The fate of recent duplicated genes following a fourth-round whole genome duplication in a tetraploid fish, common carp (Cyprinus carpio).

Whole genome duplication (WGD) results in extensive genetic redundancy. In plants and yeast, WGD is followed by rapid gene deletions and intense expression differentiation with slow functional divergence. However, the early evolution of the gene differentiation processes is poorly understood in vertebrates because almost all studied WGDs are extremely ancient, and the genomes have returned to a diploid status. Common carp had a very recent fourth round of WGD dated to 8 million years ago. It therefore constitutes an ideal model to study early-stage functional divergence and expression differentiation in vertebrates. We identified 1,757 pairs of recently duplicated genes (RDGs) originating from this specific WGD and found that most ancestral genes were retained in duplicate. Most RDGs were conserved and under selective pressure. Gene expression analysis across six tissues revealed that 92.5% of RDG pairs were co-expressed in at least one tissue and that the expression of nearly half pairs ceased to be strongly correlated, indicating slow spatial divergence but rapid expression dissociation. Functional comparison revealed that 25% of pairs had functional divergence, of which neo- and sub-functionalization were the main outcomes. Our analysis revealed slow gene loss but rapid and intense expression and function differentiation after WGD.

[Genomic selection and its application].

Selective breeding is very important in agricultural production and breeding value estimation is the core of selective breeding. With the development of genetic markers, especially high throughput genotyping technology, it becomes available to estimate breeding value at genome level, i.e. genomic selection (GS). In this review, the methods of GS was categorized into two groups: one is to predict genomic estimated breeding value (GEBV) based on the allele effect, such as least squares, random regression - best linear unbiased prediction (RR-BLUP), Bayes and principle component analysis, etc; the other is to predict GEBV with genetic relationship matrix, which constructs genetic relationship matrix via high throughput genetic markers and then predicts GEBV through linear mixed model, i.e. GBLUP. The basic principles of these methods were also introduced according to the above two classifications. Factors affecting GS accuracy include markers of type and density, length of haplotype, the size of reference population, the extent between marker-QTL and so on. Among the methods of GS, Bayes and GBLUP are usually more accurate than the others and least squares is the worst. GBLUP is time-efficient and can combine pedigree with genotypic information, hence it is superior to other methods. Although progress was made in GS, there are still some challenges, for examples, united breeding, long-term genetic gain with GS, and disentangling markers with and without contribution to the traits. GS has been applied in animal and plant breeding practice and also has the potential to predict genetic predisposition in humans and study evolutionary dynamics. GS, which is more precise than the traditional method, is a breakthrough at measuring genetic relationship. Therefore, GS will be a revolutionary event in the history of animal and plant breeding.

Rates and patterns of microsatellite mutations in common carp (Cyprinus carpio L.).

During genotyping 150 microsatellites in a F1 family of common carp, six mutations were found at five microsatellite loci. The overall mutation rate of common carp microsatellites was 2.53 X 10(-4) per locus per generation. At five loci, mutations increased the length of alleles by at least one repeat unit, suggesting mutations at microsatellite loci in common carp do not follow strict stepwise mutation model. The data on mutation rates and patterns can facilitate population genetics studies, and provide useful parameters for estimating a long-term effective population size of common carp.

Association analysis of thyroglobulin gene variants with carcass and meat quality traits in beef cattle.

Thyroid hormones play an important role in regulating the metabolism and can affect the homeostasis of fat deposition. The gene encoding thyroglobulin (TG), producing the precursor for thyroid hormones, has been proposed as a positional and functional candidate gene for a QTL with an effect on fat deposition. In the present study, we identified 6 novel SNPs at the 3' flanking region of the TG gene. The SNP marker association analysis indicated that the SNP markers G133C, G156A, C220T and A506C were significantly associated with marbling score (P<0.05, N=271). Animals with the new homozygote genotype had higher marbling scores than those with the other genotypes. Besides, the linkage disequilibrium analysis indicated that these 4 SNPs were completely linked (r2 = 1). Results of this study suggest that the TG-gene-specific SNP may be a useful marker for meat quality traits in future marker-assisted selection programmes in beef cattle.

Mesostructured tin oxide as sensitive material for C(2)H(5)OH sensor.

Mesostructured tin oxide with high specific surface area was synthesized using cationic surfactant (cetyltrimethylammonium bromide, CTAB: CH(3)(CH(2))(15)N(+)(CH(3))(3)Br(-)) as the organic template and hydrous tin chloride (SnCl(4).5H(2)O) and NH(4)OH as the inorganic precursors under acidic conditions at ambient temperature. Thermogravimetric analysis (TGA), Fourier transformed infrared (FTIR), X-ray diffraction analysis (XRD), X-ray photoelectron spectrum (XPS) and N(2)-sorption isotherms were used to characterize the mesostructured tin oxide that was formed at room temperature as well as calcined at different temperature. The surface area of mesostructured tin oxide calcined at 400 degrees C is 136 m(2) g(-1). The indirect heating sensor using this material as sensitive body was fabricated on an alumna tube with Au electrodes and platinum wires. Electrical and sensing properties of such a sensor were investigated. It was found that the mesostructured tin oxide with high surface area had higher sensitivity to C(2)H(5)OH and selectivity to gasoline than commercial sample of polycrystalline tin(IV) oxide.