Ciele: Analýza prenatálnych vzoriek za obdobie 2015–2020. Porovnanie miery detekcie klinicky relevantných variant cytogenetickou analýzou karyotypu a cytogenomickými metódami MLPA (Multiplex Ligation-Depent Probe Amplification) a mikročipmi (CMA – chromosomal microarray). Súbor a metodika: Analyzovaných bolo 1 029 prenatálnych vzoriek cytogenetickým hodnotením karyotypu (n = 1 029), cytogenomickými metódami MLPA (n = 144) a CMA (n = 111). Všetky nebalansované zmeny boli potvrdené metódou MLPA alebo CMA. Výsledky: Z analyzovaného súboru plodov, po odčítaní aneuploidií – 107 (10,40 %, n = 1 029), bolo analýzou karyotypu zachytených 22 štruktúrnych aberácií (2,39 %, n = 922) – deväť nebalansovaných zmien (0,98 %), 10 balansovaných zmien (1,08 %), jeden prípad nejasnej mozaiky (0,09 %), jeden prípad prítomnosti marker chromozómu (0,09 %) a jeden prípad diskordancie pohlavia (0,09 %). U 255 vzoriek s fyziologickým karyotypom indikovaných k cytogenomickému vyšetreniu bolo zachytených celkom osem (7,21 %, n = 111) patologických variant metódou CMA. Metódou MLPA bolo z týchto ôsmich patogénnych variant zachytených päť (3,47 %, n = 144). Celkový záchyt patogénnych variant metódami MLPA a CMA vrátane konfirmačných vyšetrení patologického karyotypu je 14 (5,14 %) a 17 (6,25 %) (n = 272). Záchyt patologických variant v skupine s izolovanými poruchami bol nižší než v skupine s mnohopočetnými poruchami (5,08 vs. 21,42 %). Záver: Potvrdila sa vyššia úspešnosť záchytu patologických variant so zmenou v počte kópií, metódou CMA než MLPA.
Objective: Analysis of prenatal samples from 2015 to 2020. Comparison detection rates of clinically relevant variants by cytogenetic karyotype analysis and cytogenomic MLPA (Multiplex Ligation-Depent Probe Amplification) and microarray methods (CMA – chromosomal microarray). Material and method: 1,029 prenatal samples were analyzed by cytogenetic karyotyping (N = 1,029), cytogenomic methods – MLPA (N = 144) and CMA (N = 111). All unbalanced changes were confirmed by MLPA or CMA. Results: From the analyzed set of fetuses, after subtraction of aneuploidies – 107 (10.40%, N = 1,029), 22 structural aberrations (2.39%, N = 922) – nine unbalanced changes (0.98%), 10 balanced changes (1.08%), one case of unclear mosaicism (0.09%), one case of presence of a marker chromosome (0.09%) and one case of sex discordance (0.09%) – were detected by karyotype analysis. A total of eight (7.21%, N = 111) pathological variants were detected by CMA in 255 samples with physiological karyotype indicated for cytogenomic examination. Five (3.47%, N = 144) of eight pathogenic variants were detected by MLPA method. The total capture of pathogenic variants by MLPA and CMA methods was 14 (5.14%) and 17 (6.25%) (N = 272), including confirmatory pathological karyotype testing. Detection of pathological variants in the isolated disorders group was lower than in the multiple disorders group (5.08 vs. 21.42%). Conclusion: A higher success rate for the detection of pathological copy number variation variants by the microarray method than by the MLPA method was confirmed.
- MeSH
- Clinical Studies as Topic MeSH
- Humans MeSH
- Microarray Analysis methods MeSH
- Mosaicism MeSH
- Multiplex Polymerase Chain Reaction methods MeSH
- Fetus MeSH
- Prenatal Diagnosis * MeSH
- Pregnancy MeSH
- DNA Copy Number Variations MeSH
- Congenital Abnormalities * diagnosis genetics MeSH
- Check Tag
- Humans MeSH
- Pregnancy MeSH
- Female MeSH
OBJECTIVES: The term "copy number variation/variant" (CNV) denotes a DNA sequence with a magnitude of 1 kb at least which is differently represented among individuals based on its deletion or duplication. Since 2008, multiple studies have reported copy number variations in schizophrenia, and they seem to fill in a gap in our knowledge on the genetic background of schizophrenia. The aim of this review is to sum up the current findings related to CNVs in schizophrenia in order to facilitate further research. METHODS: We searched the PubMed computer database using the key words "schizophrenia AND CNVs" on 26th October 2011. Out of 91 obtained results, we selected the references based on their relevance. RESULTS: The CNVs at genome loci 1q21.1, 2p16.3, 3q29, 15q11.2, 15q13.3, 16p13.1 and 22q11.2 were associated with schizophrenia most frequently. The data provide evidence for low prevalent, but highly penetrant CNVs associated with schizophrenia. CNV deletions show higher penetrance than duplications. Larger CNVs often have higher penetrance than smaller CNVs. Although the vast majority of CNVs are inherited, CNVs that have newly occurred as de novo mutations have more readily been implicated in schizophrenia. De novo CNVs may be responsible for the presence of schizophrenia in only one of the two monozygotic twins, who otherwise have identical genomes. CONCLUSION: Identifying CNVs in schizophrenia can lead to changes in the treatment and genetic counselling. Our knowledge on the genetic background of neurodevelopmental disorders may also reduce stigma in schizophrenia.
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
- Antisocial Personality Disorder genetics MeSH
- Adult MeSH
- Impulsive Behavior * MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Violence * MeSH
- Aged MeSH
- DNA Copy Number Variations * MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Male MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
INTRODUCTION: Next-generation sequencing is now used on a routine basis for molecular testing but studies on copy-number variant (CNV) detection from next-generation sequencing data are underrepresented. Utilizing an existing whole-exome sequencing (WES) dataset, we sought to investigate the contribution of rare CNVs to the genetic causality of dystonia. METHODS: The CNV read-depth analysis tool ExomeDepth was applied to the exome sequences of 953 unrelated patients with dystonia (600 with isolated dystonia and 353 with combined dystonia; 33% with additional neurological involvement). We prioritized rare CNVs that affected known disease genes and/or were known to be associated with defined microdeletion/microduplication syndromes. Pathogenicity assessment of CNVs was based on recently published standards of the American College of Medical Genetics and Genomics and the Clinical Genome Resource. RESULTS: We identified pathogenic or likely pathogenic CNVs in 14 of 953 patients (1.5%). Of the 14 different CNVs, 12 were deletions and 2 were duplications, ranging in predicted size from 124bp to 17 Mb. Within the deletion intervals, BRPF1, CHD8, DJ1, EFTUD2, FGF14, GCH1, PANK2, SGCE, UBE3A, VPS16, WARS2, and WDR45 were determined as the most clinically relevant genes. The duplications involved chromosomal regions 6q21-q22 and 15q11-q13. CNV analysis increased the diagnostic yield in the total cohort from 18.4% to 19.8%, as compared to the assessment of single-nucleotide variants and small insertions and deletions alone. CONCLUSIONS: WES-based CNV analysis in dystonia is feasible, increases the diagnostic yield, and should be combined with the assessment of single-nucleotide variants and small insertions and deletions.
- MeSH
- Adult MeSH
- Dystonic Disorders diagnosis genetics MeSH
- Dystonia diagnosis genetics MeSH
- Cohort Studies MeSH
- Humans MeSH
- Exome Sequencing * MeSH
- DNA Copy Number Variations * genetics MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't 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.
OBJECTIVE: Recent studies have integrated copy number variant (CNV) and gene analysis using target enrichment. Here, we transferred this concept to our routine genetics laboratory, which is not linked to centralized non-invasive prenatal testing (NIPT) facilities. METHOD: From a cohort of 100 pregnant women, 22 were selected for the analysis of maternal genomic DNA (gDNA) along with fetal cell-free DNA. Using targeted enrichment, 135 genes were analyzed, combined with aberrations of chromosomes 21, 18, 13, X, and Y. The data were subjected to specificity and sensitivity analyses, and correlated with the results from invasive testing methods. RESULTS: The sensitivity/specificity was determined for the CNV analysis of chromosomes: 21 (80%/75%), 18 (-/82%), 13 (100%/67%), and Y (100%/100%). The gene detection was valid for maternal gDNA. However, for cell-free fetal DNA, it was not possible to determine the boundary between an artifact and a real sequence variant. CONCLUSION: The target enrichment method combining CNV and gene detection seems feasible in a regular laboratory. However, this method can only be responsibly optimized with a sufficient number of controls and further validation on a strong bioinformatic background. The present results showed that NIPT should be performed in specialized centers, and that its introduction to isolated laboratories may not provide valid data.
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
- Hippocampus metabolism physiology MeSH
- Cortical Excitability genetics physiology MeSH
- Bone Marrow metabolism physiology MeSH
- Rats MeSH
- Nervous System Physiological Phenomena genetics MeSH
- Ribosomal Proteins genetics MeSH
- DNA Copy Number Variations genetics MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article 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.
The effects of air pollution on men's reproductive health can be monitored by evaluating semen quality and sperm DNA damage. We used real-time PCR to analyse the effects of air pollution on sperm mitochondrial DNA copy number (mtDNAcn) and deletion (mtDNAdel) rates in semen samples collected from 54 men in two seasons with different levels of industrial and traffic air pollution. MtDNAdel rates were significantly higher following the high exposure period and were positively correlated with mtDNAcn. However, we did not find any difference in mtDNAcn between the two seasons. MtDNAcn was positively correlated with the DNA fragmentation index and the rates of sperm with chromatin condensation defects, previously assessed by sperm chromatin structure assay, and negatively correlated with sperm concentration, progressive motility, viability, and normal morphology. This indicates that mtDNAcn is more closely associated with male fertility than mtDNAdel rates. In contrast, mtDNAdel might be a more sensitive biomarker of air pollution exposure in urban industrial environments.
- MeSH
- Semen Analysis * MeSH
- Chromatin MeSH
- Humans MeSH
- DNA, Mitochondrial genetics MeSH
- Sperm Motility MeSH
- Spermatozoa MeSH
- DNA Copy Number Variations MeSH
- Air Pollution * adverse effects MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Monoclonal gammopathy of undetermined significance (MGUS) is a benign condition with an approximate 1% annual risk of symptomatic plasma cell disorder development, mostly to multiple myeloma (MM). We performed genomewide screening of copy-number alterations (CNAs) in 90 MGUS and 33 MM patients using high-density DNA microarrays. We identified CNAs in a smaller proportion of MGUS (65.6%) than in MM (100.0%, P = 1.31 × 10(-5) ) and showed median number of CNAs is lower in MGUS (3, range 0-22) than in MM (13, range 4-38, P = 1.82 × 10(-10) ). In the MGUS cohort, the most frequent losses were located at 1p (5.6%), 6q (6.7%), 13q (30.0%), 14q (14.4%), 16q (8.9%), 21q (5.6%), and gains at 1q (23.3%), 2p (6.7%), 6p (13.3%), and Xq (7.8%). Hyperdiploidy was detected in 38.9% of MGUS cases, and the most frequent whole chromosome gains were 3 (25.6%), 5 (23.3%), 9 (37.8%), 15 (23.3%), and 19 (32.2%). We also identified CNAs such as 1p, 6q, 8p, 12p, 13q, 16q losses, 1q gain and hypodiploidy, which are potentially associated with an adverse prognosis in MGUS. In summary, we showed that MGUS is similar to MM in that it is a genetically heterogeneous disorder, but overall cytogenetic instability is lower than in MM, which confirms that genetic abnormalities play important role in monoclonal gammopathies.
- MeSH
- Genome-Wide Association Study * MeSH
- Chromosome Aberrations MeSH
- Genomics * methods MeSH
- Humans MeSH
- Multiple Myeloma diagnosis genetics MeSH
- Monoclonal Gammopathy of Undetermined Significance diagnosis genetics MeSH
- Genomic Instability MeSH
- Disease Progression MeSH
- Comparative Genomic Hybridization MeSH
- DNA Copy Number Variations * MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
