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RASopathies encompass a diverse set of disorders affecting genes that encode proteins within the RAS-MAPK pathway. RASA1 mutations are the cause of an autosomal dominant disorder called capillary malformation-arteriovenous malformation type 1 (CM-AVM1). Unlike other RASopathies, facial dysmorphism has not been described in these patients. We phenotypically delineated a large family of individuals with multifocal fast-flow capillary malformations, severe lymphatic anomalies of perinatal onset, and dysmorphic features not previously described. Sequencing studies were performed on probands and related family members, confirming the segregation of dysmorphic features in affected members of a novel heterozygous variant in RASA1 (NM_002890.3:c.2366G>A, p.(Arg789Gln)). In this work, we broaden the phenotypic spectrum of CM-AVM type 1 and propose a new RASA1 variant as likely pathogenic.
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Mutação em Linhagem Germinativa , Linhagem , Fenótipo , Proteína p120 Ativadora de GTPase , Humanos , Proteína p120 Ativadora de GTPase/genética , Masculino , Feminino , Mutação em Linhagem Germinativa/genética , Mancha Vinho do Porto/genética , Mancha Vinho do Porto/patologia , Criança , Adulto , Capilares/anormalidades , Capilares/patologia , Pré-Escolar , Lactente , Adolescente , Predisposição Genética para Doença , Fácies , Malformações ArteriovenosasRESUMO
Rare diseases affect millions of people worldwide, and most have a genetic etiology. The incorporation of next-generation sequencing into clinical settings, particularly exome and genome sequencing, has resulted in an unprecedented improvement in diagnosis and discovery in the past decade. Nevertheless, these tools are unavailable in many countries, increasing health care gaps between high- and low-and-middle-income countries and prolonging the "diagnostic odyssey" for patients. To advance genomic diagnoses in a setting of limited genomic resources, we developed DECIPHERD, an undiagnosed diseases program in Chile. DECIPHERD was implemented in two phases: training and local development. The training phase relied on international collaboration with Baylor College of Medicine, and the local development was structured as a hybrid model, where clinical and bioinformatics analysis were performed in-house and sequencing outsourced abroad, due to lack of high-throughput equipment in Chile. We describe the implementation process and findings of the first 103 patients. They had heterogeneous phenotypes, including congenital anomalies, intellectual disabilities and/or immune system dysfunction. Patients underwent clinical exome or research exome sequencing, as solo cases or with parents using a trio design. We identified pathogenic, likely pathogenic or variants of unknown significance in genes related to the patients´ phenotypes in 47 (45.6%) of them. Half were de novo informative variants, and half of the identified variants have not been previously reported in public databases. DECIPHERD ended the diagnostic odyssey for many participants. This hybrid strategy may be useful for settings of similarly limited genomic resources and lead to discoveries in understudied populations.
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Marfan Syndrome (MFS) is an autosomal dominant condition caused by variants in the fibrillin-1 (FBN1) gene. Cardinal features of MFS include ectopia lentis (EL), musculoskeletal features and aortic root aneurysm and dissection. Although dissection of the ascending aorta is the main cause of mortality in MFS, the clinical course differs considerably in age of onset and severity, even among individuals who share the same causative variant, suggesting the existence of additional genetic variants that modify the severity of the cardiovascular phenotype in MFS. We recruited MFS patients and classified them into severe (n = 8) or mild aortic phenotype (n = 14) according to age of presentation of the first aorta-related incident. We used Exome Sequencing to identify the genetic variants associated with the severity of aortic manifestations and we performed linkage analysis where suitable. We found five genes associated with severe aortic phenotype and three genes that could be protective for this phenotype in MFS. These genes regulate components of the extracellular matrix, TGFß pathway and other signaling pathways that are involved in the maintenance of the ECM or angiogenesis. Further studies will be required to understand the functional effect of these variants and explore novel, personalized risk management and, potentially, therapies for these patients.
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Síndrome de Marfan , Exoma/genética , Fibrilina-1/genética , Humanos , Síndrome de Marfan/genética , Mutação , FenótipoRESUMO
In the framework of the vaccination campaign against the SARS-CoV-2 virus, the Chilean Ministry of Health requested advice from the Genetics Branch of the Chilean Society of Pediatrics, to define the level of prioritization for people with Down Syndrome . A panel of geneticists worked on the development of this consensus, in which not only patients with Down syndrome were included, but the search was extended to patients with other types of disabilities, in both pediatric and adult ages in or der to contribute to the development of public health measures against the COVID-19 pandemic. The consensus concludes that, given the prevalence of comorbidities associated with Down syndrome, the higher incidence of cases with severe COVID-19 in this population group and a higher mortality, individuals with trisomy 21 should be considered as a high-risk population, and therefore, vaccina tion against SARS-CoV-2 should have a high priority for all people with Down syndrome regardless of their age (except for the age limit established by the clinical trials of each vaccine), and should be preceded only by the groups of health personnel and adults aged > 60-65 years. Likewise, this group of experts urges health authorities to include people with intellectual disabilities and related conditions as a priority population (other chromosomal abnormalities other than Down syndrome, intellectual disability, congenital anomalies and conditions that cause disability with microcephaly), as well as the caregivers of people with this type of conditions. Vaccination in children with this type of disorders should be considered as part of the first priority group, once safe vaccines against SARS-CoV-2 are available for use in children and adolescents.
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Vacinas contra COVID-19 , COVID-19/prevenção & controle , Síndrome de Down/complicações , Alocação de Recursos para a Atenção à Saúde/normas , Doenças Raras/complicações , Adolescente , Adulto , Idoso , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/etiologia , Criança , Chile/epidemiologia , Alocação de Recursos para a Atenção à Saúde/métodos , Humanos , Incidência , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
Skeletal dysplasias (SD) are disturbances in growth due to defects intrinsic to the bone and/or cartilage, usually affecting multiple bones and having a progressive character. In this article, we review the state of clinical and research SD resources available in Latin America, including three specific countries (Brazil, Argentina, and Chile), that have established multidisciplinary clinics for the care of these patients. From the epidemiological point of view, the SD prevalence of 3.2 per 10,000 births from nine South American countries included in the ECLAMC network represents the most accurate estimate not just in Latin America, but worldwide. In Brazil, there are currently five groups focused on SD. The data from one of these groups including the website www.ocd.med.br, created to assist in the diagnosis of SD, are highlighted showing that telemedicine for this purpose represents a good strategy for the region. The experience of more than 30 years of the SD multidisciplinary clinic in an Argentinian Hospital is presented, evidencing a solid experience mainly in the follow-up of the most frequent SD, especially those belonging the FGFR3 group and OI. In Chile, a group with 20 years of experience presents its work with geneticists and pediatricians, focusing on diagnostic purposes and clinical management. Altogether, although SD health-care and research activities in Latin America are in their early stages, the experience in these three countries seems promising and stimulating for the region as a whole.
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Osteocondrodisplasias , Argentina , Osso e Ossos , Humanos , América Latina/epidemiologia , PrevalênciaRESUMO
INTRODUCCIÓN: El diagnóstico prenatal de anomalías congénitas tiene como objetivo ofrecer consejería apropiada, identificar aquellas patologías que se benefician de terapia fetal y coordinar la derivación de estas pacientes a centros terciarios para un óptimo manejo perinatal. Para el diagnóstico y manejo de las anomalías congénitas en el Hospital Dr. Sótero Del Río contamos con un equipo multidisciplinario. El objetivo de este estudio es describir nuestra experiencia como centro de referencia en Santiago de Chile en relación al diagnostico prenatal de malformaciones congénitas, estudio genético prenatal y resultados perinatales. MÉTODOS: Estudio retrospectivo y descriptivo. Se incluyó a las pacientes registradas en las bases de datos ecográficas entre 2010 y 2019 del Hospital Dr. Sotero del Rio. Se revisaron fichas clínicas para evaluación y seguimiento postnatal. RESULTADOS: Se evaluaron 404 pacientes con sospecha de malformaciones congénitas o marcadores de aneuploidías. La edad gestacional media de la evaluación fue 29 semanas (14-38 semanas). La mediana de la edad gestacional al parto fue 37.6 semanas (20-41 semanas). Se obtuvo un 78% de recién nacidos vivos, 12% óbitos fetales y 10% mortineonatos. Las malformaciones más frecuentes fueron cardiovasculares, sistema nervioso central, hidrops, extremidades, abdomen y genitourinario. Se realizo el estudio genético en 232 pacientes; 61% resultado normal, 12.5% trisomía 21, 8% trisomía 18, 4% trisomía 13, 4% XO, 4% otras. Se analizaron las pacientes que se acogieron a la ley de interrupción voluntaria del embarazo. CONCLUSIÓN: Destacamos la importancia de derivación a centros de referencia de pacientes con sospecha de malformaciones congénitas para un adecuado diagnostico prenatal, ofrecer un manejo con equipo multidisciplinario y así mejorar los resultados neonatales.
INTRODUCTION: The objectives of prenatal diagnosis of fetal malformations are to offer the patient and her family the proper counseling, identify those conditions that benefits of prenatal therapy and to coordinate the referral to tertiary centers to improve neonatal survival. Our hospital counts with a multidisciplinary team who evaluate the patients together. The objective of this study is to describe our experience as a referral center in prenatal diagnosis, management and neonatal outcomes in Santiago de Chile. METHODS: Retrospective and descriptive study. Patients registered in our prenatal diagnosis database between September 2010 and July 2019 were included. Clinical files were reviewed for neonatal outcomes. OUTCOMES: 404 patients with congenital malformations or aneuploidy markers were evaluated. The average gestational age of the evaluation was 29 weeks. Median gestational age to delivery was 37 weeks plus 6 days. 78% of livebirth, 12% fetal demise and 10% of neonatal death were obtained. The most frequent fetal malformations were cardiovascular, central nervous system, fetal hydrops, extremities, abdominal wall defects and urinary system. Fetal karyotype was performed in 232 patients; 61% normal karyotype, 12.5% trisomy 21, 8% trisomy 18, 4% trisomy 13, 4% monosomy X, 4% others. We also analyze the patients who agreed to termination of pregnancy according to Chilean legislation. CONCLUSION: We highlight the importance of referral of patients with suspected fetal malformations to tertiary centers for an adequate evaluation by a multidisciplinary team of specialists, to improve the survival and neonatal outcome.
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Humanos , Feminino , Gravidez , Adolescente , Adulto , Pessoa de Meia-Idade , Diagnóstico Pré-Natal/estatística & dados numéricos , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/epidemiologia , Equipe de Assistência ao Paciente , Encaminhamento e Consulta , Anormalidades Congênitas/genética , Resultado da Gravidez , Epidemiologia Descritiva , Estudos Retrospectivos , Seguimentos , Idade GestacionalRESUMO
22q11.2 microdeletion syndrome (22q11.2DS) is the most common microdeletion disorder in humans, with an incidence of 1/4000 live births. It is caused by a heterozygous deletion of 1.5-3 Mb on chromosome region 22q11.2. Patients with the deletion present features that include neuropsychiatric problems, craniofacial abnormalities and cardiovascular malformations. However, the phenotype is highly variable and the factors related to the clinical heterogeneity are not fully understood. About 65% of patients with 22q11.2DS have congenital heart defects (CHD). The main goal of this study was to identify common CNVs in 22q11.2DS patients that could be associated with the incomplete penetrance of CHD. Analysis of genomic DNA from 253 patients with 22q11.2DS using array technology showed an association between a microduplication located in region 17q21.31 and CHD (p-value = 0.023, OR = 2.75, 95% CI = 1.17-7.03). This region includes the first three exons of KANSL1 gene. Bioinformatic analysis showed that KANSL1 and CRKL, a gene in the commonly deleted region of 22q11.2DS, are part of the same regulatory module in a miRNA-mRNA network. These results show that a KANSL1 microduplication, in combination with the 22q11.2 deletion, is associated with increased risk of CHD in these patients, suggesting that KANSL1 plays a role as a modifier gene in 22q11.2DS patients.
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Duplicação Cromossômica , Síndrome de DiGeorge/genética , Cardiopatias Congênitas/genética , Proteínas Nucleares/genética , Variações do Número de Cópias de DNA , Síndrome de DiGeorge/diagnóstico , Epistasia Genética , Frequência do Gene , Estudo de Associação Genômica Ampla , Cardiopatias Congênitas/diagnóstico , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Proximal deletion of 6q is a relatively rare chromosomal abnormality. Reported patients have deletions of different sizes but share partial overlap and present with similar clinical features, and some of them were described prior to the introduction of chromosome microarrays. We describe a male patient with prenatal sonographic findings of nuchal edema, intrauterine growth restriction, renal pelvis dilatation, and oligohydramnios. At birth, facial dysmorphism, retro/micrognathia, a short and wide neck as well as cardiovascular and renal anomalies were noted. His clinical evolution has been marked by failure to thrive, severe developmental delay, and cognitive impairment. The diagnosis of Toriello-Carey syndrome (TCS) was based on his "gestalt." aCGH identified a de novo proximal deletion of 17 Mb in 6q (6q12q14.3). Deletion 6q13q14 seems to be responsible for the main facial features and should be considered within the differential diagnosis of TCS.
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OBJECTIVES: Clinical use of microarray-based techniques for the analysis of many developmental disorders has emerged during the last decade. Thus, chromosomal microarray has been positioned as a first-tier test. This study reports the first experience in a Chilean cohort. METHODS: Chilean patients with developmental disabilities and congenital anomalies were studied with a high-density microarray (CytoScan(tm) HD Array, Affymetrix, Inc., Santa Clara, CA, USA). Patients had previous cytogenetic studies with either a normal result or a poorly characterized anomaly. RESULTS: This study tested 40 patients selected by two or more criteria, including: major congenital anomalies, facial dysmorphism, developmental delay, and intellectual disability. Copy number variants (CNVs) were found in 72.5% of patients, while a pathogenic CNV was found in 25% of patients and a CNV of uncertain clinical significance was found in 2.5% of patients. CONCLUSION: Chromosomal microarray analysis is a useful and powerful tool for diagnosis of developmental diseases, by allowing accurate diagnosis, improving the diagnosis rate, and discovering new etiologies. The higher cost is a limitation for widespread use in this setting. .
OBJETIVO: O uso clínico de técnicas baseadas em microarrays para a análise de transtornos de desenvolvimento tem surgido durante a última década. Assim, o microarray cromossômico tem sido posicionado como um teste de primeiro nível clínico. Relatamos a primeira experiência em uma coorte chilena. MÉTODOS: Pacientes chilenos com atraso de desenvolvimento e anomalias congênitas foram estudados com um microarray de alta densidade (CytoScan(tm) HD Array, Affymetrix, Inc., Santa Clara, CA, EUA). Pacientes tiveram estudos citogenéticos anteriores, ou um resultado normal ou de uma anomalia não bem caracterizada. RESULTADOS: Foram analisados 40 pacientes selecionados por dois ou mais critérios, incluindo: anomalias congênitas maiores, dismorfismo facial, atraso de desenvolvimento e deficiência intelectual. Uma variante do número de cópia (CNV) foi encontrada em 72,5% dos pacientes, enquanto que uma CNV patogênica foi encontrada em 25% dos pacientes e uma CNV de significado clínico incerto foi encontrada em 2,5% dos pacientes. CONCLUSÕES: A análise cromossômica microarray é uma ferramenta útil e poderosa em transtornos de desenvolvimento, permite um diagnóstico preciso, melhora a taxa de diagnóstico e descobre novas etiologias. O custo mais elevado é uma limitação para um uso difundido em nossa realidade. .
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Idoso , Feminino , Humanos , Masculino , Envelhecimento/psicologia , Amnésia/complicações , Aprendizagem , Memória , Disfunção Cognitiva/psicologia , Rememoração Mental , Disfunção Cognitiva/complicaçõesRESUMO
OBJECTIVES: Clinical use of microarray-based techniques for the analysis of many developmental disorders has emerged during the last decade. Thus, chromosomal microarray has been positioned as a first-tier test. This study reports the first experience in a Chilean cohort. METHODS: Chilean patients with developmental disabilities and congenital anomalies were studied with a high-density microarray (CytoScan™ HD Array, Affymetrix, Inc., Santa Clara, CA, USA). Patients had previous cytogenetic studies with either a normal result or a poorly characterized anomaly. RESULTS: This study tested 40 patients selected by two or more criteria, including: major congenital anomalies, facial dysmorphism, developmental delay, and intellectual disability. Copy number variants (CNVs) were found in 72.5% of patients, while a pathogenic CNV was found in 25% of patients and a CNV of uncertain clinical significance was found in 2.5% of patients. CONCLUSION: Chromosomal microarray analysis is a useful and powerful tool for diagnosis of developmental diseases, by allowing accurate diagnosis, improving the diagnosis rate, and discovering new etiologies. The higher cost is a limitation for widespread use in this setting.
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Anormalidades Múltiplas/genética , Aberrações Cromossômicas , Hibridização Genômica Comparativa/métodos , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Anormalidades Múltiplas/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Chile , Estudos de Coortes , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Lactente , Masculino , Adulto JovemRESUMO
OBJECTIVE: Chromosome 22q11.2 deletion is the most commonly occurring known microdeletion syndrome. Deaths related to the syndrome have been reported, but the magnitude of death has not been quantified. This study evaluated the deletion's impact on survival and its clinical manifestations in a large cohort of Chilean patients. DESIGN: Demographic and clinical data of individuals with 22q11 deletions diagnosed between 1998 and 2013 were collected from medical records and death certificates. Case fatality rate was calculated and compared with national vital statistics. OR with 95% CI analysis was used to assess the association between clinical manifestations and death. SETTING: Genetic services in tertiary care centres in Chile, following patients with 22q11.2 deletion. OUTCOMES: Fatality rate and associated factors. RESULTS: 59 of 419 patients (14.1%) died during the study period at a median of 3.4 months (range 0 to 32 years of age). Factors associated with death included congenital heart disease (OR 5.27; 95% CI 2.06 to 13.99; p<0.0001), hypocalcaemia (OR 4.27; 95% CI 1.67 to 11.15; p<0.002) and airway malacia (OR 13.37; 95% CI 1.19 to 110.51; p<0.002). Patients with deletions and defects such as tetralogy of Fallot with or without pulmonary atraesia, truncus arteriosus or ventricular septal defect, had a 2.6-fold to 4.6-fold higher death rate compared with nationwide reports for the same types of defects. CONCLUSIONS: In this cohort, we observed a death rate of 14.1%, implying that one in seven patients with 22q11 deletion died during the study period. Significant associations with cardiac defects, hypocalcaemia and airway malacia were observed. Furthermore, the death risk in patients with 22q11 deletion and cardiac defects exceeded the global figures observed in Chile for infants with structurally similar but apparently isolated anomalies. These observations indicate a need to identify patients who may require specific perioperative management to improve survival.
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Síndrome da Deleção 22q11/mortalidade , Adolescente , Adulto , Criança , Pré-Escolar , Chile , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
In the South American Republic of Chile genetic counseling is not currently recognized as an independent clinical discipline, and in general is provided by physicians with training in clinical genetics. At present only one genetic counselor and 28 clinical geneticists practice in this country of over 16 million inhabitants. Pediatric dysmorphology constitutes the primary area of practice in clinical genetics. Although the country has a universal health care system and an adequate level of health care, genetic conditions are not considered a health care priority and there is a lack of clinical and laboratory resources designated for clinical genetics services. Multiple educational, cultural and financial barriers exist to the growth and development of genetic counseling services in Chile. However, during the last 10 years increased awareness of the importance of identifying individuals at risk for inherited cancer syndromes led to growing interest in the practice of cancer genetics.
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Aconselhamento Genético , Genética Médica , Chile , Atenção à Saúde/organização & administração , HumanosRESUMO
OBJECTIVE: Chromosome 22q11 microdeletion syndrome (del22q11) is the most frequent microdeletion syndrome in humans, with an estimated incidence of 1/4000. It is recognized as a common identifiable cause of cleft palate. We characterized palatal abnormalities in a large cohort of Chilean patients with del22q11. METHODS: Patients with the deletion were evaluated by geneticists and speech pathologists, including nasopharyngoscopy when indicated. Comparisons between groups with and without palatal abnormalities were performed using Fisher's exact test and Mann-Whitney U test. RESULTS: Two hundred and one patients were included in the study. Palate abnormalities were present in 154 patients (76.6%). The most frequent finding was submucous cleft palate (both classic and occult forms) seen in 80 patients (39.8% of the total group). Overt cleft palate or cleft lip/palate was seen in 30 patients (14.9%). Patients without palate abnormalities had significantly greater frequency of congenital heart disease and higher mortality. CONCLUSIONS: Our data show a high frequency of palate abnormalities without significant association with congenital heart disease. The most common types of palate defects seen in this series are usually not evident on physical examination and thus require a high index of suspicion and active evaluation through nasopharyngoscopy.
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Deleção Cromossômica , Cromossomos Humanos Par 22 , Fissura Palatina/epidemiologia , Fissura Palatina/genética , Predisposição Genética para Doença/epidemiologia , Insuficiência Velofaríngea/genética , Adolescente , Adulto , Distribuição por Idade , Estudos de Casos e Controles , Criança , Pré-Escolar , Chile/epidemiologia , Fenda Labial/epidemiologia , Fenda Labial/genética , Fenda Labial/fisiopatologia , Fissura Palatina/fisiopatologia , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Distribuição por Sexo , Estatísticas não Paramétricas , Síndrome , Insuficiência Velofaríngea/epidemiologia , Insuficiência Velofaríngea/fisiopatologia , Adulto JovemRESUMO
Chromosome 22q11 microdeletion syndrome has a wide range of clinical manifestations including congenital heart malformations, palatal defects, endocrine abnormalities, immunologic deficits, learning difficulties, and an increased predisposition to psychiatric disease. Short stature and poor weight gain in infancy are common findings and are usually seen in the absence of hormone deficiencies. An increased frequency of obesity has been observed in adolescents and adults. We generated gender-specific growth curves from 0 to 24 months of age, based on 479 length and 475 weight measurements from 138 Chilean patients with 22q11 deletion. Final adult height and weight on 25 individuals were analyzed. The 10th, 50th, and 90th centile-smoothed curves for infants were built using the LMS method and compared with World Health Organization Child Growth Standards. The 50th centile for length in the deleted patients was slightly lower than the 10th centile of WHO standards in boys and girls. The same was observed for weight, although a trend toward a gradual increase near 2 years of age was observed, particularly in boys. Average adult height was 152 cm (ranging from 143 to 162 cm) in females, corresponding to the 10th centiles of WHO standards, and 166 cm for males (160-172 cm), at the 20th centile of WHO standards. A third of the adult females and none of the males had body mass index (BMI) greater than 25. The curves should be useful to monitor growth in infants with 22q11 microdeletion syndrome.
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Síndrome da Deleção 22q11/diagnóstico , Gráficos de Crescimento , Pesos e Medidas Corporais , Pré-Escolar , Chile , Feminino , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
BACKGROUND: CFTR gene mutations have worldwide differences in prevalence and data on Chilean patients is scarce. METHODS: We studied 36 of the most common CFTR mutations in Chilean patients from the CF National Program [Programa Nacional de Fibrosis Quística (PNFQ)] of the Ministry of Health of Chile. RESULTS: Two hundred and eighty-nine patients were studied. Fourteen different mutations were identified with an overall allele detection rate of 42.0%. Mutations with frequencies greater than 1% were p.F508del (30.3% of alleles), p.R334W (3.3%), p.G542X (2.4%), c.3849+10Kb C>T (1.7%), and p.R553X (1.2%). A north to south geographical gradient was observed in the overall rate of detection. CONCLUSIONS: Southern European CFTR mutations predominate in the Chilean population, but a high percentage of alleles remain unknown. Geographical heterogeneity could be explained in part by admixture. Complementary analyses are necessary to allow for effective genetic counselling and improve cost-effectiveness of screening and diagnostic tests.
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Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística , Alelos , Chile/epidemiologia , Fibrose Cística/epidemiologia , Fibrose Cística/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Mutação , PrevalênciaRESUMO
BACKGROUND: Microtia is a congenital defect characterized by disturbances in the size and form of the ear lobe. Anotia corresponds to the absence of the ear lobe. AIM: To study the prevalence of microtia and anotia at the Maternity of the University of Chile Clinical Hospital. MATERIAL AND METHODS: Analysis of the database of the Latin American Collaborative Study of Congenital Defects (ECLAMC). All newborns and stillborns with congenital defects are incorporated to this database. RESULTS: The prevalence of microtia-anotia in the period 1982-2001 was 8.7 per 10,000 born alive. Chilean hospitals have an uniform prevalence of 5.2 per 10,000 born alive. Thirty seven percent presented as isolated malformations and the rest were associated to other defects. Eighty six percent of non isolated cases were part of a syndrome. Sixty eight percent were mild or moderate forms and the rest, severe forms. Two cases were stillborns and two newborns died before hospital discharge. CONCLUSIONS: The prevalence of microtia in this hospital and in the rest of Chilean hospitals is significantly higher than in the rest of non Chilean hospitals participating in the ECLAMC, that is 4.1 per 10,000 born alive.
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Orelha Externa/anormalidades , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Chile/epidemiologia , Anormalidades Congênitas/epidemiologia , Feminino , Maternidades , Hospitais Universitários , Humanos , Recém-Nascido , Nascido Vivo , Masculino , Prevalência , Índice de Gravidade de Doença , NatimortoAssuntos
Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/estatística & dados numéricos , Defeitos do Tubo Neural/prevenção & controle , Adulto , Chile , Feminino , Doenças Fetais/prevenção & controle , Educação em Saúde/normas , Pessoal de Saúde/normas , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Inquéritos e QuestionáriosRESUMO
A sample of 64 high-risk breast and/or ovarian cancer families from Chile were screened for germline mutations in the coding sequences and exon-intron boundaries of BRCA1 (MIN no. 113705) and BRCA2 (MIN no. 600185) genes using conformation-sensitive gel electrophoresis, and the mutations found were confirmed with direct sequencing. Seven families (10.9%) were found to carry BRCA1 mutations and three families (4.7%) had BRCA2 mutations. Six different pathogenic mutations were detected in BRCA1, four that had been reported previously (c.187_188delAG; c.300T-->G, c.3450_3453delCAAG and IVS17-1G-->A) and two novel mutations (c.2605_2606delTT and c.4185_4188delCAAG). In BRCA2, we found three different pathogenic mutations, two previously described (c.6174delT and c.6503_6504delTT) and one novel mutation (c.5667delT). We also identified nine variants of unknown significance (five in BRCA1 and four in BRCA2). These findings indicate that the Chilean population has a heterogeneous spectrum of prevalent BRCA mutations. Given the results obtained in our study, the screening of the entire BRCA1 and BRCA2 coding regions is necessary for the molecular genetic testing of Chilean high-risk breast/ovarian cancer patients. To our knowledge, this is the first genetic study of BRCA gene mutations conducted in Chile. The Chilean population has a well-known admixed Amerindian-Caucasian ratio and, therefore, our findings are not only important per se, but they constitute the basis for improved and more specific genetic counselling, as well as to support for preventive campaigns geared toward the Chilean population.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , DNA de Neoplasias/genética , Mutação em Linhagem Germinativa , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Chile/epidemiologia , Feminino , Testes Genéticos , Genética Populacional , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologiaRESUMO
BRCA1 gene mutations account for nearly all families with multiple cases of both early onset breast and/or ovarian cancer and about 30% of hereditary breast cancer. Although to date more than 1,237 distinct mutations, polymorphisms, and variants have been described, several mutations have been found to be recurrent in this gene. We have analyzed 63 Chilean breast/ovarian cancer families for eighteen frequent BRCA1 mutations. The analysis of the five exons and two introns in which these mutations are located was made using mismatch PCR assay, ASO hybridization assay, restriction fragment analysis, allele specific PCR assay and direct sequentiation techniques. Two BRCA1 mutations (185delAG and C61G) and one variant of unknown significance (E1250K) were found in four of these families. Also, a new mutation (4185delCAAG) and one previously described polymorphism (E1038G) were found in two other families. The 185delAG was found in a 3.17 % of the families and the others were present only in one of the families of this cohort. Therefore these mutations are not prominent in the Chilean population. The variant of unknown significance and the polymorphism detected could represent a founder effect of Spanish origin.