044). CONCLUSIONS: Copy number variation burden is a useful single prognostic marker for SCCOT from young, but not elderly, patients. CNV burden thus holds promise to form an important contribution when selecting suitable treatment protocols for young patients with SCCOT.
- MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- míra přežití MeSH
- mladý dospělý MeSH
- nádorové biomarkery * MeSH
- nádory jazyka diagnóza genetika mortalita MeSH
- prognóza MeSH
- sekvenování exomu MeSH
- senioři MeSH
- spinocelulární karcinom diagnóza genetika mortalita MeSH
- variabilita počtu kopií segmentů DNA * MeSH
- věkové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Mitochondrial disorders are caused by defects in mitochondrial or nuclear DNA. Although the existence of large deletions in mitochondrial DNA (mtDNA) is well known, deletions affecting whole genes are not commonly described in patients with mitochondrial disorders. Based on the results of whole-genome analyses, copy number variations (CNVs) occur frequently in the human genome and may overlap with many genes associated with clinical phenotypes. We report the discovery of two large heterozygous CNVs on 22q13.33 in two patients with mitochondrial disorders. The first patient harboured a novel point mutation c.667G>A (p.D223N) in the SCO2 gene in combination with a paternally inherited 87-kb deletion. As hypertrophic cardiomyopathy (HCMP) was not documented in the patient, this observation prompted us to compare his clinical features with all 44 reported SCO2 patients in the literature. Surprisingly, the review shows that HCMP was present in only about 50% of the SCO2 patients with non-neonatal onset. In the second patient, who had mitochondrial neurogastrointestinal encephalopathy (MNGIE), a maternally inherited 175-kb deletion and the paternally inherited point mutation c.261G>T (p.E87D) in the TYMP gene were identified.
- MeSH
- bodová mutace * MeSH
- dítě MeSH
- familiární hypertrofická kardiomyopatie diagnóza genetika MeSH
- kojenec MeSH
- lidé MeSH
- lidské chromozomy, pár 22 genetika MeSH
- mitochondriální encefalomyopatie diagnóza genetika MeSH
- mitochondriální proteiny genetika MeSH
- střevní pseudoobstrukce diagnóza genetika MeSH
- thymidinfosforylasa genetika MeSH
- transportní proteiny genetika MeSH
- variabilita počtu kopií segmentů DNA * MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- práce podpořená grantem MeSH
Long transgenes are often used in mammalian genetics, e.g., to rescue mutations in large genes. In the course of experiments addressing the genetic basis of hybrid sterility caused by meiotic defects in mice bearing different alleles of Prdm9, we discovered that introduction of copy-number variation (CNV) via two independent insertions of long transgenes containing incomplete Prdm9 decreased testicular weight and epididymal sperm count. Transgenic animals displayed increased occurrence of seminiferous tubules with apoptotic cells at 18 days postpartum (dpp) corresponding to late meiotic prophase I, but not at 21 dpp. We hypothesized that long transgene insertions could cause asynapsis, but the immunocytochemical data revealed that the adult transgenic testes carried a similar percentage of asynaptic pachytene spermatocytes as the controls. These transgenic spermatocytes displayed less crossovers but similar numbers of unrepaired meiotic breaks. Despite slightly increased frequency of metaphase I spermatocytes with univalent chromosome(s) and reduced numbers of metaphase II spermatocytes, cytological studies did not reveal increased apoptosis in tubules containing the metaphase spermatocytes, but found an increased percentage of tubules carrying apoptotic spermatids. Sperm counts of subfertile animals inversely correlated with the transcription levels of the Psmb1 gene encoded within these two transgenes. The effect of the transgenes was dependent on sex and genetic background. Our results imply that the fertility of transgenic hybrid animals is not compromised by the impaired meiotic synapsis of homologous chromosomes, but can be negatively influenced by the increased expression of the introduced genes.
- MeSH
- apoptóza genetika MeSH
- dvouřetězcové zlomy DNA MeSH
- fertilita genetika MeSH
- genetické pozadí MeSH
- kontrolní body buněčného cyklu genetika MeSH
- myši MeSH
- pachytenní stadium genetika MeSH
- počet spermií MeSH
- spermatocyty metabolismus MeSH
- testis anatomie a histologie metabolismus MeSH
- transgeny * MeSH
- variabilita počtu kopií segmentů DNA * MeSH
- velikost orgánu MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Eligibility to anti-HER2 therapy for breast tumors strictly depends on demonstrating HER2 overexpression (by immunohistochemistry) or HER2 gene amplification by in situ hybridization (ISH), usually defined by the ratio of HER2 gene to chromosome 17 centromere (CEP17) copies. However, the CEP17 copy number increase (CNI) has been proven responsible for misleading HER2 FISH results and recent small cohort studies suggest that chromosome 17 polysomy is actually very rare. Here we investigated by FISH the frequency of true chromosome 17 polysomy in a consecutive cohort of 5,477 invasive breast cancer patients. We evaluated and selected the LSI 17p11.2 probe for chromosome 17 enumeration on a training cohort of 67 breast cancer samples (CEP17 ≥ 2.5). LSI 17p11.2 was used in the 297/5,477 patients from the validation cohort displaying CEP17 CNI (CEP17 ≥ 3.0). Using HER2/17p11.2 scoring criteria, 37.3%/1.5% patients initially classified as equivocal/non-amplified were reclassified as amplified. For a more accurate assessment of chromosome 17 and ploidy in the samples, we tested six markers located on chromosome 17 and centromeric regions of chromosome 8 (CEP8) and 11 (CEP11) in 67 patients with CEP17 and LSI 17p11.2 CNI. True polysomy (hyperdiploidy) according to these markers was found in 0.48% of cases (24/5,020). CEP8 and CEP11 CNI (≥3.0) was more frequent in the hyperdiploid than CEP17 non-polysomic group (55.6% vs. 6.1% and 25% vs. 2.3%, respectively). Our results suggest that chromosome 17 polysomy is a rare event found in <1% breast cancer cases and that polysomy of other chromosomes frequently occurs with chromosome 17 polysomy.
