Análisis citogenético en linfocitos de trabajadores expuestos a radiación ionizante en una unidad de cardiología intervencional de Chile: estudio piloto y revisión de la literatura / Citogenetic effects upon lymphocyes in subjects exposed to ionizing radiadion in an interventional laboratory cardiology: pilot study and literature review

ANTECEDENTES: Un número creciente de artículos está llamando la atención en forma consistente sobre la eventual asociación que existe entre los denominados trabajadores ocupacionalmente expuestos a bajos niveles de radiación ionizante (POEs) y una mayor frecuencia de aberraciones cromosómicas, a nivel Sudamericano estos estudios son escasos. OBJETIVO: Evaluar la frecuencia de aberraciones cromosómicas en linfocitos de sangre periférica de POEs de un hospital y de sujetos sanos. Adicionalmente, se realizó una revisión exhaustiva de los artículos que a la fecha abordaron este tema. MATERIAL Y MÉTODO: Se condujo un análisis citogenético destinado a cuantificar las aberraciones cromosómicas en sangre periférica de linfocitos de 6 POEs de la unidad de Cardiología Intervencional y, como controles, 6 muestras de sujetos de la población general fueron analizadas. RESULTADOS: Se observó un importante contraste en el número de aberraciones cromosómicas presentadas en los POEs versus la población general no expuesta a radiaciones ionizantes, siendo esta de una relación de 6:1, respectivamente. CONCLUSIÓN: Los resultados preliminares indican una mayor frecuencia de aberraciones cromosómicas en los POEs versus la población general, sin embargo, se deberá esperar los resultados de la segunda fase de investigación, donde al ampliar la muestra en análisis se podrán obtener conclusiones estadísticamente significativas.

BACKGROUND: There is growing evidence of an increased number of chromosomes aberrations in subjects exposed to low levels of ionizing radiation (POEs). There are few studies on this subject in Latin America AIM: To evaluate the frequency of chromosome aberrations in lymphocytes obtained from peripheral blood in subjects working in laboratories where low levels of ionizing radiation are present and to compare these findings to those of unexposed subjects. METHODS: A cytogenic analysis to quantify chromosome aberrations was performed in 6 POs subjects from a cardiology invasive laboratory and 6 controls from a general unexposed population. RESULTS: Compared to controls, an approximately 6-fold increase in the number of chromosome aberrations was observed.in subjects exposed to ionizing radiation CONCLUSION: These preliminary results indicate that there is an increased number of chromosome aberrations in subjects exposed to low levels of ionizing radiation, as occurs in people working in a cardiology interventional laboratory. Studies in large numbers of subjects and preferably followed prospectively are needed to evaluate more precisely this effect.

Cytogenetic abnormalities in couples with a history of primary and secondary recurrent miscarriage: a Brazilian Multicentric Study.

Objective: To evaluate the difference between chromosomal abnormalities between the gender of couples affected by Recurrent miscarriage (RM) and if there is an association between previous obstetric history and chromosomal abnormalities of the parents.Methods: Multicenter, retrospective, observational study from seven different RM clinics between 2006 and 2016. We enrolled 707 couples (1014 participants) with a history of RM. We compared the frequency of chromosomal abnormalities between groups of couples with primary and secondary RM and separated between women and their partners. Furthermore, we compared the prevalence of chromosomal abnormalities between groups based on the number of previous spontaneous abortions.Results: The overall prevalence of all cytogenetic abnormalities was 5.59% (n = 1414, women and their partners). Excluding cases of polymorphism and inversion of chromosome 9, which are considered variants of normality, the prevalence in all individuals was 2.26% (n = 32/1414). The comparative analysis of cases of chromosomal abnormalities among couples with primary and secondary RM based on the number of previous miscarriages (PM) revealed a similar frequency between groups. The statistical analysis of the total cases (primary PM + secondary PM) in these three groups were as follows: (a) couple, 2 pm versus 3 pm vs. ≥4 PM, p = .514; (b) women, 2 pm versus 3 pm vs. ≥4 PM, p = .347; and (3) partner, 2 pm versus 3 pm vs. ≥4 PM, p = .959. Chromosomal abnormalities were significantly more prevalent among women than among their partners (6.9 versus 4.2%; p = .027). Moreover, the distribution of leading chromosomal abnormalities among women was different compared with their partners. Among women, we observed these abnormalities in the following frequency order: mosaicism (38.8%), polymorphism (32.6%), translocation (16.3%), and inversion (12.3%). Among their partners, these abnormalities were polymorphism (73.3%), inversion (13.3%), mosaicism (6.7%), and translocation (6.7%).Conclusion: The number of PM and the history of full-term pregnancy does not correlate with an increase or decrease in the prevalence of cytogenetic abnormalities in couples with RM.

Evaluation of genetic damage in pesticides applicators from the province of Córdoba, Argentina.

The impact evaluation of pesticide exposure is conducted using combined data from biomonitoring and environmental monitoring. Damage to the human genome is, probably, the leading cause of chronic-degenerative disorders, reproductive toxicology, and developmental problems. Although the general population is exposed to pesticides, workers in the agrochemical industry and farmers represent a high-risk group due to the occupational and environmental exposure. The aim of this study is to determine whether occupational exposure to agrochemicals in Córdoba (Argentina) constitute a factor of genotoxic damage. The study was conducted in 30 pesticide applicators from the province of Córdoba. Chromosomal aberrations (CAs), micronuclei (MN), and comet assays (CO) were performed. The current study shows that occupational exposure to pesticides increases values of CAs, MN, and DNA fragmentation biomarkers, all indicators of damage to the genetic material. Evidence suggests that chronic exposure to pesticides is a potential risk to workers health.

The most relevant chromosomal abnormalities in the north of Rio Grande do Sul, Brazil: 26 years of cytogenetic analysis.

From 1992 to 2018, cytogenetic analyses were successfully performed to explore the chromosomal abnormalities of 729 patients, who utilised a pioneering counselling service in the city of Passo Fundo in the northern part of the Brazilian state of Rio Grande do Sul. This city is characterised by a large conglomerate of private and public hospitals. A classical cytogenetic analysis and G-banding were performed using the patient samples. Although normal karyotypes were observed for 562 of the cases, 167 individuals evidenced chromosomal alterations. Among those, 110 exhibited numerical alterations (65.86%), 41 demonstrated structural modifications (24.55%) and 16 showed both numerical and structural chromosomal changes (9.58%). This study describes the diversity of the chromosomal alterations in this region, which have not been previously examined. After 26 years of study, the findings are discussed herein in a self-critical form.

Genetic Testing and Pregnancy Outcome Analysis of 362 Fetuses with Congenital Heart Disease Identified by Prenatal Ultrasound / Análise de Teste Genético e de Desfecho da Gestação de 362 Fetos com Cardiopatia Congênita Identificados por Ultrassom Pré-Natal

Abstract Background: Congenital heart defects (CHD), as the most common congenital anomaly, have been reported to be associated with chromosomal abnormalities. Currently, patients with CHD are routinely offered karyotyping and chromosomal microarray (CMA) testing, but the genotype-phenotype relationship has not yet been fully established. Objective: To determine the type and frequency of chromosomal abnormalities in fetuses with CHD and to analyze pregnancy outcomes of fetuses with heart abnormalities caused by different genetic factors. Methods: A total of 362 cases of CHD were enrolled from 2009 to 2016. Detailed ultrasound and laboratory examinations, including karyotyping and CMA, were performed. Outcome was obtained from discharge summaries. Results: Of the 362 fetuses, 220 were found with an isolated CHD, and 142 had CHD with extracardiac anomaly. Among these 362 fetuses, 140 were identified with a genetic cause, including 111 cases with aneuploidy, 10 cases with abnormality of chromosomal structure by karyotyping and 19 cases with pathogenic or likely pathogenic copy-number variations (CNVs) by CMA. The detection rate is close to 38.7%. Only one (identified as trisomy 18 syndrome) in 140 positive cases resulted in perinatal death, with the others being induced. The remaining 222 cases had negative results for both genetic testing and of these cases, 56 resulted in induced labor, and 77 had natural childbirth or caesarean births. The pregnancy outcome of the remaining 89 cases was uncertain. Conclusions: Karyotyping and CMA are effective and accurate prenatal genetic techniques for identifying fetal chromosomal abnormalities associated with cardiac defects, and this can assist clinical doctors to perform appropriate genetic counselling with regard to the etiology and outcome of CHD.

Resumo Fundamento: As cardiopatias congênitas (CCs) são as anomalias congênitas mais comuns, e têm sido associadas a anormalidades cromossômicas. Atualmente, a cariotipagem e a análise cromossômica por microarray (CMA) são oferecidas rotineiramente aos pacientes, mas a relação genótipo-fenótipo ainda não foi totalmente estabelecida. Objetivo: Determinar o tipo e a frequência das anomalias cromossômicas em fetos com CC e analisar os desfechos da gestação de fetos com anormalidades cardíacas causadas por diferentes fatores genéticos. Métodos: No total, foram admitidos 362 casos de CC entre 2009 e 2016. Ultrassonografia e exames laboratoriais detalhados foram realizados, incluindo cariotipagem e CMA. O resultado foi obtido a partir das folhas de epicrise. Resultados: Dos 362 fetos, 220 apresentaram doença coronariana isolada e 142 apresentaram doença coronariana com anomalia extracardíaca. Entre esses 362 fetos, foram identificados 140 com causa genética, incluindo 111 casos com aneuploidia, 10 casos com anormalidade da estrutura cromossômica por cariotipagem e 19 casos com variações no número de cópias (CNVs) patogênicas ou provavelmente patogênicas por CMA. A taxa de detecção é de aproximadamente 38,7%. Apenas um (identificado como síndrome da trissomia do cromossomo 18) em 140 casos positivos resultou em morte perinatal, com as demais sendo induzidas. Os 222 casos restantes tiveram resultados negativos para ambos os testes genéticos e, destes, 56 resultaram em trabalho de parto induzido e 77 tiveram partos naturais ou cesarianas. O desfecho da gravidez dos 89 casos restantes foi incerto. Conclusões: A cariotipagem e a CMA são técnicas genéticas pré-natais eficazes e precisas para a identificação de anomalias cromossômicas fetais associadas a defeitos cardíacos, e isso pode ajudar os médicos a realizar aconselhamento genético adequado com relação à etiologia e ao desfecho das cardiopatias congênitas.

Genetic Testing and Pregnancy Outcome Analysis of 362 Fetuses with Congenital Heart Disease Identified by Prenatal Ultrasound.

BACKGROUND: Congenital heart defects (CHD), as the most common congenital anomaly, have been reported to be associated with chromosomal abnormalities. Currently, patients with CHD are routinely offered karyotyping and chromosomal microarray (CMA) testing, but the genotype-phenotype relationship has not yet been fully established. OBJECTIVE: To determine the type and frequency of chromosomal abnormalities in fetuses with CHD and to analyze pregnancy outcomes of fetuses with heart abnormalities caused by different genetic factors. METHODS: A total of 362 cases of CHD were enrolled from 2009 to 2016. Detailed ultrasound and laboratory examinations, including karyotyping and CMA, were performed. Outcome was obtained from discharge summaries. RESULTS: Of the 362 fetuses, 220 were found with an isolated CHD, and 142 had CHD with extracardiac anomaly. Among these 362 fetuses, 140 were identified with a genetic cause, including 111 cases with aneuploidy, 10 cases with abnormality of chromosomal structure by karyotyping and 19 cases with pathogenic or likely pathogenic copy-number variations (CNVs) by CMA. The detection rate is close to 38.7%. Only one (identified as trisomy 18 syndrome) in 140 positive cases resulted in perinatal death, with the others being induced. The remaining 222 cases had negative results for both genetic testing and of these cases, 56 resulted in induced labor, and 77 had natural childbirth or caesarean births. The pregnancy outcome of the remaining 89 cases was uncertain. CONCLUSIONS: Karyotyping and CMA are effective and accurate prenatal genetic techniques for identifying fetal chromosomal abnormalities associated with cardiac defects, and this can assist clinical doctors to perform appropriate genetic counselling with regard to the etiology and outcome of CHD.

Prevalence of chromosomal aberrations in Argentinean agricultural workers.

Little is known about biosecurity measures and toxic effects during pesticide application in the province of Jujuy, Argentina, particularly concerning the protective measures and mixture of pesticides used by rural workers. We carried out an observational study of agricultural workers from Jujuy (76 exposed subjects and 53 controls) to investigate the prevalence of chromosomal aberrations (CAs) in human lymphocytes as well as the activity level of acetylcholinesterase (AChE) in red blood cell erythrocytes. Whole blood samples (5 mL) were collected in heparinized Vacutainer tubes for cytogenetic analysis and erythrocyte cholinesterase activity determination according to Ellman's method. Cytogenetic results showed a significant CA increase in pesticide-exposed individuals as compared with controls (4.20 ± 0.15 vs. 1.00 ± 0.05, respectively; p < 0.001), suggesting that pesticides are clastogenic agents causing DNA damage. Erythrocyte cholinesterase activity was significantly lower in exposed individuals, evidencing the possible occurrence of perturbations in blood as well as neurotoxicity in pesticide sprayers. These results suggest the need for periodic biomonitoring of these biomarkers together with education and training of occupational workers for the safe application of potentially harmful pesticides.

Frequency of Chromosomal Abnormalities in Products of Conception.

Purpose To describe the frequencies of chromosomal abnormalities found in abortion material, and to observe its correlation to maternal age. Methods A retrospective study was conducted based on data obtained from the databank of a medical genetics laboratory in Belo Horizonte, MG, Brazil. A total of 884 results from products of conception analysis were included, 204 of which were analyzed by cytogenetics, and 680 by molecular biology based on quantitative fluorescence polymerase chain reaction (QF-PCR). The frequency of individual chromosomal aberrations and the relationship between the presence of anomalies and maternal age were also evaluated. Results The conventional cytogenetics technique was able to detect 52% of normal and 48% of abnormal results in the analyzed material. Quantitative fluorescence polymerase chain reaction revealed 60% of normal and 40% of abnormal results from the samples evaluated by this method. The presence of trisomy 15 was detected only by cytogenetics, as it was not included in the QF-PCR routine investigation in the laboratory. A significant increase in abnormal results was observed among women aged 35 years or older compared with younger women (p = 0.02). Conclusion Chromosomal aberrations are still a major cause of spontaneous abortion, and the conventional cytogenetics technique is efficient for miscarriage material analysis, but molecular methods such as QF-PCR are adequate complementary strategies to detect the major chromosomal anomalies, leading to technical reports with reliable results.

Frequency of Chromosomal Abnormalities in Products of Conception / Frequência de anomalias cromossômicas em material de aborto

Abstract Purpose To describe the frequencies of chromosomal abnormalities found in abortion material, and to observe its correlation to maternal age. Methods A retrospective study was conducted based on data obtained from the databank of a medical genetics laboratory in Belo Horizonte, MG, Brazil. A total of 884 results from products of conception analysis were included, 204 of which were analyzed by cytogenetics, and 680bymolecular biology basedon quantitative fluorescence polymerase chain reaction (QF-PCR). The frequency of individual chromosomal aberrations and the relationship between the presence of anomalies and maternal age were also evaluated. Results The conventional cytogenetics technique was able to detect 52% of normal and 48% of abnormal results in the analyzed material. Quantitative fluorescence polymerase chain reaction revealed 60% of normal and 40% of abnormal results from the samples evaluated by this method. The presence of trisomy 15 was detected only by cytogenetics, as it was not included in the QF-PCR routine investigation in the laboratory. A significant increase in abnormal results was observed among women aged 35 years or older compared with younger women (p = 0.02). Conclusion Chromosomal aberrations are still a major cause of spontaneous abortion, and the conventional cytogenetics technique is efficient for miscarriage material analysis, but molecular methods such as QF-PCR are adequate complementary strategies to detect the major chromosomal anomalies, leading to technical reports with reliable results.

Resumo Objetivos Descrever a frequência de anomalias cromossômicas encontradas em material de aborto, e observar se estas estão relacionadas com a idade materna. Métodos Foi realizado um estudo retrospectivo no banco de dados de um laboratório de genética médica em Belo Horizonte, MG. O estudo incluiu 204 resultados avaliados por citogenética, e 680 resultados por biologia molecular baseada em reação em ensaio fluorescente da reação em cadeia da polimerase (QF-PCR), totalizando um número de 884 análises. A frequência de diferentes anomalias cromossômicas e a relação entre a presença de anomalias e a idade materna também foi avaliada. Resultados A citogenética convencional foi capaz de detectar 52% de resultados normais e 48% de resultados anormais no material analisado. A QF-PCR revelou 60% de resultados normais e 40% de anormais nas amostras avaliadas por esta técnica. A presença da trissomia 15 foi detectada por citogenética,mas até então não era incluída na investigação por QF-PCR no laboratório. Umaumento significativo na quantidade de resultados anormais foi observado em mulheres comidade de 35 anos ou mais, quando comparado a mulheres mais jovens (p = 0,02). Conclusão As aberrações cromossômicas são causas importantes de abortos espontâneos, e o estudo citogenético é eficaz para a análise das amostras de material de aborto, mas as técnicas moleculares, como a QF-PCR, representam métodos complementares adequados para detectar as principais anomalias cromossômicas, possibilitando a liberação de laudos com resultados confiáveis.

Frecuencia de aberraciones cromosómicas en pacientes del instituto de genética-UMSA período 2011 – 2015 / Frequency of chromosomopathies at the institute of genetics-UMSA period 2011 -2015

Las anomalías cromosómicas más frecuentes son las aneuploidías, donde resaltan las trisomías autosomas 21, 18, y 13. Son un motivo frecuente de abortos espontáneos, discapacidad intelectual, recién nacidos multimalformados, infertilidad, genitales ambiguos, y juegan un importante rol en la patogenia de enfermedades malignas OBJETIVO: Determinar la frecuencia de pacientes diagnosticados con aberraciones cromosómicas en el Instituto de Genética de la Universidad Mayor de San Andrés entre los años 2011 y 2015. METODOLOGÍA: Estudio de tipo descriptivo, serie de casos. Lugar, Instituto de Genética; La Paz, Bolivia. Período 2011 ­ 2015. Población, pacientes con cariotipo realizado en el Instituto de Genética. RESULTADOS: Se realizaron un total de 1070 estudios citogenéticos, siendo euploides un 69% de los pacientes. Dentro de los cariotipos aneuploides (31%) encontramos 88% de aberraciones cromosómicas constitutivas, y 12% de adquiridas. Las cromosomopatías más frecuentes fueron la trisomía 21, monosomía del X y translocaciones. CONCLUSIONES: Las Aberraciones cromosómicas ocupan un lugar importante en la patología genética humana, representando el 0,4% de los recién nacidos vivos (1). Realizar éste trabajo de investigación nos muestra su existencia en nuestra población, y que no son sólo la letra chica de los libros o casos extraños de película. Es muy necesario tener conocimiento sobre los motivos de solicitud de cariotipo para poder realizar un diagnóstico oportuno, y poder mejorar la calidad de vida del paciente y su familia.

OBJECTIVE: To determine the frequency of patients diagnosed with chromosomal aberrations at the Genetics Institute of the Universidad Mayor de San Andrés between 2011 and 2015. METHODS: Observational, descriptive cross-sectional study. Place, Institute of Genetics; La Paz, Bolivia. Period 2011 - 2015. Population, patients with karyotype performed at the Institute of Genetics. RESULTS: A total of 1070 cytogenetic studies were performed, with 69% of patients being euploid. Within the aneuploid karyotypes (31%) we found 88% constitutive chromosomal aberrations, and 12% acquired. The most frequent chromosomopathies were trisomy 21, X monosomy and translocations. CONCLUSIONS: Chromosomal Aberrations occupy an important place in human genetic pathology, representing 0.4% of the newborns. Performing this research shows us the existence of these pathologies in our population, and that are not only the small print of books or strange cases of film. It is very necessary to have knowledge about chromosomal aberrations in order to make a timely diagnosis and to improve the quality of life of the patient and his family

Male cytogenetic evaluation prior to assisted reproduction procedures performed in Mar del Plata, Argentina.

OBJECTIVE: This paper aimed to estimate the frequency of occurrence and the types of chromosomal abnormalities found in 141 infertile men with abnormal semen parameters. METHODS: the frequency and type of chromosomal abnormalities were determined with male mitotic karyotype analysis from peripheral blood through chromosome banding techniques before assisted reproduction procedures. RESULTS: In this series of 141 infertile men, 19 (13%) had chromosomal anomalies and 35 (25%) had polymorphic variants. The main chromosome abnormalities were reciprocal translocations and marker chromosomes in mosaic. CONCLUSIONS: These results stress the relevance of cytogenetic studies for infertile males as a diagnostic tool and a valuable input in genetic counseling.

Structural chromosomal abnormalities in couples in cases of recurrent spontaneous abortions in Jilin Province, China.

Recurrent spontaneous abortions (RSAs) occur in approximately 15 to 20% of all clinically recognizable pregnancies. Structural chromosome abnormalities result in increased risk of pregnancy loss. Parental chromosomal abnormalities are an important genetic cause of RSAs. Some cytogenetic investigations have been performed in various countries and regions to determine the pattern of chromosomal abnormalities in parents with RSAs. The aim of this study was to report the prevalence and type of structural chromosomal abnormalities in couples in cases of RSAs in Jilin Province, China. The prevalence of structural chromosomal abnormalities in these couples was 2.98%. The number of female carriers with balanced chromosomal aberrations significantly exceeded that of such male carriers, and the ratio of female/male carriers was approximately 2:1. The number of abortions in the case of female carriers was more than that for male carriers before the structural chromosome abnormality was diagnosed. This indicates that genetic counseling for couples with structural chromosomal abnormalities should consider the gender of the carriers.

Array CGH Analysis of Paired Blood and Tumor Samples from Patients with Sporadic Wilms Tumor.

Wilms tumor (WT), the most common cancer of the kidney in infants and children, has a complex etiology that is still poorly understood. Identification of genomic copy number variants (CNV) in tumor genomes provides a better understanding of cancer development which may be useful for diagnosis and therapeutic targets. In paired blood and tumor DNA samples from 14 patients with sporadic WT, analyzed by aCGH, 22% of chromosome abnormalities were novel. All constitutional alterations identified in blood were segmental (in 28.6% of patients) and were also present in the paired tumor samples. Two segmental gains (2p21 and 20q13.3) and one loss (19q13.31) present in blood had not been previously described in WT. We also describe, for the first time, a small, constitutive partial gain of 3p22.1 comprising 2 exons of CTNNB1, a gene associated to WT. Among somatic alterations, novel structural chromosomal abnormalities were found, like gain of 19p13.3 and 20p12.3, and losses of 2p16.1-p15, 4q32.5-q35.1, 4q35.2-q28.1 and 19p13.3. Candidate genes included in these regions might be constitutively (SIX3, SALL4) or somatically (NEK1, PIAS4, BMP2) operational in the development and progression of WT. To our knowledge this is the first report of CNV in paired blood and tumor samples in sporadic WT.

Evaluation of a father and son with atypical chronic myeloid leukemia with SETBP1 mutations and a review of the literature

We report the case of a father and son diagnosed with atypical chronic myeloid leukemia (aCML). Both patients harbored SETBP1 mutations, which are present in 24.3% of aCML patients. Moreover, both shared the variant encoding p.Pro737His, but the aCML severity was greater in the son because of the presence of two other missense mutations causing p.Asp868Asn and p.Ser885Arg alterations. SETBP1 mutations may be associated with an adverse prognosis, so their detection would help in the diagnosis of aCML and the determination of a patient's prognosis.

Antenatal cytogenetic testing in Havana, Cuba.

INTRODUCTION Antenatal cytogenetic testing was started in Havana in 1984, as a diagnostic option for fetal chromosome complement. The techniques applied are amniocyte culture, chorionic villus sampling, cordocentesis and fluorescence in situ hybridization in interphase cells. OBJECTIVE Describe the results of antenatal cytogenetic testing in the cytogenetic laboratory of the Cuba's National Medical Genetics Center in Havana, from 1984 through 2012. METHODS A retrospective descriptive study was carried out of the 22,928 pregnant women who had antenatal testing with conclusive results during the period 1984-2012. Information was obtained from laboratory databases for four antenatal diagnostic techniques. Variables studied were: antenatal diagnostic method, indications for genetic testing, type of chromosomal abnormality detected and couple's decision concerning pregnancy continuation if hereditary disease was diagnosed. Results were reported in absolute numbers and percentages. RESULTS Overall positivity was 2.8% (641 cases). Of the total, 20,565 samples were from amniocyte culture (558 positive cases, 2.7%); 1785 chorionic villus sampling (38 positive, 2.1%); 407 cord blood culture (28 positive, 6.9%); and 171 fluorescence in situ hybridization in interphase cells (17 positive, 9.9%). Advanced maternal age was the predominant indication for amniocyte culture and chorionic villus sampling. Positivity was higher for the two less frequently used methods, cordocentesis (6.9% positivity) and fluorescence in situ hybridization (9.9%). The predominant chromosomal abnormality was Down syndrome, with 45.4% of cases detected (291/641; 279 pure lines and 12 mosaic trisomies), followed by Edward syndrome with 12% (77/641, 71 pure lines and 6 mosaics) and Patau syndrome 4.7% (30/641, 27 pure lines and 3 mosaics). Sexual aneuploidy with pure lines affected 6.9% of cases (44/641) and with mosaicism 4.7% (30/641). Structural chromosomal abnormalities were detected in 22.5% of cases (144/641); of these, 70.8% (102/144) were balanced and 29.2% (42/144) unbalanced. In 78.6% of cases (504/641) with chromosomal abnormalities, whether mosaic or pure, the couple opted to terminate pregnancy. CONCLUSIONS Antenatal cytogenetic testing has helped reduce chromosomal abnormalities, mainly in Havana, and has provided reassurance of chromosomally normal children for couples at high genetic risk. The percentage of continuing pregnancies after a diagnosis of major chromosomal abnormality has been low, supporting evidence of broad population acceptance of abortion as an option when severe genetic abnormalities are present.

[Chromosomal abnormalities in patients from Obstetrics and Gynaecology hospital]. / Anormalidades cromosómicas en pacientes de un hospital de ginecoobstetricia.

BACKGROUND: Chromosomal abnormalities are present in 2-4 % of all newborns, and they cause 20 % of deaths in the first year of life. The estimated prevalence of chromosomal abnormalities is one for each 500-1000 newborns. These abnormalities can be numerical or structural, and they can affect autosomal or sexual chromosomes. They affect from 1 to 3 % of general population, and from 6 to 7 % of individuals with congenital anomalies. METHODS: Descriptive study, which included all the registries of cytogenetic analysis (of adults and newborns) made in a genetic laboratory in a period of 14 years. The prevalence of polymorphisms and chromosomal abnormalities in the patients from the Hospital de Ginecoobstetricia 23, Instituto Mexicano del Seguro Social (Monterrey, Nuevo León) was assessed. RESULTS: Of 4006 cytogenetic studies, 253 (6.3 %) did not show in vitro growth, 2667 (66.5 %) were normal, and 1175 (29.3 %) were abnormal. Of these, 614 (52.2 %) had polymorphisms, and 561 (47.7 %) structural or numerical chromosomal abnormalities. In regards to these chromosomopathies (561), trisomy 21 was observed in 429 (36.5 %); Turner's syndrome, in 84 (7.1 %); trisomy 18, in 57 (4.8 %); and trisomy 13, in 32 (2.7 %). With G-band technique, we found 93 % of in vitro cell growth. CONCLUSIONS: Of these studies, 55 % was performed due to non-numerical abnormalities; 14.4 %, due to structural abnormalities; and the rest, due to polymorphisms.

INTRODUCCIÓN: las anormalidades cromosómicas se presentan en 2 a 4 % de los recién nacidos y causan 20 % de las muertes en el primer año de vida. Su prevalencia es de uno por cada 500 a 1000 recién nacidos vivos. Pueden ser numéricas o estructurales y afectar a los cromosomas autosómicos o sexuales. Se presentan en 1 a 3 % de la población general y en 6 a 7 % de los individuos con anomalías congénitas. MÉTODOS: estudio descriptivo en el que se incluyeron todos los resultados citogenéticos de cariotipos tomados de sangre periférica de adultos y neonatos. Se evaluó la prevalencia de polimorfismos y alteraciones cromosómicas en derechohabientes del Hospital de Ginecoobstetricia 23 del Instituto Mexicano del Seguro Social, en Monterrey, Nuevo León. RESULTADOS: de 4006 estudios citogenéticos, en 253 no se obtuvo crecimiento de linfocitos (6.3 %), 2667 fueron normales (66.5 %) y 1175, anormales (29.3 %); de estos últimos, en 614 (52.2 %) se identificaron polimorfismos cromosómicos y en 561 (47.7 %), aberraciones cromosómicas estructurales o numéricas. De las cromosomopatías (561, 47.7 %), la trisomía 21 se observó en 429 (36.5 %), el síndrome de Turner en 84 (7.1 %), la trisomía 18 en 57 (4.8 %) y la trisomía 13 en 32 (2.7 %). Con la técnica de bandeo G se obtuvo un crecimiento celular in vitro de 93 %. CONCLUSIONES: 55 % de los estudios se realizó por anormalidades diferentes a las numéricas, 14.4 % por alteraciones estructurales y el resto se debió a polimorfismos.

Alterations and chromosomal variants in the Ecuadorian population.

Medical genetics is a field marked by fast progress. Even though it was at one point confined to a group of relatively rare diseases, today it has become a central component in the understanding of disorders and it is the subject of interest for all medical specialties. This paper, shares data on the chromosomal alterations and variations that have been diagnosed in Ecuadorian patients since 1998. A total of 2,636 individual cases have been analyzed by G-banding technique until February 2012. The present work shows this collection of data and the important findings that have appeared throughout these years in hopes that it can contribute to have a deeper understanding of the incidence of chromosomal aberrations and alterations in the Ecuadorian population.

Estudio citogenético en 677 casos de aborto espontáneo / Cytogenetic study of 677 spontaneous abortions

INTRODUCCIÓN: La reproducción humana es un proceso relativamente ineficaz. Los abortos espontáneos ocurren entre el 15 a 20 por ciento de los embarazos clínicamente reconocidos. El impacto emocional se acentúa debido a la falta de diagnóstico. OBJETIVO: Describir la experiencia del Laboratorio de Citogenética de la Clínica Sanatorio Alemán de Concepción e identificarlas alteraciones más frecuentes y su relación estadística con la edad materna. MATERIAL Y MÉTODO: 677 muestras de tejido obtenidas de abortos espontáneos, ocurridos desde julio de1996 a abril de 2009. Es un trabajo de tipo transversal donde las muestras utilizadas son las vellosidades coriónicas, cultivadas en medios estandarizados. RESULTADOS: De las 677 muestras estudiadas, en 259 se obtuvo un cariotipo normal (38,3 por ciento). En 418 muestras se encontraron anomalías cromosómicas, correspondiendo estas a un 61,7 por ciento. Entre los cariogramas alterados se encontraron: 265 trisomías (63,4 por ciento), 83 poliploidías (19,9 por ciento), 48 monosomías (11,5 por ciento) y 22 alteraciones estructurales (5,3 por ciento). La trisomía más frecuente fue la 16 (34,4 por ciento), seguida de la trisomía 21 (13,6 por ciento). Se encontró una relación estadísticamente significativa entre la edad de la madre (> 37 años) y la presencia de alteraciones citogenéticas (p<0,0001). DISCUSIÓN: El 61,7 por ciento de los abortos presentó alguna alteración del cariotipo. La trisomía 16 fue la aberración más frecuente concordando con la literatura. La trisomía 21 se presentó en un 13,6 por ciento siendo más frecuente que lo encontrado en series extranjeras. En el grupo mayor de 37 años existe mayor prevalencia de anomalías cromosómicas siendo estadísticamente significativa (p<0,0001).

INTRODUCCION: The human reproduction is a relatively inefficient process. In the 15 to 20 percent of the pregnancy clinically diagnosticated finish in spontaneous abortions. The great emotional impact, that in many times is worst by the lack of diagnostic. OBJECTIVE: Describe experience of the Cytogenetic Laboratory of Clínica Sanatorio Alemán of Concepción Chile and determinate the frequency of alteration and his relationship with maternal age. MATERIAL AND METHOD: 677 samples of tissue of spontaneous abortions, taked from July, 1996 to April, 2009. It is a descriptive work; the samples are chorionic villous, cultivated in standard solutions. RESULTS: Of 677 samples in 259 was found a normal cariotype (38.3 percent). In 418 was found some type of chromosome aberrations (61.7 percent). The distribution of the abnormal result is the follow: 265 trisomies (63.4 percent), 83 polyploidy (19.8 percent), 48 monosomy (11.5 percent) and 22 abnormalities structures (5.3 percent). Of the trisomies the most recurrent is 16 trisomy with the 34.4 percent, follow by the 21 trisomy with 13.6 percent and the 22 trisomy with 12.8 percent. In the statistic analysis we found a statistically significant relation between the age of the mother (<38 years) and the development of chromosomal alterations (p<0.0001). DISCUSSION: The 61.7 percent of abortions show some cytogenetic alteration. The 16 trisomies were the most frequent, agreeing with the literature. The trisomy 21 was more common than published to date. In older women is most frequent found chromosome aberrations (p<0.0001).

Trisomy 18: experience of a reference hospital from the south of Brazil.

Trisomy 18 is a chromosomal syndrome characterized by a broad clinical picture, as well as a very reserved prognosis. The aim of our study was to verify the clinical characteristics and survival of patients diagnosed in a referral hospital in southern Brazil. Our sample consisted of 31 patients, 22 were female (71%), ages ranging from 1 to 1,395 days (median 14 days). The majority had a single cell lineage with full trisomy of chromosome 18 (94%). Concerning pregnancy complications, pre-eclampsia was the main abnormality described (17%). Fetal ultrasound was performed in 23 cases, and the most frequent abnormalities were polyhydramnios (41%) and intrauterine growth retardation (27%). There were no reports of prenatal identification of the syndrome. Most patients were born by cesarean due to pregnancy and fetal complications and about half of the cases were premature. Congenital heart defects represented the main major malformation observed (94%). Thirty patients (97%) progressed to death (survival ranged from 2 to 780 days, and 87% died within the first 6 months of life). Trisomy 18 is a serious chromosomal disorder with limited survival. Abnormalities of pregnancy appear to be frequent, which can lead to complications for both fetus and mother. The prenatal identification of these patients in our country is still inadequate, resulting in important implications for genetic counseling and management of these patients and their families. And this makes the possibility of interruption of pregnancy, regardless of ethical factors involved, an unlikely option.

The cytogenetic examination as a tool for the diagnosis of chromosomal disorders / Examinación citogenética como herramienta para el diagnóstico de los desórdenes cromosómicos

Clinically significant chromosomal abnormalities occur in about 1 percent of children born alive. The objective of this work was to offer the patients and the families in the community for the service of the Integrated Clinic of Uniara Health (Araraquara and region), the examination of cariotype (cytogenetic study) for confirmation or exclusion of the diagnostic suspicion of chromosomal abnormalities as well as information (genetic counseling) for the prevention of occurrence and/or recurrence of these anomalies. In the period of one year and four months these were carried out in the Integrated Clinic of Uniara Health and directed for the Laboratory of Cytogenetic Human of the same institution in 66 cytogenetic studies. In 44 patients (66.6 percent) the results were normal. In 22 (33.3 percent) examinations, alterations were found, meaning that the respective clinical pictures are decurrent of chromosomic alterations. The first cause within alterations noted was Down syndrome with a total of 15 examinations or 68.1 percent, the second cause of chromosomal anomaly was the Turner syndrome where the most important factor is 45, X, where 2 karyotypes of this type or 9.1 percent were found, syndromes as (Eduards syndrome, Patau syndrome, 3p- syndrome, 4p- syndrome and 6p-syndrome) diagnosed in our laboratory appeared less frequently corresponding to 22.7 percent of the studied anomalies. The work carried out constitutes a necessary diagnosis of the main chromosomal abnormalities through a low cost technique; it can be carried out easily and is reliable, making the cytogenetic examination available to the community and contributing significantly to the quality of life of patients.

Las anormalidades cromosómicas, clínicamente significativas, se presentan en aproximadamente 1 por ciento de los niños nacidos vivos. Este trabajo tiene el objetivo de ofrecer a los pacientes y /o a sus familiares el servicio de la Clínica Integrada de la Salud de Uniara (Araraquara y Región), el examen de cariotipo (estudio citogenético) para la confirmación o la exclusión de sospecha de anomalías cromosomales diagnosticadas, así como otorgar información (consejo genético) para la prevención de las posibles anomalías y /o la repetición de éstas. En un año y cuatro meses fueron realizados 66 estudios de citogenética en la Clínica Integrada de Uniara, dirigida por el Laboratorio de Citogenética Humana de la misma institución. En 44 pacientes (66,6 por ciento) los resultados fueron normales. En 22 (33,3 por ciento) de los exámenes, se encontraron alteraciones, compatibles con alteraciones cromosómicas. La primera causa de anomalías cromosómica fue el síndrome de Down, totalizando 15 exámenes (68,1 por ciento), la segunda causa fue el síndrome de Turner, con dos cariotipos (9,1 por ciento) en la forma más importante 45, X. Por otra parte, se encontró que los síndromes de Eduards, de Patau, 3p-síndrome de Down, síndrome 4p-6p, diagnosticados en nuestro laboratorio, presentaban baja frecuencia de aparición, representando el 22,7 por ciento de las anomalías estudiadas. Este trabajo permitió realizar un diagnóstico preciso de las anomalías cromosomales, principalmente a través de una técnica de bajo costo, fácil ejecución y buena confiabilidad, técnicas que están disponibles para el examen citogenético para la comunidad y así contribuir de manera significativa en la calidad de vida de los pacientes.