Modular chromosome rearrangements reveal parallel and nonparallel adaptation in a marine fish.

Genomic architecture and standing variation can play a key role in ecological adaptation and contribute to the predictability of evolution. In Atlantic cod (), four large chromosomal rearrangements have been associated with ecological gradients and migratory behavior in regional analyses. However, the degree of parallelism, the extent of independent inheritance, and functional distinctiveness of these rearrangements remain poorly understood.

A migration-associated supergene reveals loss of biocomplexity in Atlantic cod.

Chromosome structural variation may underpin ecologically important intraspecific diversity by reducing recombination within supergenes containing linked, coadapted alleles. Here, we confirm that an ancient chromosomal rearrangement is strongly associated with migratory phenotype and individual genetic structure in Atlantic cod () across the Northwest Atlantic. We reconstruct trends in effective population size over the last century and reveal declines in effective population size matching onset of industrialized harvest (after 1950).

Range-wide genomic data synthesis reveals transatlantic vicariance and secondary contact in Atlantic cod.

Recent advances in genetic and genomic analysis have greatly improved our understanding of spatial population structure in marine species. However, studies addressing phylogeographic patterns at oceanic spatial scales remain rare. In Atlantic cod (), existing range-wide examinations suggest significant transatlantic divergence, although the fine-scale contemporary distribution of populations and potential for secondary contact are largely unresolved.

Prothrombin G20210A mutation and sudden death.

The authors present a case of sudden death in a previously healthy 36-year-old male. At autopsy there were bilateral pulmonary thromboemboli and right ventricular dilatation. Histologic findings in the lungs included recanalized, old thrombi and evidence of pulmonary hypertension.