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1.
BMC Biol ; 19(1): 192, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34493285

RESUMEN

BACKGROUND: Long noncoding RNAs (lncRNAs) are important regulators in tumor progression. However, their biological functions and underlying mechanisms in hypoxia adaptation remain largely unclear. RESULTS: Here, we established a correlation between a Chr3q29-derived lncRNA gene and tongue squamous carcinoma (TSCC) by genome-wide analyses. Using RACE, we determined that two novel variants of this lncRNA gene are generated in TSCC, namely LINC00887_TSCC_short (887S) and LINC00887_TSCC_long (887L). RNA-sequencing in 887S or 887L loss-of-function cells identified their common downstream target as Carbonic Anhydrase IX (CA9), a gene known to be upregulated by hypoxia during tumor progression. Mechanistically, our results showed that the hypoxia-augmented 887S and constitutively expressed 887L functioned in opposite directions on tumor progression through the common target CA9. Upon normoxia, 887S and 887L interacted. Upon hypoxia, the two variants were separated. Each RNA recognized and bound to their responsive DNA cis-acting elements on CA9 promoter: 887L activated CA9's transcription through recruiting HIF1α, while 887S suppressed CA9 through DNMT1-mediated DNA methylation. CONCLUSIONS: We provided hypoxia-permitted functions of two antagonistic lncRNA variants to fine control the hypoxia adaptation through CA9.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Lengua , Anhidrasa Carbónica IX/genética , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Estudio de Asociación del Genoma Completo , Humanos , Hipoxia/genética , ARN Largo no Codificante/genética , Lengua , Neoplasias de la Lengua/genética
2.
Genome Res ; 28(11): 1601-1610, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30352807

RESUMEN

Centenarians (CENs) are excellent subjects to study the mechanisms of human longevity and healthy aging. Here, we analyzed the transcriptomes of 76 centenarians, 54 centenarian-children, and 41 spouses of centenarian-children by RNA sequencing and found that, among the significantly differentially expressed genes (SDEGs) exhibited by CENs, the autophagy-lysosomal pathway is significantly up-regulated. Overexpression of several genes from this pathway, CTSB, ATP6V0C, ATG4D, and WIPI1, could promote autophagy and delay senescence in cultured IMR-90 cells, while overexpression of the Drosophila homolog of WIPI1, Atg18a, extended the life span in transgenic flies. Interestingly, the enhanced autophagy-lysosomal activity could be partially passed on to their offspring, as manifested by their higher levels of both autophagy-encoding genes and serum beclin 1 (BECN1). In light of the normal age-related decline of autophagy-lysosomal functions, these findings provide a compelling explanation for achieving longevity in, at least, female CENs, given the gender bias in our collected samples, and suggest that the enhanced waste-cleaning activity via autophagy may serve as a conserved mechanism to prolong the life span from Drosophila to humans.


Asunto(s)
Autofagia/genética , Longevidad/genética , Transcriptoma , Anciano , Anciano de 80 o más Años , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Beclina-1/genética , Beclina-1/metabolismo , Catepsina B/genética , Catepsina B/metabolismo , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Femenino , Humanos , Lisosomas/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo
3.
Mol Biol Evol ; 36(8): 1643-1652, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31112995

RESUMEN

A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.


Asunto(s)
Genoma Humano , Genoma Mitocondrial , Ríos , Agricultura , China , Demografía , Humanos , Filogeografía
4.
RNA Biol ; 17(11): 1657-1665, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32635806

RESUMEN

Mouse and rats are staple model organisms that have been traditionally used for oncological studies; however, their short lifespan and highly prone to cancers limit their utilizationsin understanding the mechanisms of cancer resistance. In recent years, several studies of the non-standard long-lived mammalian species like naked mole rat (NMR) have provided new insights of mechanisms in natural anti-cancer. How long-lived species genetically maintain longevity and cancer-resistance remains largely elusive. To better understand the underlying anti-cancer mechanisms in long-lived mammals, we genome widely identified long noncoding RNA (lncRNA) transcripts of two longevous mammals, bowhead whale (BW, Balaena mysticetus) and Brandt's bat (BB, Myotis brandtii) and featured their sequence traits, expression patterns, and their correlations with cancer-resistance. Similar with naked mole rat (NMR, Heterocephalus glaber), the most long-lived rodent, BW and BB lncRNAs show low sequence conservation and dynamic expressions among tissues and physiological stages. By utilizing k-mers clustering, 75-136 of BW, BB and NMR lncRNAs were found in close relation (Pearson's r ≥0.9, p < 0.01) with human ageing diseases related lncRNAs (HAR-Lncs). In addition, we observed thousands of BB and BW lncRNAs strongly co-expressed (r > 0.8 or r <-0.8, p < 0.01) with potential tumour suppressors, indicating that lncRNAs are potentially involved in anti-cancer regulation in long-lived mammals. Our study provides the basis for lncRNA researches in perspectives of evolution and anti-cancer studies. Abbreviations: BW: bowhead whale; BB: Brandt's bat; NMR: naked mole rat; LLM: long-lived mammal; HTS: human tumour-suppressors; PTS: potential tumour suppressor; ARD: ageing related diseases; HAR-Lncs: lncRNAs that related with human ageing diseases; Kmer-lncs: lncRNAs in long-lived mammal species that corelated (Pearson'sr ≥0.9, p < 0.01) with the 10 HAR-Lncs by k-mers clustering; All-lncs: all the lncRNAs in long-lived mammal species; SDE-lncs: significant differentially expressed lncRNAs.


Asunto(s)
Resistencia a la Enfermedad/genética , Susceptibilidad a Enfermedades , Genómica , Mamíferos/genética , Neoplasias/genética , ARN Largo no Codificante/genética , Envejecimiento/genética , Animales , Evolución Molecular , Regulación de la Expresión Génica , Genes Supresores de Tumor , Predisposición Genética a la Enfermedad , Genoma , Genómica/métodos , Humanos , Longevidad/genética , Especificidad de Órganos/genética
5.
Yi Chuan ; 40(10): 814-824, 2018 Oct 20.
Artículo en Zh | MEDLINE | ID: mdl-30369466

RESUMEN

East Asia is widely concerned as one of the important places for the dispersal and evolution of the Anatomically Modern Human (AMH). How the diverse ethnic groups in East Asia originated and diversified is also widely focused by different disciplines of Anthropology. The adoption of genetic data had provided new clues for reconstructing the genetic history of East Asian populations. Genetic studies supported the hypothesis that the AMHs originated from Africa's Homo sapiens at about 200 kilo years ago (kya) and then migrated out of Africa at ~100 kya, followed by expansions into the whole East Asia since their arrival in Southern East Asia at 5~6 kya along the coastal route. Early Homo Sapiens might have genetic contribution to the non-African AMHs. Early settlement, cultural assimilation, population migration and genetic exchanges are crucial in the origination and evolution of East Asia populations. Previous studies made detailed analysis for the genetic history of East Asian populations, which largely resolved the longstanding divergence between archaeology and history. However, this needs further verification by whole-genome sequencing and ancient DNA studies. Here we briefly reviewed the progresses of genetic studies in exploring the population origin, dispersal and diversification in East Asia, which improved understanding of the evolution of East Asian populations. We also prospected the future of genetic studies in revealing the prehistory of East Asians.


Asunto(s)
Pueblo Asiatico/genética , Genética de Población , Asia , Evolución Molecular , Genética Humana , Humanos , Filogenia
6.
J Hum Genet ; 61(8): 721-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27098877

RESUMEN

In the past decades, the Tai people are increasingly being focused by genetic studies. However, a systematic genetic study of the whole Tai people is still lacking, thus making the population structure as well as the demographic history of this group uninvestigated from genetic perspective. Here we extensively analyzed the variants of hypervariable segments I and II (HVS-I and HVS-II) of mitochondrial DNA (mtDNA) of 719 Tai samples from 19 populations, covering virtually all of the current Tai people's residences. We observed a general close genetic affinity of the Tai people, reflecting a common origin of this group. Taken into account the phylogeographic analyses of their shared components, including haplogroups F1a, M7b and B5a, our study supported a southern Yunnan origin of the Tai people, consistent with the historical records. In line with their diverse cultures and languages, substantial genetic divergences can be observed among different Tai populations that could be attributable to assimilation of maternal components from neighboring populations. Our study further implied the advent of rice agriculture in Mainland Southeast Asia at ∼5 kya (kilo years ago) had greatly promoted the population expansion of the Tai people.


Asunto(s)
Pueblo Asiatico/genética , ADN Mitocondrial/genética , Variación Genética , Genética de Población , Asia Sudoriental , Análisis por Conglomerados , Geografía , Haplotipos , Humanos , Dinámica Poblacional , Análisis de Secuencia de ADN
7.
Aging Cell ; 23(7): e14163, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38566438

RESUMEN

The transition from ordered to noisy is a significant epigenetic signature of aging and age-related disease. As a paradigm of healthy human aging and longevity, long-lived individuals (LLI, >90 years old) may possess characteristic strategies in coping with the disordered epigenetic regulation. In this study, we constructed high-resolution blood epigenetic noise landscapes for this cohort by a methylation entropy (ME) method using whole genome bisulfite sequencing (WGBS). Although a universal increase in global ME occurred with chronological age in general control samples, this trend was suppressed in LLIs. Importantly, we identified 38,923 genomic regions with LLI-specific lower ME (LLI-specific lower entropy regions, for short, LLI-specific LERs). These regions were overrepresented in promoters, which likely function in transcriptional noise suppression. Genes associated with LLI-specific LERs have a considerable impact on SNP-based heritability of some aging-related disorders (e.g., asthma and stroke). Furthermore, neutrophil was identified as the primary cell type sustaining LLI-specific LERs. Our results highlight the stability of epigenetic order in promoters of genes involved with aging and age-related disorders within LLI epigenomes. This unique epigenetic feature reveals a previously unknown role of epigenetic order maintenance in specific genomic regions of LLIs, which helps open a new avenue on the epigenetic regulation mechanism in human healthy aging and longevity.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Envejecimiento Saludable , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Envejecimiento/genética , Metilación de ADN/genética , Pueblos del Este de Asia/genética , Entropía , Envejecimiento Saludable/genética , Longevidad/genética
8.
Aging Cell ; 23(1): e13916, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37400997

RESUMEN

Somatic mutations accumulate with age and are associated closely with human health, their characterization in longevity cohorts remains largely unknown. Here, by analyzing whole genome somatic mutation profiles in 73 centenarians and 51 younger controls in China, we found that centenarian genomes are characterized by a markedly skewed distribution of somatic mutations, with many genomic regions being specifically conserved but displaying a high function potential. This, together with the observed more efficient DNA repair ability in the long-lived individuals, supports the existence of key genomic regions for human survival during aging, with their integrity being of essential to human longevity.


Asunto(s)
Centenarios , Longevidad , Anciano de 80 o más Años , Humanos , Longevidad/genética , Envejecimiento/genética , Mutación/genética , Genómica
9.
Mol Biol Evol ; 29(4): 1255-61, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22130971

RESUMEN

In accordance with the hypothesis that cancer formation is a process of somatic evolution driven by natural selection, signature of positive selection has been detected on a number of cancer-related nuclear genes. It remains, however, controversial whether a similar selective pressure has also acted on mitochondrial DNA (mtDNA), a small molecule in mitochondrion that may play an important role in tumorigenesis by altering oxidative phosphorylation. To better understand the mutational pattern on cancerous mtDNA and decipher the genetic signature left by natural selection, a total of 186 entire mitochondrial genomes of cancerous and adjacent normal tissues from 93 esophageal cancer patients were obtained and extensively studied. Our results revealed that the observed mutational pattern on the cancerous mtDNAs might be best explained as relaxation of negative selection. Taking into account an additional 1,235 cancerous (nearly) complete mtDNA sequences retrieved from the literature, our results suggested that the relaxed selective pressure was the most likely explanation for the accumulation of mtDNA variation in different types of cancer. This notion is in good agreement with the observation that aerobic glycolysis, instead of mitochondrial respiration, plays the key role in generating energy in cancer cells. Furthermore, our study provided solid evidence demonstrating that problems in some of the published cancerous mtDNA data adequately explained the previously contradictory conclusions about the selective pressure on cancer mtDNA, thus serving as a paradigm emphasizing the importance of data quality in affecting our understanding on the role of mtDNA in tumorigenesis.


Asunto(s)
ADN Mitocondrial/genética , Neoplasias Esofágicas/genética , Genoma Mitocondrial , Selección Genética , Secuencia de Bases , Bases de Datos Genéticas , Neoplasias Esofágicas/química , Humanos , Datos de Secuencia Molecular , Mutación , Filogenia
10.
J Hum Genet ; 58(12): 780-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24108366

RESUMEN

The purpose of the present study was to identify mitochondrial DNA (mtDNA) polymorphisms and rare variants that associate with elite Japanese athletic status. Subjects comprised 185 elite Japanese athletes who had represented Japan at international competitions (that is, 100 endurance/middle-power athletes: EMA; 85 sprint/power athletes: SPA) and 672 Japanese controls (CON). The entire mtDNA sequences (16 569 bp) were analyzed by direct sequencing. Nucleotide variants were detected at 1488 sites in the 857 entire mtDNA sequences. A total of 311 variants were polymorphisms (minor allele frequency 1% in CON), and the frequencies of these polymorphisms were compared among the three groups. The EMA displayed excess of seven polymorphisms, including subhaplogroup D4e2- and D4g-specific polymorphisms, compared with CON (P<0.05), whereas SPA displayed excess of three polymorphisms and dearth of nine polymorphisms, including haplogroup G- and subhaplogroup G2a-specific polymorphisms, compared with CON (P<0.05). The frequencies of 10 polymorphisms, including haplogroup G- and subhaplogroup G2a-specific polymorphisms, were different between EMA and SPA (P<0.05): although none of these polymorphisms differed significantly between groups after correcting for multiple comparison (false discovery rate q-value 0.05). The number of rare variants in the 12S ribosomal RNA and NADH dehydrogenase subunit I genes were also higher in SPA than in CON (P<0.05). Analysis of the entire mtDNA of elite Japanese athletes revealed several haplogroup- and subhaplogroup-specific polymorphisms to be potentially associated with elite Japanese athletic status.


Asunto(s)
Pueblo Asiatico/genética , Rendimiento Atlético/fisiología , ADN Mitocondrial/genética , Variación Genética/genética , Mitocondrias/genética , Atletas , Estudios de Casos y Controles , Femenino , Haplotipos/genética , Humanos , Masculino , Polimorfismo Genético
11.
Metabolites ; 13(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36837790

RESUMEN

Glioblastoma (GBM) is one of the most aggressive forms of cancer. Although IDH1 mutation indicates a good prognosis and a potential target for treatment, most GBMs are IDH1 wild-type. Identifying additional molecular markers would help to generate personalized therapies and improve patient outcomes. Here, we used our recently developed metabolic modeling method (genome-wide precision metabolic modeling, GPMM) to investigate the metabolic profiles of GBM, aiming to identify additional novel molecular markers for this disease. We systematically analyzed the metabolic reaction profiles of 149 GBM samples lacking IDH1 mutation. Forty-eight reactions showing significant association with prognosis were identified. Further analysis indicated that the purine recycling, nucleotide interconversion, and folate metabolism pathways were the most robust modules related to prognosis. Considering the three pathways, we then identified the most significant GBM type for a better prognosis, namely N+P-. This type presented high nucleotide interconversion (N+) and low purine recycling (P-). N+P--type exhibited a significantly better outcome (log-rank p = 4.7 × 10-7) than that of N-P+. GBM patients with the N+P--type had a median survival time of 19.6 months and lived 65% longer than other GBM patients. Our results highlighted a novel molecular type of GBM, which showed relatively high frequency (26%) in GBM patients lacking the IDH1 mutation, and therefore exhibits potential in GBM prognostic assessment and personalized therapy.

12.
Aging Dis ; 14(4): 1374-1389, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37163432

RESUMEN

Aging is characterized by persistent low-grade systematic inflammation, which is largely responsible for the occurrence of various age-associated diseases. We and others have previously reported that long-lived people (such as centenarians) can delay the onset of or even escape certain major age-related diseases. Here, by screening blood transcriptome and inflammatory profiles, we found that long-lived individuals had a relatively lower inflammation level (IL6, TNFα), accompanied by up-regulation of activating transcription factor 7 (ATF7). Interestingly, ATF7 expression was gradually reduced during cellular senescence. Loss of ATF7 induced cellular senescence, while overexpression delayed senescence progress and senescence-associated secretory phenotype (SASP) secretion. We showed that the anti-senescence effects of ATF7 were achieved by inhibiting nuclear factor kappa B (NF-κB) signaling and increasing histone H3K9 dimethylation (H3K9me2). In Caenorhabditis elegans, ATF7 overexpression significantly suppressed aging biomarkers and extended lifespan. Our findings suggest that ATF7 is a longevity-promoting factor that lowers cellular senescence and inflammation in long-lived individuals.

13.
Cell Rep ; 42(5): 112413, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37164007

RESUMEN

Although it is widely recognized that the ancestors of Native Americans (NAs) primarily came from Siberia, the link between mitochondrial DNA (mtDNA) lineage D4h3a (typical of NAs) and D4h3b (found so far only in East China and Thailand) raises the possibility that the ancestral sources for early NAs were more variegated than hypothesized. Here, we analyze 216 contemporary (including 106 newly sequenced) D4h mitogenomes and 39 previously reported ancient D4h data. The results reveal two radiation events of D4h in northern coastal China, one during the Last Glacial Maximum and the other within the last deglaciation, which facilitated the dispersals of D4h sub-branches to different areas including the Americas and the Japanese archipelago. The coastal distributions of the NA (D4h3a) and Japanese lineages (D4h1a and D4h2), in combination with the Paleolithic archaeological similarities among Northern China, the Americas, and Japan, lend support to the coastal dispersal scenario of early NAs.


Asunto(s)
Genoma Mitocondrial , Humanos , Japón , Américas , China , ADN Mitocondrial/genética , Haplotipos/genética , Filogenia
14.
Hum Mutat ; 33(9): 1352-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22581690

RESUMEN

The Human Variome Project (HVP) is a global effort to collect and curate all human genetic variation affecting health. Mutations of mitochondrial DNA (mtDNA) are an important cause of neurogenetic disease in humans; however, identification of the pathogenic mutations responsible can be problematic. In this article, we provide explanations as to why and suggest how such difficulties might be overcome. We put forward a case in support of a new Locus Specific Mutation Database (LSDB) implemented using the Leiden Open-source Variation Database (LOVD) system that will not only list primary mutations, but also present the evidence supporting their role in disease. Critically, we feel that this new database should have the capacity to store information on the observed phenotypes alongside the genetic variation, thereby facilitating our understanding of the complex and variable presentation of mtDNA disease. LOVD supports fast queries of both seen and hidden data and allows storage of sequence variants from high-throughput sequence analysis. The LOVD platform will allow construction of a secure mtDNA database; one that can fully utilize currently available data, as well as that being generated by high-throughput sequencing, to link genotype with phenotype enhancing our understanding of mitochondrial disease, with a view to providing better prognostic information.


Asunto(s)
ADN Mitocondrial/genética , Bases de Datos de Ácidos Nucleicos , Sitios Genéticos , Mutación , Programas Informáticos , Biología Computacional/métodos , Análisis Mutacional de ADN/métodos , Análisis Mutacional de ADN/normas , Genoma Humano , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Almacenamiento y Recuperación de la Información , Internet , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/genética , Fosforilación Oxidativa , Fenotipo
15.
Mol Biol Evol ; 28(1): 513-22, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20713468

RESUMEN

In order to achieve a thorough coverage of the basal lineages in the Chinese matrilineal pool, we have sequenced the mitochondrial DNA (mtDNA) control region and partial coding region segments of 6,093 mtDNAs sampled from 84 populations across China. By comparing with the available complete mtDNA sequences, 194 of those mtDNAs could not be firmly assigned into the available haplogroups. Completely sequencing 51 representatives selected from these unclassified mtDNAs identified a number of novel lineages, including five novel basal haplogroups that directly emanate from the Eurasian founder nodes (M and N). No matrilineal contribution from the archaic hominid was observed. Subsequent analyses suggested that these newly identified basal lineages likely represent the genetic relics of modern humans initially peopling East Asia instead of being the results of gene flow from the neighboring regions. The observation that most of the newly recognized mtDNA lineages have already differentiated and show the highest genetic diversity in southern China provided additional evidence in support of the Southern Route peopling hypothesis of East Asians. Specifically, the enrichment of most of the basal lineages in southern China and their rather ancient ages in Late Pleistocene further suggested that this region was likely the genetic reservoir of modern humans after they entered East Asia.


Asunto(s)
Pueblo Asiatico/genética , ADN Mitocondrial/análisis , Etnicidad/genética , Genética de Población , Secuencia de Bases , Asia Oriental , Variación Genética , Haplotipos , Humanos , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
16.
J Hum Genet ; 57(4): 228-34, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22437208

RESUMEN

Himalayas was believed to be a formidably geographical barrier between South and East Asia. The observed high frequency of the East Eurasian paternal lineages in Nepal led some researchers to suggest that these lineages were introduced into Nepal from Tibet directly; however, it is also possible that the East Eurasian genetic components might trace their origins to northeast India where abundant East Eurasian maternal lineages have been detected. To trace the origin of the Nepalese maternal genetic components, especially those of East Eurasian ancestry, and then to better understand the role of the Himalayas in peopling Nepal, we have studied the matenal genetic composition extensively, especially the East Eurasian lineages, in Nepalese and its surrounding populations. Our results revealed the closer affinity between the Nepalese and the Tibetans, specifically, the Nepalese lineages of the East Eurasian ancestry generally are phylogenetically closer with the ones from Tibet, albeit a few mitochondrial DNA haplotypes, likely resulted from recent gene flow, were shared between the Nepalese and northeast Indians. It seems that Tibet was most likely to be the homeland for most of the East Eurasian in the Nepalese. Taking into account the previous observation on Y chromosome, now it is convincing that bearer of the East Eurasian genetic components had entered Nepal across the Himalayas around 6 kilo years ago (kya), a scenario in good agreement with the previous results from linguistics and archeology.


Asunto(s)
ADN Mitocondrial/genética , Genética de Población , Genoma Humano , Genoma Mitocondrial , Mitocondrias/genética , Pueblo Asiatico/genética , Cromosomas Humanos Y/genética , ADN Mitocondrial/clasificación , Flujo Génico , Haplotipos , Humanos , India , Nepal , Filogenia , Análisis de Componente Principal , Análisis de Secuencia de ADN , Tibet , Factores de Tiempo
17.
Proc Natl Acad Sci U S A ; 106(50): 21230-5, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19955425

RESUMEN

Due to its numerous environmental extremes, the Tibetan Plateau--the world's highest plateau--is one of the most challenging areas of modern human settlement. Archaeological evidence dates the earliest settlement on the plateau to the Late Paleolithic, while previous genetic studies have traced the colonization event(s) to no earlier than the Neolithic. To explore whether the genetic continuity on the plateau has an exclusively Neolithic time depth, we studied mitochondrial DNA (mtDNA) genome variation within 6 regional Tibetan populations sampled from Tibet and neighboring areas. Our results confirm that the vast majority of Tibetan matrilineal components can trace their ancestry to Epipaleolithic and Neolithic immigrants from northern China during the mid-Holocene. Significantly, we also identified an infrequent novel haplogroup, M16, that branched off directly from the Eurasian M founder type. Its nearly exclusive distribution in Tibetan populations and ancient age (>21 kya) suggest that M16 may represent the genetic relics of the Late Paleolithic inhabitants on the plateau. This partial genetic continuity between the Paleolithic inhabitants and the contemporary Tibetan populations bridges the results and inferences from archaeology, history, and genetics.


Asunto(s)
Emigración e Inmigración , Genoma Mitocondrial/genética , Paleontología , Secuencia de Bases , China , Efecto Fundador , Variación Genética , Historia Antigua , Humanos , Datos de Secuencia Molecular , Tibet
18.
BMC Biol ; 9: 2, 2011 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-21219640

RESUMEN

BACKGROUND: Archaeological studies have revealed a series of cultural changes around the Last Glacial Maximum in East Asia; whether these changes left any signatures in the gene pool of East Asians remains poorly indicated. To achieve deeper insights into the demographic history of modern humans in East Asia around the Last Glacial Maximum, we extensively analyzed mitochondrial DNA haplogroup M9a'b, a specific haplogroup that was suggested to have some potential for tracing the migration around the Last Glacial Maximum in East Eurasia. RESULTS: A total of 837 M9a'b mitochondrial DNAs (583 from the literature, while the remaining 254 were newly collected in this study) pinpointed from over 28,000 subjects residing across East Eurasia were studied here. Fifty-nine representative samples were further selected for total mitochondrial DNA sequencing so we could better understand the phylogeny within M9a'b. Based on the updated phylogeny, an extensive phylogeographic analysis was carried out to reveal the differentiation of haplogroup M9a'b and to reconstruct the dispersal histories. CONCLUSIONS: Our results indicated that southern China and/or Southeast Asia likely served as the source of some post-Last Glacial Maximum dispersal(s). The detailed dissection of haplogroup M9a'b revealed the existence of an inland dispersal in mainland East Asia during the post-glacial period. It was this dispersal that expanded not only to western China but also to northeast India and the south Himalaya region. A similar phylogeographic distribution pattern was also observed for haplogroup F1c, thus substantiating our proposition. This inland post-glacial dispersal was in agreement with the spread of the Mesolithic culture originating in South China and northern Vietnam.


Asunto(s)
Pueblo Asiatico/genética , ADN Mitocondrial/genética , Emigración e Inmigración , Variación Genética , Haplotipos , Asia Sudoriental , Evolución Molecular , Asia Oriental , Humanos , Filogenia , Filogeografía
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 14(8): 561-6, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-22898272

RESUMEN

This study reviews a case of mitochondrial respiratory chain complex I deficiency due to the 10191T>C mutation in mitochondrial ND3 gene. The previously healthy boy progressively presented with blepharoptosis, weakness, epilepsy and motor regression at age 6 years. Elevated blood lactate and pyruvate were observed. Brain magnetic resonance imaging showed symmetrical lesions in the basal ganglia. Leigh syndrome was thus confirmed. The protein from the mitochondria and genomic DNA of the boy and his parents was collected from peripheral blood leucocytes for the activity test for mitochondrial complex I to V and genetic analysis. The results showed the activity of complex I (33.1 nmol /min in 1 milligram mitochondrial protein) was lower than normal reference value (44.0±5.4 nmol /min in 1 milligram mitochondrial protein). The ratio of complex I to citrate synthase (19.8%) was also lower than normal reference value (48%±11%). The activities of complexes II to V were normal. 10191T>C mutation in ND3 gene of mitochondria was identified in the boy. 10191T>C mutation and complex I deficiency were not detected in his parents. At present, he is 16 years old, and of normal intelligence with spastic paralysis in both lower extremities after treatment. It is concluded that a Chinese boy with isolated complex I deficiency due to 10191T>C mutation in ND3 gene was firstly diagnosed by peripheral leukocytes mitochondrial respiratory chain enzyme assay and gene analysis. This study can provide clinical data for the nosogenesis of Leigh syndrome.


Asunto(s)
Complejo I de Transporte de Electrón/genética , Enfermedades Mitocondriales/genética , Mutación , Adolescente , Encéfalo/patología , Complejo I de Transporte de Electrón/deficiencia , Humanos , Enfermedad de Leigh/genética , Imagen por Resonancia Magnética , Masculino
20.
Genes (Basel) ; 13(5)2022 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-35627134

RESUMEN

Deep RNA sequencing of 164 blood samples collected from long-lived families was performed to investigate the expression patterns of circular RNAs (circRNAs). Unlike that observed in previous studies, circRNA expression in long-lived elderly individuals (98.3 ± 3.4 year) did not exhibit an age-accumulating pattern. Based on weighted circRNA co-expression network analysis, we found that longevous elders specifically gained eight but lost seven conserved circRNA-circRNA co-expression modules (c-CCMs) compared with normal elder controls (spouses of offspring of long-lived individuals, age = 59.3 ± 5.8 year). Further analysis showed that these modules were associated with healthy aging-related pathways. These results together suggest an important role of circRNAs in regulating human lifespan extension.


Asunto(s)
MicroARNs , ARN Circular , Anciano , Secuencia de Bases , Humanos , Longevidad/genética , MicroARNs/genética , Persona de Mediana Edad , ARN Circular/genética , Análisis de Secuencia de ARN
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