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1.
Genes (Basel) ; 14(8)2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37628591

RESUMO

Danon disease is a rare x-linked dominant multisystemic disorder with a clinical triad of severe cardiomyopathy, skeletal myopathy, and intellectual disability. It is caused by defects in the lysosome-associated membrane protein-2 (LAMP2) gene. Numerous different mutations in the LAMP2 protein have been described. Danon disease is typically lethal by the mid-twenties in male patients due to cardiomyopathy and heart failure. Female patients usually present with milder and variable symptoms. This report describes a 42-year-old father and his 3-year-old daughter presenting with mild manifestations of the disease. The father has normal intellectual development and normal physical activity. At the age of 13, he was diagnosed with mild ventricular pre-excitation known as Wolf-Parkinson-White syndrome (WPWs), very mild and mostly asymptomatic cardiomyopathy and left ventricular hypertrophy, and at about the age of 25 presented with visual impairment due to cone-rod dystrophy. His daughter showed normal development and very mild asymptomatic electrocardiographic WPWs abnormalities with left mild ventricular hypertrophy. Genetic testing revealed an Xq24 microdeletion encompassing the entire LAMP2 gene. Relevant literature was reviewed as a reference for the etiology, diagnosis, treatment and case management.


Assuntos
Distrofias de Cones e Bastonetes , Doença de Depósito de Glicogênio Tipo IIb , Insuficiência Cardíaca , Feminino , Masculino , Humanos , Doença de Depósito de Glicogênio Tipo IIb/diagnóstico , Doença de Depósito de Glicogênio Tipo IIb/genética , Deleção de Genes , Genes Reguladores , Proteína 2 de Membrana Associada ao Lisossomo/genética
2.
Harefuah ; 162(6): 352-358, 2023 Jun.
Artigo em Hebraico | MEDLINE | ID: mdl-37394436

RESUMO

BACKGROUND: Short stature is a common finding among the general population, mostly presented as an isolated phenotype. The syndromic short statute is rare and complex. Recently, we examined several patients from related families sharing both short stature and congenital dental abnormalities. OBJECTIVES: 1. Clinical characterization of syndromic short stature; 2. To find the disease mutation and evaluate the carrier state in the particular community. METHODS: Clinical characterization- by medical history, medical records and physical examination; Homozygosity mapping - by using the Single nucleotide polymorphism (SNP) chromosomal microarrays (CMA) analysis and gene mutation detection by ABI Sanger sequence. RESULTS: All patients present with short stature severe dental anomalies including enamel formation and mineralization defect, oligodontia, abnormal shape and retarded eruption. CMA analysis in 3 patients and 2 healthy members of four families was normal. One homozygote region in chromosome 11 (11p11.2- 11q13.3) was found in all patients. By using the candidate gene approach, amongst the 301 genes found within this region, only one, the LTBP3 gene (Latent Transforming Growth Factor-Beta-Binding Protein-3) has high priority for sequence. Hence, LTBP3 (OMIM-602090) pathogenic variant is responsible for "brachyolmia with amelogenesis imperfecta" also known as "Dental Anomalies and Short Stature (DASS)" (OMIM- 601216). We sequenced all 29 LTBP3 exons and a novel splice pathogenic variant, c.1346-1G>A chr11:65319629, in exon 8 was identified. The variant segregated well within healthy tested family members. We found a high carrier rate in the village (1:15). CONCLUSIONS: We identified a novel and common LTBP3 gene pathogenic variant responsible for short stature, brachyolmia and amelogenesis imperfecta in Druze Arab patients.


Assuntos
Amelogênese Imperfeita , Osteocondrodisplasias , Humanos , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Árabes , Mutação , Osteocondrodisplasias/genética , Proteínas de Ligação a TGF-beta Latente/genética
3.
Urol Oncol ; 41(6): 296.e1-296.e8, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36642638

RESUMO

OBJECTIVE: To compare the performance of CellDetect, a new biomarker with urine cytology and UroVysiontechnology for bladder cancer detection. PATIENTS AND METHODS: We performed an IRB approved prospective, blinded single center study in patients on routine surveillance for nonmuscle invasive bladder cancer and those scheduled for transurethral resection of bladder tumor or radical cystectomy. Patients with bladder catheters, neobladder, ileal conduit, urinary stones, or those with upper tract carcinoma were excluded from the study. Voided urine sample was collected from the participants and each sample was divided into three equal aliquots (CellDetect, Urine cytology and Urovysion). Pathology of the operative specimen was considered the gold standard to which the three markers were compared. RESULTS: The study group included 93 patients with median age was 68 years (range: 34-92 years) with male to female ratio of 12:1. Pathologic evaluation revealed malignancy in 43 cases (46%) of whom 81% had previous history of urothelial bladder cancer. Among all studied markers CellDetect exhibited the best performance followed by urine cytology and U-FISH with diagnostic odds ratio of 4.33, 3.85, and 2.5 respectively. The overall sensitivity, specificity, negative predictive value, and positive predictive value for this test were 84%, 80%, 88%, and 74% respectively. The advantage of this new biomarker was observed both in high grade and low-grade cases. CONCLUSIONS: This study demonstrates the advantage of CellDetect as a urine-based assay to detect urothelial bladder cancer over urine cytology and U-FISH test. The high performance was maintained across all cancer grades and stages without compromising the assay specificity. Additional studies are required to test if it can be a noninvasive alternative to cystoscopy.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Masculino , Feminino , Humanos , Citologia , Estudos Prospectivos , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/patologia , Urina
4.
Comput Biol Med ; 145: 105490, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35405402

RESUMO

BACKGROUND: Chronic lymphocytic leukemia (CLL) is one of the most common types of leukemia in the western world which affects mainly the elderly population. Progress of the disease is very heterogeneous both in terms of necessity of treatment and life expectancy. The current scoring system for prognostic evaluation of patients with CLL is called CLL-IPI and predicts the general progress of the disease but is not a measure or a decision aid for the necessity of treatment. Due to the heterogeneous behavior of CLL it is important to develop tools that will identify if and when patients will necessitate treatment for CLL. Recently, Machine Learning (ML) has spread to many public health fields including diagnosis and prognosis of diseases. OBJECTIVE: Existing machine learning methods for CLL treatment prediction rely on expensive tests, such as genetic tests, rendering them useless in peripheral or low-resource clinics such as those in developing countries. We aim to develop a model for predicting whether a patient will need treatment for CLL within two years of diagnosis using a machine learning model based on only on demographic data and routine laboratory tests. METHOD: We conducted a single center study that included adult patients (above the age of 18) that were diagnosed with CLL according to the IWCLL criteria and were under observation at the hematology unit of the Bnai-Zion medical center between 2009 and 2019. Patient data include demographic, clinical and laboratory measures that were extracted from patients' medical records anonymously. All laboratory results, during the observation period, were extracted for the entire cohort. Multiple ML approaches for classifying whether a patient will require treatment during a predetermined period of 2 years were evaluated. Performance of the ML models was measured using repeated cross validation. We evaluated the use of SHapley Additive exPlanation (SHAP) for explaining what influences the models decision. Additionally, we employ a method for extracting a single decision tree from the ML model which enables the doctor to understand the main logic governing the model prediction. RESULTS: The study included 109 patients of them 67 males (61%). Patients were under observation for a median of 44 months and the median age was 65 (age range: 45-87). 64% of the cohort received therapy during follow-up. A Gradient Boosting Model (GBM) model using all of the extracted variables to identify the need for treatment in the coming two years among patients with CLL achieved the AUPRC of 0.78 (±0.08). An identical GBM model, without genetic/FISH and flowcytometry (FACS) data, such that it can be used in peripheral clinics, scored an AUPRC of 0.7686 (±0.0837). A Generalized Linear Model (GLM) using the same features, scored an AUPRC of 0.7535 (±0.0995). All the models described above surpassed the performance of CLL-IPI that was evaluated using the CLL-TIM model. According to the SHAP results, red blood cell (RBC) count was the most predictive value for the necessity for treatment, where a high value is associated with a low probability of requiring treatment in the coming two years. Additionally, the SHAP method was used for estimating the personal risk of a random patient and showed sensible results. A simple Decision Tree classifier showed that patients who had a hemoglobin level of less than 13 gm/dL and a Neutrophil to Lymphocyte Ratio (NLR) less than 0.063, which constituted 34% percent of the patients included in our study, had a high probability (76%) of requiring treatment. CONCLUSIONS: Machine Learning algorithms that were evaluated in this work for predicting the necessity of treatment for patients with CLL achieved reasonable accuracy which surpassed that of CLL-IPI which was evaluated using the CLL-TIM model. Furthermore, we found that a machine learning model trained exclusively using inexpensive features only incurred a modest decrease in performance compared to the model trained using all of the features. Due to the small number of patients in this study it is necessary to validate the results on a larger population.


Assuntos
Leucemia Linfocítica Crônica de Células B , Idoso , Algoritmos , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Aprendizado de Máquina , Masculino
5.
Eur J Med Genet ; 63(2): 103643, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30922925

RESUMO

Majewski Osteodysplastic Primordial Dwarfism type II (MOPDII) is a form of dwarfism associated with severe microcephaly, characteristic skeletal findings, distinct dysmorphic features and increased risk for cerebral infarctions. The condition is caused by bi-allelic loss-of-function variants in the gene PCNT. Here we describe the identification of a novel founder pathogenic variant c.3465-1G > A observed in carriers from multiple Druze villages in Northern Israel. RNA studies show that the variant results in activation of a cryptic splice site causing a coding frameshift. The study was triggered by the diagnosis of a single child with MOPDII and emphasizes the advantages of applying next generation sequencing technologies in community genetics and the importance of establishing population-specific sequencing databases.


Assuntos
Antígenos/genética , Efeito Fundador , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação , Adolescente , Alelos , Linhagem Celular Tumoral , Análise Mutacional de DNA , Nanismo/diagnóstico , Nanismo/genética , Fácies , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/genética , Estudos de Associação Genética/métodos , Testes Genéticos , Humanos , Israel , Masculino , Microcefalia/diagnóstico , Microcefalia/genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Linhagem , Fenótipo , Sequenciamento do Exoma
6.
Sci Rep ; 9(1): 6104, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30967570

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

7.
Sci Rep ; 9(1): 3818, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846778

RESUMO

Surrounded by speakers of Indo-European, Dravidian and Tibeto-Burman languages, around 11 million Munda (a branch of Austroasiatic language family) speakers live in the densely populated and genetically diverse South Asia. Their genetic makeup holds components characteristic of South Asians as well as Southeast Asians. The admixture time between these components has been previously estimated on the basis of archaeology, linguistics and uniparental markers. Using genome-wide genotype data of 102 Munda speakers and contextual data from South and Southeast Asia, we retrieved admixture dates between 2000-3800 years ago for different populations of Munda. The best modern proxies for the source populations for the admixture with proportions 0.29/0.71 are Lao people from Laos and Dravidian speakers from Kerala in India. The South Asian population(s), with whom the incoming Southeast Asians intermixed, had a smaller proportion of West Eurasian genetic component than contemporary proxies. Somewhat surprisingly Malaysian Peninsular tribes rather than the geographically closer Austroasiatic languages speakers like Vietnamese and Cambodians show highest sharing of IBD segments with the Munda. In addition, we affirmed that the grouping of the Munda speakers into North and South Munda based on linguistics is in concordance with genome-wide data.


Assuntos
Variação Genética , Genética Populacional , Haplótipos , Idioma , Sudeste Asiático , DNA Mitocondrial/genética , Bases de Dados Genéticas , Etnicidade , Frequência do Gene , Humanos , Índia , Filogenia
8.
J Matern Fetal Neonatal Med ; 32(16): 2643-2648, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29455582

RESUMO

OBJECTIVE: The objective of this study is to examine the frequency of abnormal Chromosomal Microarray (CMA) analyses among fetuses with isolated non-visualization of fetal gallbladder. METHODS: Data from CMA analyses performed due to isolated non-visualization of fetal gallbladder between January 2013 and September 2016 were retrospectively acquired from a computerized database of the Israeli Ministry of Health. The results were compared with the rate for clinically significant CMA findings in general population, based on a large cohort of 5541 pregnancies undergoing CMA due to maternal request, and a systematic review of 9272 cases with normal ultrasound. RESULTS: Of 45 pregnancies with isolated non-visualization of fetal gallbladder, CMA testing yielded one (2.22%) gain-of-copy-number variant at 16p11.2, categorized as "pathogenic". In addition, one finding of unknown significance was demonstrated. The risk for clinically meaningful CMA findings among pregnancies with isolated absent gallbladder was not significantly increased compared to control population. CONCLUSIONS: To the best of our knowledge, this study is the first report describing the rate of pathogenic CMA results in fetuses with isolated non-visualization of fetal gallbladder. The results, in conjunction with previous studies, show that the risk for abnormal CMA results in pregnancies diagnosed with non-visualized gallbladder is not significantly different from pregnancies with normal ultrasound.


Assuntos
Anormalidades Congênitas/embriologia , Doenças Fetais/genética , Vesícula Biliar/anormalidades , Testes Genéticos/métodos , Adulto , Estudos de Casos e Controles , Anormalidades Congênitas/diagnóstico por imagem , Anormalidades Congênitas/genética , Feminino , Doenças Fetais/diagnóstico , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/embriologia , Testes Genéticos/estatística & dados numéricos , Humanos , Análise em Microsséries/estatística & dados numéricos , Gravidez , Estudos Retrospectivos
9.
J Med Genet ; 56(5): 340-346, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30327448

RESUMO

BACKGROUND: Dandy-Walker malformation features agenesis/hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle and enlargement of posterior fossa. Although Dandy-Walker malformation is relatively common and several genes were linked to the syndrome, the genetic cause in the majority of cases is unknown. OBJECTIVE: To identify the mutated gene responsible for Dandy-Walker malformation, kidney disease and bone marrow failure in four patients from two unrelated families. METHODS: Medical assessment, sonographic, MRI and pathological studies were used to define phenotype. Chromosomal microarray analysis and whole-exome sequence were performed to unravel the genotype. RESULTS: We report four subjects from two unrelated families with homozygous mutations in the Exocyst Complex Component 3-Like-2 gene (EXOC3L2).EXOC3L2 functions in trafficking of post-Golgi vesicles to the plasma membrane. In the first family a missense mutation in a highly conserved amino acid, p.Leu41Gln, was found in three fetuses; all had severe forms of Dandy-Walker malformation that was detectable by prenatal ultrasonography and confirmed by autopsy. In the second family, the affected child carried a nonsense mutation, p.Arg72*, and no detected protein. He had peritrigonal and cerebellar white matter abnormalities with enlargement of the ventricular trigones, developmental delay, pituitary hypoplasia, severe renal dysplasia and bone marrow failure. CONCLUSION: We propose that biallelic EXOC3L2 mutations lead to a novel syndrome that affects hindbrain development, kidney and possibly the bone marrow.


Assuntos
Alelos , Síndrome de Dandy-Walker/diagnóstico , Síndrome de Dandy-Walker/genética , Mutação , Fenótipo , Proteínas de Transporte Vesicular/genética , Biópsia , Encéfalo/patologia , Variações do Número de Cópias de DNA , Homozigoto , Humanos , Rim/metabolismo , Imageamento por Ressonância Magnética , Avaliação de Sintomas , Síndrome , Ultrassonografia , Proteínas de Transporte Vesicular/metabolismo , Sequenciamento do Exoma
10.
Hum Genet ; 137(2): 129-139, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29356938

RESUMO

The rugged topography of the Himalayan region has hindered large-scale human migrations, population admixture and assimilation. Such complexity in geographical structure might have facilitated the existence of several small isolated communities in this region. We have genotyped about 850,000 autosomal markers among 35 individuals belonging to the four major populations inhabiting the Himalaya and adjoining regions. In addition, we have genotyped 794 individuals belonging to 16 ethnic groups from the same region, for uniparental (mitochondrial and Y chromosomal DNA) markers. Our results in the light of various statistical analyses suggest a closer link of the Himalayan and adjoining populations to East Asia than their immediate geographical neighbours in South Asia. Allele frequency-based analyses likely support the existence of a specific ancestry component in the Himalayan and adjoining populations. The admixture time estimate suggests a recent westward migration of populations living to the East of the Himalaya. Furthermore, the uniparental marker analysis among the Himalayan and adjoining populations reveal the presence of East, Southeast and South Asian genetic signatures. Interestingly, we observed an antagonistic association of Y chromosomal haplogroups O3 and D clines with the longitudinal distance. Thus, we summarise that studying the Himalayan and adjoining populations is essential for a comprehensive reconstruction of the human evolutionary and ethnolinguistic history of eastern Eurasia.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Ásia , Povo Asiático , Etnicidade/genética , Frequência do Gene , Haplótipos/genética , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único/genética
11.
Proc Natl Acad Sci U S A ; 111(3): 1043-8, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24402169

RESUMO

Does the paucity of empirical evidence of sympatric speciation in nature reflect reality, despite theoretical support? Or is it due to inappropriate searches in nature with overly restrictive assumptions and an incorrect null hypothesis? Spiny mice, Acomys, described here at Evolution Canyon (EC) incipiently and sympatrically speciate owing to microclimatic interslope divergence. The opposite slopes at EC vary dramatically, physically and biotically, representing the dry and hot south-facing slope savannoid-African continent ["African" slope (AS)], abutting with the north-facing slope forested south-European continent ["European" slope (ES)]. African-originated spiny mice, of the Acomys cahirinus complex, colonized Israel 30,000 y ago based on fossils. Genotypically, we showed significantly higher genetic diversity of mtDNA and amplified fragment length polymorphism of Acomys on the AS compared with the ES. This is also true regionally across Israel. In complete mtDNA, 25% of the haplotypes at EC were slope-biased. Phenotypically, the opposite slope's populations also showed adaptive morphology, physiology, and behavior divergence paralleling regional populations across Israel. Preliminary tests indicate slope-specific mate choices. Colonization of Acomys at the EC first occurred on the AS and then moved to the ES. Strong slope-specific natural selection (both positive and negative) overrules low interslope gene flow. Both habitat slope selection and mate choices suggest ongoing incipient sympatric speciation. We conclude that Acomys at the EC is ecologically and genetically adaptively, incipiently, sympatrically speciating on the ES owing to adaptive microclimatic natural selection.


Assuntos
Especiação Genética , Murinae/genética , Simpatria , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , DNA Mitocondrial/genética , Ecossistema , Fluxo Gênico , Variação Genética , Genótipo , Haplótipos , Israel , Cariotipagem , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Fenótipo , Filogenia , Especificidade da Espécie
12.
Proc Natl Acad Sci U S A ; 110(7): 2587-92, 2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23359700

RESUMO

Sympatric speciation has been controversial since it was first proposed as a mode of speciation. Subterranean blind mole rats (Spalacidae) are considered to speciate allopatrically or peripatrically. Here, we report a possible incipient sympatric adaptive ecological speciation in Spalax galili (2n = 52). The study microsite (0.04 km(2)) is sharply subdivided geologically, edaphically, and ecologically into abutting barrier-free ecologies divergent in rock, soil, and vegetation types. The Pleistocene Alma basalt abuts the Cretaceous Senonian Kerem Ben Zimra chalk. Only 28% of 112 plant species were shared between the soils. We examined mitochondrial DNA in the control region and ATP6 in 28 mole rats from basalt and in 14 from chalk habitats. We also sequenced the complete mtDNA (16,423 bp) of four animals, two from each soil type. Remarkably, the frequency of all major haplotype clusters (HC) was highly soil-biased. HCI and HCII are chalk biased. HC-III was abundant in basalt (36%) but absent in chalk; HC-IV was prevalent in basalt (46.5%) but was low (20%) in chalk. Up to 40% of the mtDNA diversity was edaphically dependent, suggesting constrained gene flow. We identified a homologous recombinant mtDNA in the basalt/chalk studied area. Phenotypically significant divergences differentiate the two populations, inhabiting different soils, in adaptive oxygen consumption and in the amount of outside-nest activity. This identification of a possible incipient sympatric adaptive ecological speciation caused by natural selection indirectly refutes the allopatric alternative. Sympatric ecological speciation may be more prevalent in nature because of abundant and sharply abutting divergent ecologies.


Assuntos
Adaptação Biológica/fisiologia , Ecossistema , Especiação Genética , Variação Genética , Solo/análise , Spalax/genética , Adaptação Biológica/genética , Análise de Variância , Animais , Sequência de Bases , Biologia Computacional , DNA Mitocondrial/genética , Genética Populacional , Haplótipos/genética , Israel , Dados de Sequência Molecular , Consumo de Oxigênio/fisiologia , Seleção Genética , Análise de Sequência de DNA , Spalax/fisiologia , Especificidade da Espécie
13.
PLoS One ; 7(1): e30043, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22253871

RESUMO

The concept of climate variability facilitating adaptive radiation supported by the "Court Jester" hypothesis is disputed by the "Red Queen" one, but the prevalence of one or the other might be scale-dependent. We report on a detailed, comprehensive phylo-geographic study on the ∼4 kb mtDNA sequence in underground blind mole rats of the family Spalacidae (or subfamily Spalacinae) from the East Mediterranean steppes. Our study aimed at testing the presence of periodicities in branching patterns on a constructed phylogenetic tree and at searching for congruence between branching events, tectonic history and paleoclimates. In contrast to the strong support for the majority of the branching events on the tree, the absence of support in a few instances indicates that network-like evolution could exist in spalacids. In our tree, robust support was given, in concordance with paleontological data, for the separation of spalacids from muroid rodents during the first half of the Miocene when open, grass-dominated habitats were established. Marine barriers formed between Anatolia and the Balkans could have facilitated the separation of the lineage "Spalax" from the lineage "Nannospalax" and of the clade "leucodon" from the clade "xanthodon". The separation of the clade "ehrenbergi" occurred during the late stages of the tectonically induced uplift of the Anatolian high plateaus and mountains, whereas the separation of the clade "vasvarii" took place when the rapidly uplifting Taurus mountain range prevented the Mediterranean rainfalls from reaching the Central Anatolian Plateau. The separation of Spalax antiquus and S. graecus occurred when the southeastern Carpathians were uplifted. Despite the role played by tectonic events, branching events that show periodicity corresponding to 400-kyr and 100-kyr eccentricity bands illuminate the important role of orbital fluctuations on adaptive radiation in spalacids. At the given scale, our results supports the "Court Jester" hypothesis over the "Red Queen" one.


Assuntos
Evolução Biológica , Cegueira/genética , Mudança Climática , Ratos-Toupeira/genética , Animais , Sequência de Bases , DNA Mitocondrial/genética , Geografia , Funções Verossimilhança , Região do Mediterrâneo , Dados de Sequência Molecular , Filogenia , Fatores de Tempo
14.
Hum Mutat ; 29(12): 1387-91, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18629826

RESUMO

The biological role of the mitochondrial DNA (mtDNA) control region in mtDNA replication remains unclear. In a worldwide survey of mtDNA variation in the general population, we have identified a novel large control region deletion spanning positions 16154 to 16307 (m.16154_16307del154). The population prevalence of this deletion is low, since it was only observed in 1 out of over 120,000 mtDNA genomes studied. The deletion is present in a nonheteroplasmic state, and was transmitted by a mother to her two sons with no apparent past or present disease conditions. The identification of this large deletion in healthy individuals challenges the current view of the control region as playing a crucial role in the regulation of mtDNA replication, and supports the existence of a more complex system of multiple or epigenetically-determined replication origins.


Assuntos
Replicação do DNA , DNA Mitocondrial/genética , Região de Controle de Locus Gênico , Deleção de Sequência , Sequência de Bases , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Mitocôndrias/genética , Dados de Sequência Molecular
15.
PLoS One ; 3(5): e2105, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-18461126

RESUMO

BACKGROUND: Phylogenetic mitochondrial DNA haplogroups are highly partitioned across global geographic regions. A unique exception is the X haplogroup, which has a widespread global distribution without major regions of distinct localization. PRINCIPAL FINDINGS: We have examined mitochondrial DNA sequence variation together with Y-chromosome-based haplogroup structure among the Druze, a religious minority with a unique socio-demographic history residing in the Near East. We observed a striking overall pattern of heterogeneous parental origins, consistent with Druze oral tradition, together with both a high frequency and a high diversity of the mitochondrial DNA (mtDNA) X haplogroup within a confined regional subpopulation. Furthermore demographic modeling indicated low migration rates with nearby populations. CONCLUSIONS: These findings were enabled through the use of a paternal kindred based sampling approach, and suggest that the Galilee Druze represent a population isolate, and that the combination of a high frequency and diversity of the mtDNA X haplogroup signifies a phylogenetic refugium, providing a sample snapshot of the genetic landscape of the Near East prior to the modern age.


Assuntos
Etnicidade/genética , Refugiados , Consanguinidade , DNA Mitocondrial/genética , Feminino , Frequência do Gene , Variação Genética , Genética Populacional , Haplótipos , Humanos , Israel , Masculino , Oriente Médio
16.
PLoS One ; 3(4): e2062, 2008 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18446216

RESUMO

The history of the Jewish Diaspora dates back to the Assyrian and Babylonian conquests in the Levant, followed by complex demographic and migratory trajectories over the ensuing millennia which pose a serious challenge to unraveling population genetic patterns. Here we ask whether phylogenetic analysis, based on highly resolved mitochondrial DNA (mtDNA) phylogenies can discern among maternal ancestries of the Diaspora. Accordingly, 1,142 samples from 14 different non-Ashkenazi Jewish communities were analyzed. A list of complete mtDNA sequences was established for all variants present at high frequency in the communities studied, along with high-resolution genotyping of all samples. Unlike the previously reported pattern observed among Ashkenazi Jews, the numerically major portion of the non-Ashkenazi Jews, currently estimated at 5 million people and comprised of the Moroccan, Iraqi, Iranian and Iberian Exile Jewish communities showed no evidence for a narrow founder effect, which did however characterize the smaller and more remote Belmonte, Indian and the two Caucasus communities. The Indian and Ethiopian Jewish sample sets suggested local female introgression, while mtDNAs in all other communities studied belong to a well-characterized West Eurasian pool of maternal lineages. Absence of sub-Saharan African mtDNA lineages among the North African Jewish communities suggests negligible or low level of admixture with females of the host populations among whom the African haplogroup (Hg) L0-L3 sub-clades variants are common. In contrast, the North African and Iberian Exile Jewish communities show influence of putative Iberian admixture as documented by mtDNA Hg HV0 variants. These findings highlight striking differences in the demographic history of the widespread Jewish Diaspora.


Assuntos
Emigração e Imigração , Efeito Fundador , Genealogia e Heráldica , Judeus/genética , Mães , Filogenia , Sequência de Bases , DNA Mitocondrial/genética , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA
17.
Am J Hum Genet ; 78(3): 487-97, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16404693

RESUMO

Both the extent and location of the maternal ancestral deme from which the Ashkenazi Jewry arose remain obscure. Here, using complete sequences of the maternally inherited mitochondrial DNA (mtDNA), we show that close to one-half of Ashkenazi Jews, estimated at 8,000,000 people, can be traced back to only 4 women carrying distinct mtDNAs that are virtually absent in other populations, with the important exception of low frequencies among non-Ashkenazi Jews. We conclude that four founding mtDNAs, likely of Near Eastern ancestry, underwent major expansion(s) in Europe within the past millennium.


Assuntos
DNA Mitocondrial/genética , Efeito Fundador , Judeus/classificação , Judeus/etnologia , Filogenia , Sequência de Bases , Feminino , Humanos , Judeus/genética , Masculino , Dados de Sequência Molecular
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