Publications by authors named "R Hamner"

Strong balancing selection on the major histocompatibility complex (MHC) can lead to different patterns in gene frequencies and neutral genomic variation within species. We investigated diversity and geographic structure of MHC genes DQA and DQB, as well as their inferred functional haplotypes, from 2 regional populations (East and West Coast) of the endangered Hector's dolphin (Cephalorhynchus hectori hectori) and the critically endangered Māui dolphin (Cephalorhynchus hectori maui) (West Coast, North Island), and contrasted these results with patterns from neutral microsatellites. The Māui had the lowest number of alleles for DQA (2) and DQB (3), consistent with strong genetic drift acting on this remnant population.

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The invasion of the western Atlantic Ocean by the Indo-Pacific red lionfish () has had devastating consequences for marine ecosystems. Estimating the number of colonizing lionfish can be useful in identifying the introduction pathway and can inform policy decisions aimed at preventing similar invasions. It is well-established that at least ten lionfish were initially introduced.

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The complementarity of historical and contemporary processes contributes to understanding the genetic structure of continuously distributed marine species with high dispersal capabilities. Cephalorhynchus eutropia, has a continuous coastal distribution with strong genetic differentiation identified by nuclear DNA markers. We explored the historical dimension of this genetic differentiation between northern and southern populations to evaluate phylogeographic structure.

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The impact of chronic hepatitis C (HCV) worldwide is expected to increase as the population infected with HCV ages and more undiagnosed individuals are identified and linked to care through nation-wide initiatives. The development of interferon-free regimens involving the use of direct-acting antiviral agents, which disrupt key steps in viral replication, has revolutionized the treatment of chronic HCV infection. However, there remains a great medical need for HCV therapy that is of shorter duration, all-oral, with a high barrier to resistance, and highly effective for all patient populations including those with end-stage renal disease (ESRD) and cirrhosis.

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Article Synopsis
  • Understanding the genetic differentiation and speciation processes in marine species like the Chilean dolphin is complicated due to their high dispersal abilities.
  • A study identified two distinct populations of Chilean dolphins in northern and southern coastal habitats through genetic analysis of skin samples collected over several years.
  • Although both populations have similar levels of genetic diversity, significant genetic differentiation suggests minimal gene flow between them, indicating they should be managed as separate conservation units due to their ecological adaptations.
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