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Genome-wide association (GWA) studies have identified common variants that are associated with a variety of traits and diseases, but most studies have been performed in European-derived populations. Here, we describe the first genome-wide analyses of imputed genotype and copy number variants (CNVs) for anthropometric measures in African-derived populations: 1188 Nigerians from Igbo-Ora and Ibadan, Nigeria, and 743 African-Americans from Maywood, IL. To improve the reach of our study, we used imputation to estimate genotypes at approximately 2.1 million single-nucleotide polymorphisms (SNPs) and also tested CNVs for association. No SNPs or common CNVs reached a genome-wide significance level for association with height or body mass index (BMI), and the best signals from a meta-analysis of the two cohorts did not replicate in approximately 3700 African-Americans and Jamaicans. However, several loci previously confirmed in European populations showed evidence of replication in our GWA panel of African-derived populations, including variants near IHH and DLEU7 for height and MC4R for BMI. Analysis of global burden of rare CNVs suggested that lean individuals possess greater total burden of CNVs, but this finding was not supported in an independent European population. Our results suggest that there are not multiple loci with strong effects on anthropometric traits in African-derived populations and that sample sizes comparable to those needed in European GWA studies will be required to identify replicable associations. Meta-analysis of this data set with additional studies in African-ancestry populations will be helpful to improve power to detect novel associations.

Corals are known to contain a diverse microbiota; however, few studies have explicitly addressed the spatial variability of bacterial communities across individual, healthy coral colonies. This study applied culture-based and culture-independent methods to examine the spatial heterogeneity in bacterial communities in the mucus of 3 healthy Montastraea annularis colonies from Looe Key Reef, Florida Keys. Automated ribosomal intergenic spacer analysis (ARISA) results showed significant variability (up to 61% dissimilarity) in the composition of the total bacterial community at different locations only centimeters apart on individual coral colonies. Abundances of culturable Vibrio spp. determined by TCBS plating were highly variable across individual coral colonies, differing by up to 100-fold between different locations on the same colony. ARISA profiles indicated that intracolony variation rivaled intercolony differences in the composition of the culturable Vibrio community (i.e. types of culturable Vibrio spp. and their relative abundances). The high degree of spatial heterogeneity in coral-associated bacteria observed across individual colonies has implications for coral microbiology studies and coral restoration projects.KEY WORDS: Community profiling · ARISA · Bacteria · Coral · Spatial heterogeneity · Vibrio Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 426: [29][30][31][32][33][34][35][36][37][38][39][40] 2011 in bacterial community composition have been observed in bleached and diseased corals, with opportunists and pathogens present in these health-compromised states (Ritchie & Smith 1995, Kushmaro et al. 1997, Frias-Lopez et al. 2002, Pantos et al. 2003, Pantos & Bythell 2006, Ritchie 2006.The coral surface layers are extremely complex and dynamic (Ainsworth et al. 2006, Johnston & Rohwer 2007; however, few studies have examined spatial heterogeneity in coral-microbe associations across individual coral colonies. In diseased coral colonies, significant differences have been observed between the bacteria found in the healthy versus diseased portions of the colony (Frias-Lopez et al. 2002, Pantos et al. 2003, Breitbart et al. 2005, Gil-Agudelo et al. 2006, Pantos & Bythell 2006, Sekar et al. 2006. A limited number of studies have also demonstrated spatial variation in the bacterial community associated with healthy branching corals. Rohwer et al. (2002) demonstrated that bacterial communities were spatially structured on the branching coral Porites furcata, with specific bacterial taxa only found at the branch tips. In addition, bacterial community analysis in 6 replicate tissue samples from healthy Pocillopora damicornis colonies revealed spatial heterogeneity across some coral colonies (Bourne & Munn 2005), although some bacteria were uniformly found throughout an individual coral colony. Hansson et al. (2009) also demonstrated that the cold water coral Madrepora oculata exhibited spatial variation of bacterial communities within and among co...

A number of captive sandtiger sharks (Carcharias taurus) in public aquaria have developed spinal deformities over the past decade, ranging in severity from mild curvature to spinal fracture and severe subluxation. To determine the frequency and etiologic basis of this disease, U.S. public aquaria participated in a two-stage epidemiologic study of resident sharks: 1) a history and husbandry survey and 2) hematology, clinical chemistry, and radiography conducted during health exams. Eighteen aquaria submitted data, samples, or both from 73 specimens, including 19 affected sharks (26%). Sharks caught off the Rhode Island coast or by pound net were smaller at capture and demonstrated a higher prevalence of deformity than did larger sharks caught from other areas via hook and line. Relative to healthy sharks, affected sharks were deficient in zinc, potassium, and vitamins C and E. Capture and transport results lead to two likely etiologic hypotheses: 1) that the pound-net capture process induces spinal trauma that becomes exacerbated over time in aquarium environments or 2) that small (and presumably young) sharks caught by pound net are exposed to disease-promoting conditions (including diet or habitat deficiencies) in aquaria during the critical growth phase of their life history. The last hypothesis is further supported by nutrient deficiencies among affected sharks documented in this study; potassium, zinc, and vitamin C play critical roles in proper cartilage-collagen development and maintenance. These correlative findings indicate that public aquaria give careful consideration to choice of collection methods and size at capture and supplement diets to provide nutrients required for proper development and maintenance of cartilaginous tissue.

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