Interstitial deletion 9p23 to 9p11. 1 as sole additional abnormality in a Philadelphia positive chronic myeloid leukemia in blast crisis: a rare event Текст научной статьи по специальности «Биотехнологии в медицине»

Раздел 2 Педиатрия

Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil

3Coordenagao de Pesquisa, Instituto Nacional de Cáncer, Rio de Janeiro, Brasil

4Unidade Técnica de Exposigao Ocupacional, Ambiental e Cáncer, Coordenagao de Prevengao e Vigilancia, Instituto Nacional de Cáncer, Rio de Janeiro, Brasil

5Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Jena, Germany

Brazilian gas station workers are chronically exposed to BTX (benzene, toluene, xylene) during their working time. Acquired chromosomal changes including complex chromosome rearrangements (CCR) were identified in two female attendants by fluorescence in situ hybridization, applying whole chromosome paints for chromosomes 1, 2 and 4. Lower natural killer (NK) cells count was also studied in the corresponding cases, highlighting a rare type of NK (NK-bright) in their peripheral blood cells. It is known that acquired chromosomal aberrations are positively correlated with cancer and reproductive risk. In concordance, lower NK cyto-toxicity increases the risk for cancer, as well. This is the first study providing hints on a possible causative relation of lower NK cytotoxicity and increase rates of chromosomal rearrangements including CCRs. Thus, the early identification of CCRs and blood abnormalities are necessary for effective genetic counseling of workers exposed to BTX, preventing diseases in workers themselves and also in their offspring.

PRENATAL SCREENING OF CYTOGENETIC ANOMALIES - A WESTERN INDIAN EXPERIENCE

Sheth F, Rahman M, Liehr T, Desai M, Patel B, Modi C, Trivedi S, Sheth J.

Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany

Children born with congenital anomalies present a very high rate of perinatal death and neonatal mortality. Cytogenetic analysis is a convincing investigation along with clinical suspicion and biochemical screening tests. The current study was designed to characterize the prevalence and types of chromosomal abnormalities in high risk prenatal samples using different cytogenetic techniques. This study was conducted on a total of 1,728 prenatal samples (1,324 amniotic fluids, 366 chorionic villi and 38 cord blood samples) from 1994 to 2014 at Institute of Human Genetics, Ahmedabad, India. Conventional karyotyping was conducted with GTG-banding. Molecular approaches were used (fluorescence in situ hybridization = FISH and/or array-comparative ge-nomic hybridization = aCGH) when indicated to detect karyotypic abnormalities. Abnormal karyotypes were detected in 125/1,728 (7.2%) cases. Trisomy 21 was the most common abnormality detected in 46 (2.7%) followed by trisomy 18 in 11 (0.6%) and trisomy 13 in 2 (0.1%) samples. Besides, structural abnormalities such as reciprocal and Robertsonian translocation were detected in 20 [1.2%] cases. Turner syndrome was diagnosed in seven (0.4%) cases; in six (0.34%) cases there was an inversion in the Y-chromosome. Hetero-morphic variants were diagnosed in 22 (1.3%) cases. Finally,

small supernumerary marker chromosomes (sSMC) were found in six (0.34%) cases. Conventional GTG-banding along with molecular cytogenetic techniques is useful in detecting genomic alterations and rearrangements. Comprehensive characterization of chromosomal rearrangements like sSMC has the potential to save potentially healthy fetuses from being terminated.

MASKED INV DUP(22)(Q11.23), TETRASOMY 8 AND TRISOMY 19 IN A BLAST CRISIS-CHRONIC MYELOID LEUKEMIA AFTER INTERRUPTED IMA-TINIB-TREATMENT

Wafa A.1, Almedani S.1, Moassass F.1, Liehr T.2, Othman M.A.K.2, Al-Achkar W.1

'Human Genetics Division, Department of Molecular Biology and Biotechnology, Atomic Energy Commission, Damascus, Syria

Jena University Hospital, Institute of Human Genetics, Jena, Germany

The Philadelphia (Ph) chromosome, or derivative chromosome 22 [der(22)], is product of the reciprocal translocation t(9;22). It is the hallmark of chronic myelogenous leukemia (CML). It results in juxtaposition of the 5' part of the BCR gene on chromosome 22 to the 3' part of the ABL1 gene on chromosome 9. During CML progression 60-80% of the cases acquire additional genetic changes. Blast crisis (BC) is characterized by the rapid expansion of a population of differentiation arrested blast cells (myeloid or lymphoid cells population), often presenting with secondary chromosomal abnormalities. Here we report a new CML-BC case with a derivative chromosome 22 inv dup(22)(qll.23) associated with tetrasomy 8 and trisomy 19. These chromosomal aberrations were observed after the patient stopped IM treatment for overall 16 months.A complete cytoge-netic and molecular cytogenetic analysis was performed and application of molecular genetic methods such as reverse transcription polymerase chain reaction (RT-PCR) finally characterized a complex karyotype including an inv dup(22)(q11.23), a del(9)(p24p12) tetrasomy 8 and trisomy 19. Obviously BC resulted in the present patient after to IM treatment was interrupted. The underlying mechanisms and prognostic implications of these cytogenetic abnormalities are discussed. This work was supported by the AECS, in parts by the DAAD.

INTERSTITIAL DELETION 9P23 TO 9P11.1 AS SOLE ADDITIONAL ABNORMALITY IN A PHILADELPHIA POSITIVE CHRONIC MYELOID LEUKEMIA IN BLAST CRISIS: A RARE EVENT

Wafa A.1, Asa'adM.1, Ikhtiar A.2, Liehr T.3, Al-Achkar W.1

1Human Genetics Division, Department of Molecular Biology and Biotechnology, Atomic Energy Commission, Damascus, Syria

2Mammalians Biology Division, Department of Molecular Biology and Biotechnology, Atomic Energy Commission, Damascus, Syria

Jena University Hospital, Institute of Human Genetics, Jena, Germany

РОССИЙСКИЙ ВЕСТНИКПЕРИНАТОЛОГИИ И ПЕДИАТРИИ, 4, 2015

ИННОВАЦИОННЫЕ ТЕХНОЛОГИИ В ПЕДИАТРИИ И ДЕТСКОЙ ХИРУРГИИ

Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by the presence of a derivative chromosome 22 [der(22)] also called Philadelphia chromosome (Ph). The latter is a product of the reciprocal translocation t(9;22)(q34.1;q11.2). During CML progression 60-80% of the cases acquire additional genetic changes. Even though partial chromosome 9 loss is reported in advanced phase-CML, a del(9)(p23p11.1) as sole additional abnormality was not yet seen. A complete cytogenetic and molecular cytogenetic analysis, molecular biology methods such as reverse transcription polymerase chain reaction (RT-PCR), and immunophenotype confirmed the present case to be a CML in blast crisis (BC). It revealed a del(9)(p23p11.1) as sole abnormality besides Ph translocation, which leads to monoallely of tumor suppressor gene CDKN2A (cyclin-dependent kinase inhibitor 2A) pre Imatinib mesylate (IM) treatment. The final karyptype was 46,XY,t(9;22) (q34;q11.2)[11]/46,XY,t(9;22)(q34;q11.2),del(9) (p23p11.1)[9]. The patient did not demonstrate a good response to imatinib treatment. Thus impairment of CDK-N2A gene may be a new adverse prognostic factor in CML. This work was supported by the AECS.

COMPREHENSIVE ANALYSES OF WHITE HANDED GIBBON CHROMOSOMES ENABLES ACCESS TO 92 EVOLUTIONARY CONSERVED BREAKPOINTS COMPARED TO THE HUMAN GENOME

Weise A.1, Kosyakova N.1, Voigt M.1, Aust N.1, Mrasek K.1, Lohmer S.1, Rubtsov N.2, Karamysheva T.2, Trifonov V.3,4, HardekopfD.5, Pekova S.5, Wilhelm K.1, Liehr T.1, Fan X.1 'Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Jena, Germany 2Institute of Cytology and Genetics, Novosibirsk, Russia institute of Molecular and Cellular Biology SB RAS, Russia

"Novosibirsk State University, Novosibirsk, Russia 5Chambon Laboratory for Molecular Diagnostics (member of the Synlab Czech Laboratory Group) Prague, Czech Republic

Gibbon species (Hylobatidae) impress with an unusually high number of numerical and structural chromosomal changes within the family itself as well as compared to other Hominoidea including humans. In former studies applying molecular cytogenetic methods 87 evolutionary conserved breakpoints (ECBs) were reported in the white handed gibbon (Hylobates lar, HLA) with respect to the human genome. To analyze those ECBs in more detail and also to achieve a better understanding of the fast karyotype evolution in Hylobatidae, molecular data for these regions is indispensably necessary. In the present study we obtained whole chromosome specific probes by microdissection of all 21 HLA autosomes, and applied them for array-comparative genomic hybridization; also for selected regions locus-specific DNA probes were used for further molecular cytogenetic characterization. Thus, we could map 5 yet unreported ECBs with respect to the human genome. Additionally in 26 of the 87 previously reported ECBs the present approach enabled a more precise breakpoint map-

ping. Interestingly, a preferred localization of evolutionary conserved breakpoints within segmental duplications, copy number variant regions and fragile sites was observed. This work was supported, in part by DLR RUS 09/008 and the China Scholarship Council.

ЦИТОГЕНЕТИЧЕСКИЙ АНАЛИЗ ХОРИОНА ПРИ НЕРАЗВИВАЮЩЕЙСЯ БЕРЕМЕННОСТИ

Богатырева Е.П., Шиповскова Е.Е.

Волгоградский Областной перинатальный центр №2,

г. Волгоград

Самопроизвольное прерывание беременности обусловлено хромосомными аномалиями, генными мутациями, наследственной предрасположенностью. Целью данного исследования являлось исследование хромосомных аномалий плода при неразвивающей беременности. Материалом для анализа служили клетки 90 самопроизвольно прерванных беременностей сроком до 11 недель. Обследование проводилось цитогенетическим методом. Метафазные пластины получали из клеток цитотрофобласта ворсинчатого хориона прямым методом с последующим окрашиванием QFH/AcD. При анализе выявлена патология в 54 случаях, что составляет 60%, из них 52% плодов женского и 48% мужского пола. Доминирующим типом хромосомных нарушений были численные аномалии

- анеуплоидия и полиплоидия. Их доля составила 93%. Чаще всего выявлялась трисомия хромосомы 16: 13 случаев (24%). Средний возраст женщин с данной патологией плода составлял 32 года. Среди остальных хромосом, задействованных в трисомиях, были 22, 14, 15 по 2 случая; 2, 3, 6, 8, 11, 13, 18 по одному случаю (всего 24%) и 5 случаев (9%) составляли трисомии нескольких хромосом. Средний возраст женщин в этой группе 38,7 лет. На долю анеуплоидий по половым хромосомам пришлось около 20% (11 случаев). В 7 случаях это был кариотип 45,Х; в одном — мозаичный кариотип 45,Х/46,ХХ; в двух — кариотип 45,X/46,XY; в одном

— 47,XXY/46,XY. Средний возраст женщин с такой патологией составлял 26,0 лет. Полиплоидия (трипло-идия) встречалась в 15% (8 случаев). Средний возраст женщин в этой группе был 30 лет. Частота структурных аномалий составила около 7% (4 случая). В одном случае у плода был кариотип 46,XY,t(4;18)(q23;p11.3), в трех случаях — 45,X,t(3;10)(q22;p15)pat; 46,XY,inv(2) (p11.2q12),rob(13;14)(q10;q10),+ 14/45,XY,inv(2) (p11.2q12),der(13;14) (q10;q10); 46,XX,add(11)(q25). В трех случаях носителями сбалансированных перестроек оказались мужчины, причем в случае робертсонов-ской транслокации супруги не были ее носителями, но мужчина оказался носителем инверсии хромосомы 2. Ограничением цитогенетического анализа хориона неразвивающейся беременности является низкая ми-тотическая активность клеток цитотрофобласта: возможно, вследствие того, что фактическая гибель плода произошла за 1-2 недели до взятия материала. В ряде случаев митозов бывает недостаточно, чтобы выявить мозаичный клон, как нормальный, так и патологиче-

РОССИЙСКИЙ ВЕСТНИКПЕРИНАТОЛОГИИ И ПЕДИАТРИИ, 4, 2015