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121.
Genetic diversity in Puerto Rico and its implications for the peopling of the Island and the West Indies
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Miguel G. Vilar Carlalynne Melendez Akiva B. Sanders Akshay Walia Jill B. Gaieski Amanda C. Owings Theodore G. Schurr The Genographic Consortium 《American journal of physical anthropology》2014,155(3):352-368
Puerto Rico and the surrounding islands rest on the eastern fringe of the Caribbean's Greater Antilles, located less than 100 miles northwest of the Lesser Antilles. Puerto Ricans are genetic descendants of pre‐Columbian peoples, as well as peoples of European and African descent through 500 years of migration to the island. To infer these patterns of pre‐Columbian and historic peopling of the Caribbean, we characterized genetic diversity in 326 individuals from the southeastern region of Puerto Rico and the island municipality of Vieques. We sequenced the mitochondrial DNA (mtDNA) control region of all of the samples and the complete mitogenomes of 12 of them to infer their putative place of origin. In addition, we genotyped 121 male samples for 25 Y‐chromosome single nucleotide polymorphism and 17 STR loci. Approximately 60% of the participants had indigenous mtDNA haplotypes (mostly from haplogroups A2 and C1), while 25% had African and 15% European haplotypes. Three A2 sublineages were unique to the Greater Antilles, one of which was similar to Mesoamerican types, while C1b haplogroups showed links to South America, suggesting that people reached the island from the two distinct continental source areas. However, none of the male participants had indigenous Y‐chromosomes, with 85% of them instead being European/Mediterranean and 15% sub‐Saharan African in origin. West Eurasian Y‐chromosome short tandem repeat haplotypes were quite diverse and showed similarities to those observed in southern Europe, North Africa and the Middle East. These results attest to the distinct, yet equally complex, pasts for the male and female ancestors of modern day Puerto Ricans. Am J Phys Anthropol 155:352–368, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
122.
The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic rates (e.g., lower and upper limits of metabolic power output) present a method for elucidating the effects of ecological and evolutionary factors on the interface between physiology and life history in birds. In this paper we review variation in avian metabolic rates [basal metabolic rate (BMR; minimum normothermic metabolic rate), ... 相似文献
123.
Deletion 17q12 is a recurrent copy number variant that confers high risk of autism and schizophrenia
Moreno-De-Luca D;SGENE Consortium Mulle JG;Simons Simplex Collection Genetics Consortium Kaminsky EB Sanders SJ;GeneSTAR Myers SM Adam MP Pakula AT Eisenhauer NJ Uhas K Weik L Guy L Care ME Morel CF Boni C Salbert BA Chandrareddy A Demmer LA Chow EW Surti U Aradhya S Pickering DL Golden DM Sanger WG Aston E Brothman AR Gliem TJ Thorland EC Ackley T Iyer R Huang S Barber JC Crolla JA Warren ST Martin CL Ledbetter DH 《American journal of human genetics》2010,87(5):618-630
Autism spectrum disorders (ASD) and schizophrenia are neurodevelopmental disorders for which recent evidence indicates an important etiologic role for rare copy number variants (CNVs) and suggests common genetic mechanisms. We performed cytogenomic array analysis in a discovery sample of patients with neurodevelopmental disorders referred for clinical testing. We detected a recurrent 1.4 Mb deletion at 17q12, which harbors HNF1B, the gene responsible for renal cysts and diabetes syndrome (RCAD), in 18/15,749 patients, including several with ASD, but 0/4,519 controls. We identified additional shared phenotypic features among nine patients available for clinical assessment, including macrocephaly, characteristic facial features, renal anomalies, and neurocognitive impairments. In a large follow-up sample, the same deletion was identified in 2/1,182 ASD/neurocognitive impairment and in 4/6,340 schizophrenia patients, but in 0/47,929 controls (corrected p = 7.37 × 10−5). These data demonstrate that deletion 17q12 is a recurrent, pathogenic CNV that confers a very high risk for ASD and schizophrenia and show that one or more of the 15 genes in the deleted interval is dosage sensitive and essential for normal brain development and function. In addition, the phenotypic features of patients with this CNV are consistent with a contiguous gene syndrome that extends beyond RCAD, which is caused by HNF1B mutations only. 相似文献
124.
Hajo Grundmann David M. Aanensen Cees C. van den Wijngaard Brian G. Spratt Dag Harmsen Alexander W. Friedrich the European Staphylococcal Reference Laboratory Working Group? 《PLoS medicine》2010,7(1)
Background
Staphylococcus aureus is one of the most important human pathogens and methicillin-resistant variants (MRSAs) are a major cause of hospital and community-acquired infection. We aimed to map the geographic distribution of the dominant clones that cause invasive infections in Europe.Methods and Findings
In each country, staphylococcal reference laboratories secured the participation of a sufficient number of hospital laboratories to achieve national geo-demographic representation. Participating laboratories collected successive methicillin-susceptible (MSSA) and MRSA isolates from patients with invasive S. aureus infection using an agreed protocol. All isolates were sent to the respective national reference laboratories and characterised by quality-controlled sequence typing of the variable region of the staphylococcal spa gene (spa typing), and data were uploaded to a central database. Relevant genetic and phenotypic information was assembled for interactive interrogation by a purpose-built Web-based mapping application. Between September 2006 and February 2007, 357 laboratories serving 450 hospitals in 26 countries collected 2,890 MSSA and MRSA isolates from patients with invasive S. aureus infection. A wide geographical distribution of spa types was found with some prevalent in all European countries. MSSA were more diverse than MRSA. Genetic diversity of MRSA differed considerably between countries with dominant MRSA spa types forming distinctive geographical clusters. We provide evidence that a network approach consisting of decentralised typing and visualisation of aggregated data using an interactive mapping tool can provide important information on the dynamics of MRSA populations such as early signalling of emerging strains, cross border spread, and importation by travel.Conclusions
In contrast to MSSA, MRSA spa types have a predominantly regional distribution in Europe. This finding is indicative of the selection and spread of a limited number of clones within health care networks, suggesting that control efforts aimed at interrupting the spread within and between health care institutions may not only be feasible but ultimately successful and should therefore be strongly encouraged. Please see later in the article for the Editors'' Summary 相似文献125.
Jeffrey A. Anderson Li-Hua Ping Oliver Dibben Cassandra B. Jabara Leslie Arney Laura Kincer Yuyang Tang Marcia Hobbs Irving Hoffman Peter Kazembe Corbin D. Jones Persephone Borrow Susan Fiscus Myron S. Cohen Ronald Swanstrom and the Center for HIV/AIDS Vaccine Immunology 《PLoS pathogens》2010,6(8)
HIV-1 is present in anatomical compartments and bodily fluids. Most transmissions occur through sexual acts, making virus in semen the proximal source in male donors. We find three distinct relationships in comparing viral RNA populations between blood and semen in men with chronic HIV-1 infection, and we propose that the viral populations in semen arise by multiple mechanisms including: direct import of virus, oligoclonal amplification within the seminal tract, or compartmentalization. In addition, we find significant enrichment of six out of nineteen cytokines and chemokines in semen of both HIV-infected and uninfected men, and another seven further enriched in infected individuals. The enrichment of cytokines involved in innate immunity in the seminal tract, complemented with chemokines in infected men, creates an environment conducive to T cell activation and viral replication. These studies define different relationships between virus in blood and semen that can significantly alter the composition of the viral population at the source that is most proximal to the transmitted virus. 相似文献
126.
Tourette Syndrome Association International Consortium for Genetics 《American journal of human genetics》2007,80(2):265-272
Tourette disorder (TD) is a neuropsychiatric disorder with a complex mode of inheritance and is characterized by multiple waxing and waning motor and phonic tics. This article reports the results of the largest genetic linkage study yet undertaken for TD. The sample analyzed includes 238 nuclear families yielding 304 "independent" sibling pairs and 18 separate multigenerational families, for a total of 2,040 individuals. A whole-genome screen with the use of 390 microsatellite markers was completed. Analyses were completed using two diagnostic classifications: (1) only individuals with TD were included as affected and (2) individuals with either TD or chronic-tic (CT) disorder were included as affected. Strong evidence of linkage was observed for a region on chromosome 2p (-log P = 4.42, P = 3.8 x 10(-5) in the analyses that included individuals with TD or CT disorder as affected. Results in several other regions also provide moderate evidence (-log P >2.0) of additional susceptibility loci for TD. 相似文献
127.
128.
Peter C Bruford M Perez T Dalamitra S Hewitt G Erhardt G;ECONOGENE Consortium 《Animal genetics》2007,38(1):37-44
The population structure and genetic diversity of 57 European and Middle Eastern marginal and cosmopolitan sheep breeds from 15 countries were analysed by typing 31 microsatellite markers. Mean unbiased expected heterozygosities ranged from 0.63 in British Exmoor Horn to 0.77 in Albanian Ruda. South-eastern European and Middle-Eastern sheep breeds were significantly more variable than northwestern and western European breeds. An overall heterozygote deficiency (f) across all loci was observed (P < 0.001), while genetic differentiation (theta) was 5.7%. Principal component analysis and Bayesian model-based clustering indicate a south-east to north-west cline, but also revealed distinct groups of Middle-Eastern fat-tailed sheep, south-eastern European sheep and north-western/western European sheep. Within the last group, two less-distinct clusters comprised the Merino-type and Alpine breeds respectively. The incomplete demarcations of most clusters probably reflects cross-breeding and/or upgrading. 相似文献
129.
Hawkey CJ Talley NJ Scheiman JM Jones RH Långström G Naesdal J Yeomans ND;NASA/SPACE author group 《Arthritis research & therapy》2007,9(1):R17
Non-steroidal anti-inflammatory drugs (NSAIDs), including selective cyclo-oxygenase-2 (COX-2) inhibitors, cause upper gastrointestinal
(GI) symptoms that are relieved by treatment with esomeprazole. We assessed esomeprazole for maintaining long-term relief
of such symptoms. Six hundred and ten patients with a chronic condition requiring anti-inflammatory therapy who achieved relief
of NSAID-associated symptoms of pain, discomfort, or burning in the upper abdomen during two previous studies were enrolled
and randomly assigned into two identical, multicentre, parallel-group, placebo-controlled studies of esomeprazole 20 mg or
40 mg treatment (NASA2 [Nexium Anti-inflammatory Symptom Amelioration] and SPACE2 [Symptom Prevention by Acid Control with
Esomeprazole] studies; ClinicalTrials.gov identifiers NCT00241514 and NCT00241553, respectively) performed at various rheumatology,
gastroenterology, and primary care clinics. Four hundred and twenty-six patients completed the 6-month treatment period. The
primary measure was the proportion of patients with relapse of upper GI symptoms, recorded in daily diary cards, after 6 months.
Relapse was defined as moderate-to-severe upper GI symptoms (a score of more than or equal to 3 on a 7-grade scale) for 3
days or more in any 7-day period. Esomeprazole was significantly more effective than placebo in maintaining relief of upper
GI symptoms throughout 6 months of treatment. Life-table estimates (95% confidence intervals) of the proportion of patients
with relapse at 6 months (pooled population) were placebo, 39.1% (32.2% to 46.0%); esomeprazole 20 mg, 29.3% (22.3% to 36.2%)
(p = 0.006 versus placebo); and esomeprazole 40 mg, 26.1% (19.4% to 32.9%) (p = 0.001 versus placebo). Patients on either non-selective NSAIDs or selective COX-2 inhibitors appeared to benefit. The frequency
of adverse events was similar in the three groups. Esomeprazole maintains relief of NSAID-associated upper GI symptoms in
patients taking continuous NSAIDs, including selective COX-2 inhibitors. 相似文献