Caracterização da distribuição de alelos de loci STR do cromossomo Y com elevada taxa de mutação em uma amostra populacional do Rio de Janeiro

Marcadores genéticos presentes no cromossomo Y, como os microssatélites (Y-STRs) e polimorfismos de único nucleotídeo (Y-SNPs) são utilizados na caracterização de linhagens masculinas, visto que são transmitidos às gerações seguintes sem alterações, a menos que ocorram mutações (Singh et al., 2011; Mitchell & Hammer, 1996; Butler, 2009). Por isso, esses marcadores são amplamente empregados em diversas situações, destacando-se o uso constante dos Y-STRs na genética forense por apresentarem alta capacidade de discriminar linhagens. Recentemente, foram descritos 13 marcadores com taxas de mutação substancialmente superiores àquelas verificadas para loci STR do cromossomo Y, denominados Rapidly Mutating (RM) Y-STRs (Ballantyne et al., 2010; Kayser et al., 2012). Devido às taxas de mutação elevadas, os RM-YSTRs apresentam maior eficiência na discriminação entre indivíduos proximamente relacionados, pertencentes à mesma linhagem patrilínea. O presente trabalho buscou aprofundar o conhecimento acerca das características populacionais e mutacionais dos loci RM-YSTRs em amostra do Rio de Janeiro, contribuindo com estudos desta natureza na população brasileira. Realizou-se a análise de 13 loci do cromossomo Y em 258 indivíduos do sexo masculino, compondo 129 pares de pais e filhos, nascidos no estado do Rio de Janeiro. O DNA das amostras foi extraído, conforme os protocolos vigentes na rotina do LDD-UERJ. As sequências genéticas de interesse foram amplificadas pela técnica de reação em cadeira da polimerase (PCR) através da realização de três PCR multiplex, cujos produtos de amplificação foram separados por eletroforese em sequenciador automático ABI-3500 (Applied Biosystems). Para os pares pai/filho que apresentaram haplótipos mutados, empregou-se a técnica de sequenciamento para confirmação das mutações. Os loci RM-YSTR geraram um poder de discriminação de 1,0 na amostra analisada, o que significa que todos os 129 indivíduos da amostra populacional apresentaram haplótipos diferentes para tais marcadores, com frequências de 0,0077 e diversidade haplotípica igual a 1. Além disso, foram obtidos valores elevados de diversidade gênica para os 13 marcadores. A análise de distância genética e os resultados de AMOVA baseados nos valores de Fst demonstraram que os RM-YSTR não indicam subdivisão populacional e traços ancestrais comuns. Tais valores estão associados às elevadas taxas de mutação encontradas, cuja média foi de 2,11 x 10-2. Foi possível observar que os loci RM-YSTR são muito discriminativos na amostra miscigenada analisada, além de terem maior capacidade de diferenciar indivíduos do que outros conjuntos de marcadores normalmente usados em estudos populacionais e análises forenses. Sendo assim, é possível concluir que os marcadores RM-YSTR são promissores para discriminar indivíduos da mesma linhagem patrilínea, visto que devido às suas elevadas taxas mutacionais e poder de discriminação, são capazes de diferenciar indivíduos de maneira mais eficiente do que os outros conjuntos de STR. Porém, é necessário maior número de estudos para melhor caracterização destes loci em diferentes populações.

Annual report 2006 - North Pacific Marine Science Organization (PICES). Fifteenth meeting, Yokohama, Japan, October 13-22, 2006

◾ Report of Opening Session (p. 1) ◾ Report of Governing Council (p. 15) ◾ Report of the Finance and Administration Committee (p. 47) ◾ Reports of Science Board and Committees: Science Board Inter-sessional Meeting (p. 63); Science Board (p. 73); Biological Oceanography Committee (p. 87); Fishery Science Committee (p. 95); Marine Environmental Quality Committee (p. 105); MONITOR Technical Committee (p. 115); Physical Oceanography and Climate Committee (p. 125); Technical Committee on Data Exchange (p. 133) ◾ Reports of Sections, Working and Study Groups: Section on Carbon and Climate (p. 139); Section on Ecology of Harmful Algal Blooms in the North Pacific (p. 143); Working Group 18 on Mariculture in the 21st Century - The Intersection Between Ecology, Socio-economics and Production (p. 147); Working Group 19 on Ecosystem-Based Management Science and its Application to the North Pacific (p. 151); Working Group 20 on Evaluations of Climate Change Projections (p. 157); Working Group 21 on Non-indigenous Aquatic Species (p. 159); Study Group to Develop a Strategy for GOOS (p. 165) ◾ Reports of the Climate Change and Carrying Capacity Scientific Program: Implementation Panel on the CCCC Program (p. 169); CFAME Task Team (p. 175); MODEL Task Team (p. 181) ◾ Reports of Advisory Panels: Advisory Panel for a CREAMS/PICES Program in East Asian Marginal Seas (p. 187); Advisory Panel on Continuous Plankton Recorder Survey in the North Pacific (p. 193); Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (p. 197); Advisory Panel on Marine Birds and Mammals (p. 201); Advisory Panel on Micronekton Sampling Inter-calibration Experiment (p. 205) ◾ Summary of Scientific Sessions and Workshops (p. 209) ◾ Membership List (p. 259) ◾ List of Participants (p. 277) ◾ List of PICES Acronyms (p. 301) ◾ List of Acronyms (p. 303)

Report of the Workshop on Blue Crab Stock Dynamics in Chesapeake Bay, December 13-15, 1982, Chesapeake Biological Laboratory

This workshop was convened to begin building a foundation of understanding for developing and evaluating proposed measures for the rational management of the blue crab fishery in Chesapeake Bay. Our goal was to generate a summary of knowledge of blue crab stock dynamics. Specifically, we intended to address, and hoped to estimate, the basic parameters of an exploited stock - growth, mortality, natality, migration rates, sex ratios and abundance. In one sense these objectives were simply a means for organizing our discussions. A second objective was to compile at the workshop pertinent data held by the major research institutions on Chesapeake Bay so all participants could see the kinds and extent of existing data. As with many stock assessment problems, tailoring an estimating procedure around known existing data can be more productive than deciding on a procedure and then trying to find the required data in someone else's files. Authors of papers contributed to the report: B.S. Hester and P.R. Mundy (p. 50); Qisheng Tang (p. 86); L. Eugene Cronin (p. 111); J.R. McConaugha (p. 128); Cluney Stagg and Phil Jones (p. 153).

Tropical forest history of the Ecuadorian Andes over the last 34,000 years: preliminary results from pollen and oxygen isotope analyses of Trident 163-13 from the eastern equatorial Pacific [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Pollen from the upper 2.75 m of a core taken 200 km west of the Golfo de Guayaquil, Ecuador (Trident 163-13, 3° S, 84° W, 3,000 m water depth) documents changes in Andean vegetation and climate of the Cordillera Occidental for ~17,000 years before and after the last glacial maximum.

Cruise report: regional assessment of ecosystem condition and stressor impacts along the northeastern Gulf of Mexico shelf; NOAA Ship Nancy Foster NF-10-09-RACOW (August 13-21, 2010)

This cruise report is a summary of a field survey conducted along the continental shelf of the northeastern Gulf of Mexico (GOM), encompassing 70,062 square kilometers of productive marine habitats located between the Mississippi Delta and Tampa Bay, August 13–21, 2010 on NOAA Ship Nancy Foster Cruise NF-10-09-RACOW. Synoptic sampling of multiple ecological indicators was conducted at each of 50 stations throughout these waters using a random probabilistic sampling design. At each station samples were collected for the analysis of benthic community structure and composition; concentrations of chemical contaminants (metals, pesticides, TPHs, PAHs, PCBs, PBDEs) in sediments and target demersal biota; sediment toxicity; nutrient and chlorophyll levels in the water column; and other basic habitat characteristics such as depth, salinity, temperature, dissolved oxygen, turbidity, pH, CDOM fluorescence, sediment grain size, and organic carbon content. Discrete water samples were collected just below the sea surface, in addition to any deeper subsurface depths where there was an occurrence of suspicious CDOM fluorescence signals, and analyzed for total BTEX/TPH and carcinogenic PAHs using immunoassay test kits. Other indicators of potential value from a human-dimension perspective were also recorded, including presence of any vessels, oil rigs, surface trash, visual oil sheens in sediments or water, marine mammals, or noxious/oily sediment odors. The overall purpose of the survey was to collect data to assess the status of ecosystem condition and potential stressor impacts throughout the region, based on these various indicators and corresponding management thresholds, and to provide this information as a baseline for determining how such conditions may be changing with time. In addition to the original project goals, both the scientific scope and general location of this project are relevant to addressing potential ecological impacts of the Deepwater Horizon oil spill. While sample analysis is still ongoing, a few preliminary results and observations are reported here. A final report will be completed once all data have been processed.