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Раздел 6. Наследственные заболевания и врожденные пороки развития
in one patient each. Reciprocal reading by long-distance inverse PCR also disclosed KMT2A fusions with PITPNA in one patient, with LOC100132273 in another patient, and with DNA sequences not compatible with any gene in three patients. The most common KMT2A breakpoint region was intron/exon 9 (3/8 patients), followed by intron/exon 11 and 10. Finally, multicolor banding revealed breakpoints in other chromosomes whose biological and prognostic implications remain to be determined. We conclude that the combination of molecular techniques used in this study can efficiently identify KMT2A fusion partners in complex pediatric acute leukemia karyotypes.
COMPARATIVE ANALYSIS OF INDIVIDUAL CHROMOSOME INVOLVEMENT IN MICRONUCLEI INDUCED BY MITOMYCIN C AND BLEOMYCIN IN HUMAN LEUKOCYTES
Hovhannisyan G.1, Aroutiounian R.1, Babayan N.1,2, Harutyunyan T.1, Liehr T.3
'Department of Genetics and Cytology, Faculty of Biology, Yerevan State University, Yerevan, Armenia; 2Institute of Molecular Biology, National Academy of Sciences, Yerevan, Armenia;
3Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Jena, Germany
Micronucleus (MN) assay is a well standardized approach for evaluation of clastogenic/aneugenic effects of mutagens. Fluorescence in situ hybridization (FISH) is successfully used to characterize the chromosomal content of MN. However, the relationships between nuclear positioning, length, and gene density of individual chromosomes and their involvement in MN induced by different mutagens have not been clearly defined. Chromosomal content of MN was characterized in human leukocytes treated with mitomycin C (MMC) and bleomycin (BLM) by FISH using centromeric (cep) and whole-chromosome painting (wcp) probes. Involvement of chromosomes 8, 15 and 20 in MMC-induced and chromosomes 1, 9 and 16 in BLM-induced MN was studied, and correlated with chromosome size, gene density and interphase position. The results obtained were analyzed together with previous own data on the frequencies of inclusion of chromosomes 3, 4, 6, 7, 9, 16, 17, 18, and X in MMC-induced MN. It could be shown that MMC- and BLM-induced MN could contain material derived from all chromosomes investigated. Involvement of whole chromosomes 8, 15 and 20 in MMC-induced MN negatively correlated with gene density; however, analysis together with earlier studied chromosomes did not confirm this correlation. Inclusion of chromosomes 8, 15 and 20 in MMC-induced MN does not depend on their size and interphase position; the same result was found for the twelve overall analyzed chromosomes. In BLM-treated cells significant correlation between frequencies of involvement of chromosomes 1, 9 and 16 in MN and their size was found.
Our results clearly revealed that BLM differs from MMC with respect to the distribution of induced chromosome damage and MN formation. Thus, DNA-damaging agents with diverse mechanism of action induce qualitatively different MN with regard to their chromosomal composition. Also this study demonstrates the utility of combined sequential application of cep and wcp probes for efficient detection of MN chromosomal content in terms of centric and acentric fragments.
CONSTITUTIONAL GENOME AND CHROMOSOME INSTABILITIES IN THE AUTISTIC BRAIN
lourov I. Y.1-2-3, Vorsanova S.G.1-2-4, Liehr T.5, Zelenova M.A.1-2-4, Kurinnaia O.S.1-2-4, Vasin K.S.1-2-4, Kolotii A.D.1-2, Korostelev S.A.6, Yurov Y.B.1-2-4 'Mental Health Research Center, Moscow, Russian Federation;
2Research and Clinical Institute for Pediatrics named after Y. E. Veltishev at the Pirogov Russian National Research Medical University, Ministry of Health, Moscow, Russian Federation;
3Department of Medical Genetics, Russian Medical Academy of Postgraduate Education, Ministry of Health, Moscow, Russian Federation;
"Moscow State University of Psychology and Education,
Moscow, Russian Federation;
5Institute of Human Genetics, Jena, Germany;
6FSBI «Research Centre for Medical Genetics», Moscow,
Russian Federation
Introduction. Chromosome and genome instabilities confined to the human brain are associated with neurological and psychiatric diseases. However, the autistic brain has not been studied in context of genomic copy number variations. Here, we have evaluated copy number variations (CNV) and chromosomal rearrangements in the autistic brain.
Materials and Methods. SNP/oligonucleotide micro-array and FISH were used to evaluate 22 post-mortem brain samples of 12 patients with autism (cerebellum and cerebral cortex). Additionally, an original bioinformat-ics technology to interpret and prioritize CNV was used.
Results. Chromosomal mosaicism for additional chromosome X in a male chromosome complement and mosaic isodicentric chromosome 15 were detected in 2 unrelated samples. This data were confirmed by FISH. A sample exhibited duplication at 20q13.2q13.33 (~10 Mb). Constitutional chromosome instability mimic chromothripsis manifesting as non-mosaic and mosaic multiple CNV (from 7000 to 32100 and from 22 to 61, respectively) was detected in 3 cases. Mean CNV amount in the cerebellum was higher than in the cortex (287.8 vs. 259.7). Finally, all the samples of the autistic brain exhibited an increased background level of chromosome X an-euploidy as to control brain samples addressed previously.
Conclusions. We show that the autistic brain is hallmarked by constitutional genome (chromosome) instabil-
РОССИЙСКИЙ ВЕСТНИК ПЕРИНАТОЛОГИИ И ПЕДИАТРИИ, 4, 2016 ROSSIYSKIY VESTNIK PERINATOLOGY IPEDIATRII, 4, 2016
ИННОВАЦИОННЫЕ ТЕХНОЛОГИИ В ПЕДИАТРИИ И ДЕТСКОЙ ХИРУРГИИ
ity. Additionally, constitutional chromothripsis is shown to affect the brain in a non-malignant disease. Thus, constitutional chromosome instability in the brain is likely to be a mechanism for neuropathology in this devastating neuropsychiatry disease. Supported by the Russian Science Foundation (Grant #14-35-00060).
CYTOGENETICALLY VISIBLE COPY NUMBER VARIATIONS (CG-CNVS) IN BANDING AND MOLECULAR CYTOGENETICS OF HUMAN; ABOUT HETEROMORPHISMS AND EUCHROMATIC VARIANTS Liehr T.
Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Jena, Germany
Copy number variations (CNVs) having no (obvious) clinical effects were rediscovered as major part of human genome in 2004. However, for every cytogeneticist microscopically visible harmless CNVs (CG-CNVs) are well known since decades. Harmless CG-CNVs can be present as heterochromatic or even as euchromatic variants in clinically healthy persons. Here I provide a review on what is known today on the still too little studied harmless human CG-CNVs, point out which can be mixed up with clinically relevant pathological CG-CNVs and shortly discuss that the artificial separation of euchromatic submicroscopic CNVs (MG-CNVs) and euchromatic CG-CNVs is no longer timely. Overall, neither so-called harmless heterochromatic nor so-called harmless euchro-matic CG-CNVs are considered enough in evaluation of routine cytogenetic analysis and reporting. This holds especially true when bearing in mind the so-called two-hit model suggesting that combination of per se harmless CNVs may lead to clinical aberrations if they are present together in one patient.
MYELODYSPLASTIC SYNDROME WITHOUT RING SIDEROBLASTS AND WITH JANUS KINASE 2 GENE MUTATION: AN UNUSUAL CASE REPORT
Ornellas M.H.12, de Franga Silva M.1, Solza C.3, de Lucena Gongalves S.B.S.3, de Almeida L.S.1,2, de Paula Ayres Silva J.4, Seixas T.L.5, Bastos E.F.5,6, Liehr T.7, Alves G.1,2,8 'Department of Pathology, Laboratory of Circulating Markers, Faculty of Medica Sciences (FCM), Rio de Janeiro, Brazil;
2Graduation Course in Medical Sciences, Faculty of Medica Sciences (FCM), Rio de Janeiro, Brazil; 3Department of Haematology, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil;
"Department of Pathology, Oswaldo Cruz Institute (IOC), Ministry of Health, Rio de Janeiro, Brazil; 'Cytogenetics Laboratory, Faculty of Medical Sciences, Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil;
•Department of Medical Genetic, Fernandes Figueira
Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil;
'University Clinic Jena, Friedrich Schiller University, Institute of Human Genetics, Jena, Germany; 8Research Coordination, National Cancer Institute (INCA), Ministry of Health, Rio de Janeiro, Brazil
Myelodysplastic syndrome (MDS) cases comprise a heterogeneous group of hematological disorders that are characterized by impaired hematopoiesis, with cytopenias of different grades and risk of developing acute myeloid leukemia. MDS may rarely be associated with thrombocy-tosis. In such cases, myelodysplasia and myeloproliferative disorders may overlap, making correct diagnosis difficult. We herein describe a case of MDS with thrombocytosis, Janus kinase 2 gene mutation positive and Perls' staining negative, which was initially classified as essential throm-bocythemia (ET). This case highlights that MDS may be misdiagnosed as ET and inappropriate treatment may be initiated. Therefore, it is crucial to carefully combine all available data on morphology and immunophenotyp-ing, and to perform the necessary molecular, cytogenetic and molecular cytogenetic analyses, in order to correctly diagnose this disease.
A NEW COMPLEX KARYOTYPE IN A UNIQUE DE NOVO MYELODYSPLASTIC SYNDROME CASE INVOLVING TEN CHROMOSOMES AND MONOAL-LELIC LOSS OF TP53
Wafa A.1, As'sad M.1, Liehr T.2, Aljapawe A.3, Al Achkar W.1
'Molecular Biology and Biotechnology Department, Human Genetics Div., Chromosomes lab., Atomic Energy Commission of Syria, Damascus, Syria; Jena University Hospital, Institute of Human Genetics, Jena, Germany;
3Molecular Biology and Biotechnology Department, Mammalians Biology Div., Flow-cytometry Lab., Atomic Energy Commission of Syria, Damascus, Syria
Myelodysplastic syndrome (MDS) is a group of clonal stem cell disorders characterized by cytopenia, dyspla-sia in one or more cell lineages, and ineffective hemato-poiesis. MDS is associated with high risk of progression to acute myeloid leukemia. At initial diagnosis, clonal cytogenetic aberrations are present in 40—70% of patients with de novo (primary) MDS and in 65—95% of patients with therapyassociated ones (t-MDS). Most commonly observed abnormalities present in MDS are monosomy 5 and 7, trisomy 8, deletions of long arm of chromosome 20 as well as complex karyotypes. Loss or gain of chromosomal material is known to be related to disease development and progression. In a de novo adult MDS case banding cytogenetics, refined by array-proven multicolor banding (aMCB) revealed a unique complex karyotype involving ten chromosomes that include del(5q), del(7q), deletions in parts of both chromosomes 10, and a dic(7;17). Interestingly, the dic(7;17) leads to monosomy of the tu-
РОССИЙСКИЙ ВЕСТНИК ПЕРИНАТОЛОГИИ И ПЕДИАТРИИ, 4, 2016 ROSSIYSKIY VESTNIK PERINATOLOGY IPEDIATRII, 4, 2016
