Marker-assisted breeding for viral disease resistance in Japanese flounder (Paralichthys olivaceus)

DNA marker technologies can be used for genetic improvement through selection of favorable traits such as disease resistance. These traits are generally modeled as being controlled by many genes of small additive effects, known as quantitative trait loci (QTL). Construction of a genetic linkage map based on DNA markers at a large number of sites in the fish genome is necessary to identify QTL controlling traits of disease resistance. By identifying markers associated with high per- formance QTL in different strains or species, it may be possible to improve the performance of such traits in other strains through intro- gression of the desired QTL. One of the goals of selective breeding programs is to integrate genetic marker information from pedigreed brood stock into successful management and culture. Such an approach, termed marker- assisted selection (MAS) and/or marker- assisted gene introgression (MAI), is expect- ed to increase genetic response by affecting efficiency and accuracy of selection

Status Epilepticus as the Initial Presentation of Intravascular Lymphoma

Intravascular lymphoma (IVL) is a rare disease form of malignant lymphoma, and it is characterised by the selective growth of lymphoma cells within the lumina of vessels. Identification of this disease at an early stage is difficult because of non-specific clinical symptoms and neuroradiological findings. Most reported IVL cases are diagnosed at post-mortem following autopsy. We report the case of a patient who presented with status epilepticus (SE) as the initial manifestation of IVL. Despite the administration of anti-convulsant agents and general care the patient’s condition deteriorated rapidly after admission, culminating in death due to respiratory failure and heart failure 21 days after the onset of symptoms. Post-mortem examination revealed IVL in the brain and multiple organs. Epileptic seizures often appear during the clinical course of IVL; however, they occur most frequently at advanced stages. Diagnosis of IVL that first presents with SE is of clinical importance because the treatment and prognosis of acute SE arising from IVL are different from those of SE originating from other causes

Genetic parameters and quantitative trait loci analysis associated with body size and timing at metamorphosis into glass eels in captive-bred Japanese eels (Anguilla japonica).

The Japanese eel (Anguilla japonica) is among the most important aquaculture fish species in Eastern Asia. The present study aimed to identify the genetic parameters underlying body size and the timing at metamorphosis from leptocephali to glass eels in captive-bred Japanese eels, with the intent to foster sustainable development. Larvae from a partly factorial cross (14 sires × 11 dams) were reared until the point of metamorphosis into glass eels. In these organisms, we observed moderate heritability and mild genetic correlations among traits related to body size (h2 = 0.16-0.33) and timing at metamorphosis (h2 = 0.36-0.41). In an F1 full-sib family, quantitative trait loci (QTL) mapping for these traits identified one significant (genome-wide P < 0.05) and five suggestive QTLs (chromosome-wide P < 0.05). These results suggest that in the Japanese eel, metamorphic traits exhibit a polygenic genetic structure comprising many QTLs with small effects. In addition, we updated the genetic linkage map for the Japanese eel and integrated it with our newly constructed de novo genome assembly. The information and tools generated from this study will contribute to the development of freshwater eel genetics and genomics

Whole Genome Sequencing of Greater Amberjack (Seriola dumerili) for SNP Identification on Aligned Scaffolds and Genome Structural Variation Analysis Using Parallel Resequencing

Greater amberjack (Seriola dumerili) is distributed in tropical and temperate waters worldwide and is an important aquaculture fish. We carried out de novo sequencing of the greater amberjack genome to construct a reference genome sequence to identify single nucleotide polymorphisms (SNPs) for breeding amberjack by marker-assisted or gene-assisted selection as well as to identify functional genes for biological traits. We obtained 200 times coverage and constructed a high-quality genome assembly using next generation sequencing technology. The assembled sequences were aligned onto a yellowtail (Seriola quinqueradiata) radiation hybrid (RH) physical map by sequence homology. A total of 215 of the longest amberjack sequences, with a total length of 622.8 Mbp (92% of the total length of the genome scaffolds), were lined up on the yellowtail RH map. We resequenced the whole genomes of 20 greater amberjacks and mapped the resulting sequences onto the reference genome sequence. About 186,000 nonredundant SNPs were successfully ordered on the reference genome. Further, we found differences in the genome structural variations between two greater amberjack populations using BreakDancer. We also analyzed the greater amberjack transcriptome and mapped the annotated sequences onto the reference genome sequence