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A phylogeographic study of the circumtropical glasseye Heteropriacanthus cruentatus was conducted. Molecular analyses indicate two mitochondrial cytochrome c oxidase subunit I ( coI) lineages that are 10·4% divergent: one in the western Atlantic (Caribbean) and another that was detected across the Indo-Pacific. A fixed single nucleotide polymorphism ( SNP) was detected at a nuclear locus (S7 ribosomal protein) and is consistent with this finding. There is evidence of recent dispersal from the Atlantic to the Indian Ocean with individuals of mixed lineages detected in South Africa and the Mozambique Channel. Using coalescent analyses of the mitochondrial dataset, time of divergence between lineages was estimated to be c. 15·3 million years. The deep divergence between these two lineages indicates distinct evolutionary units, however, due to the lack of morphological differences and evidence of hybridization between lineages, taxonomic revision is not suggested at this time. [ABSTRACT FROM AUTHOR]

Twelve polymorphic microsatellite loci were developed for the Yellow-Striped Goatfish Mulloidichthys flavolineatus, from shallow shotgun pyrosequencing of genomic DNA. The 12 loci were characterized in a sample of 47 individuals from the Big Island of Hawai'i, 21 individuals from Johnston Atoll (North Pacific) and 24 individuals from Okinawa (West Pacific). We found a mean of 8.08 ± 2.43 SEM alleles per locus (range 5-12 alleles) and observed levels of heterozygosity ranging from 0.15 to 0.87. Although three loci deviated significantly from HWE expectations (locus mflssr004: Big Island, P = 0.038; locus mflssr026: Johnston, P = 0.034; locus mflssr034: Big Island, P < 0.001, Okinawa, P = 0.023), none of the loci deviated from HWE consistently across all locations. The twelve new markers reported here constitute the first set of microsatellite loci reported for any member of the goatfish family (Mullidae) and will be used to study historical biogeography and contemporary migration, as well as to inform patters of connectivity for conservation purposes. [ABSTRACT FROM AUTHOR]

Abstract Background There are few genomic tools available in melon (Cucumis melo L.), a member of the Cucurbitaceae, despite its importance as a crop. Among these tools, genetic maps have been constructed mainly using marker types such as simple sequence repeats (SSR), restriction fragment length polymorphisms (RFLP) and amplified fragment length polymorphisms (AFLP) in different mapping populations. There is a growing need for saturating the genetic map with single nucleotide polymorphisms (SNP), more amenable for high throughput analysis, especially if these markers are located in gene coding regions, to provide functional markers. Expressed sequence tags (ESTs) from melon are available in public databases, and resequencing ESTs or validating SNPs detected in silico are excellent ways to discover SNPs. Results EST-based SNPs were discovered after resequencing ESTs between the parental lines of the PI 161375 (SC) × 'Piel de sapo' (PS) genetic map or using in silico SNP information from EST databases. In total 200 EST-based SNPs were mapped in the melon genetic map using a bin-mapping strategy, increasing the map density to 2.35 cM/marker. A subset of 45 SNPs was used to study variation in a panel of 48 melon accessions covering a wide range of the genetic diversity of the species. SNP analysis correctly reflected the genetic relationships compared with other marker systems, being able to distinguish all the accessions and cultivars. Conclusion This is the first example of a genetic map in a cucurbit species that includes a major set of SNP markers discovered using ESTs. The PI 161375 × 'Piel de sapo' melon genetic map has around 700 markers, of which more than 500 are gene-based markers (SNP, RFLP and SSR). This genetic map will be a central tool for the construction of the melon physical map, the step prior to sequencing the complete genome. Using the set of SNP markers, it was possible to define the genetic relationships within a collection of forty-eight melon accessions as efficiently as with SSR markers, and these markers may also be useful for cultivar identification in Occidental melon varieties.