Sang-Hyun Han

Length difference between equine ZFX and ZFY genes and its application for molecular sex determination

PurposeWe analyzed the sex chromosome-encoding ZFX-ZFY genes and tested molecular sexing using the amplification patterns of intron 9 of ZFX-ZFY in the horse.Methods and resultsThe amplification of the ZFX-ZFY produced two distinct patterns, reflecting sexual dimorphism based on a length difference between the X and Y chromosomes. The amplification products from foals showed two distinct bands: one was common to all foals and mares, indicating that this band was amplified from ZFX, while the other was specific to some foals, indicating that it was from ZFY. The result based on the PCR assay was identical to the results of amplification of the Y chromosome-specific SRY gene and those of investigations of the phenotypic gender in three different horse populations.ConclusionWe suggest that this PCR strategy for determining sexes by comparing the amplification patterns of ZFX-ZFY genes is a convenient and precise method for discriminating sexes in horses.

A promoter polymorphism of MSTN g.−371T>A and its associations with carcass traits in Korean cattle

A promoter polymorphism of bovine Myostatin (MSTN) gene g.−371T>A was screened in Holstein and two Korean indigenous cattle breeds, Hanwoo and Jeju Black cattle (JBC). The MSTN g.−371T>A polymorphism was found in all three cattle breeds tested. An allele MSTN g.−371A was the most frequent in the JBC breed among breeds tested. The association of MSTN genotypes for carcass traits was also tested in the Hanwoo population. Significant differences were found between the genotypes and level of meat quality grade index which converted the marbling score levels (Pxa0<xa00.05), reflecting the metabolic role of MSTN for inhibition of preadipocyte differentiation in intramuscular fat deposition. In addition, significant differences were found for fat color index of backfat according to MSTN genotypes (Pxa0<xa00.05), suggesting that MSTN may play a role in deposition of white-yellow adipocytes in backfat. However, there was no detection of significant association of genotypes with the live weight, carcass weight, backfat thickness, eye muscle area, marbling score, or meat color index (Pxa0>xa00.05). Despite the lack of statistical association, wild type g.−371T/-showed association patterns similar to those of A/A homozygotes, such as heavier weights, thinner backfat, larger eye muscle area, and lower marbling score. The results of the present study suggest that MSTN promoter polymorphism g.−371T>A may affect carcass traits, which could be a useful molecular marker for planning improvements in the economic traits of Korean cattle breeds.

Porcine SPP1 gene polymorphism association with phenotypic traits in the Landrace × Jeju (Korea) black pig F2 population

This study examined polymorphisms of the secreted phosphoprotein 1 (SPP1) gene and its association with growth and carcass traits in the F2 population of the crossbred Landracexa0×xa0Jeju (Korea) Black pig. The authors detected the presence/absence polymorphisms of short interspersed nuclear element in the SPP1 intron 6 of the population; they then designated the longer fragment as allele A and the shorter one as allele B. The SPP1A/B heterozygous pigs evidenced significantly heavier body weight at birth and on days 21 and 70, and a higher level of average daily gain during the early developmental period than was seen in the A/A and B/B homozygous pigs (Pxa0<xa00.05). Further, the SPP1A/B heterozygous pigs evidenced significantly greater body length, less backfat thickness measured at three different sites, and larger loin muscle area than the homozygotes (Pxa0<xa00.05). On the other hand, the levels of late average daily gain, 140th-day body weight, and marbling score were not significantly associated (Pxa0>xa00.05). The results of this study reveal faster growth rate and differences in pig productivity according to genotypes of the SPP1 gene. These findings demonstrate that SPP1 genotypes may effectively function as molecular genetic markers for the improvement of Jeju Black pig-related crossbreeding systems.

SINE indel polymorphism of AGL gene and association with growth and carcass traits in Landrace × Jeju black pig F2 population

Genetic polymorphisms in the glycogen debrancher enzyme (AGL) gene were assessed with regard to their association with growth and carcass traits in the F2 population crossbred Landrace and Jeju (Korea) Black pig. Three genotypes representing the insertion and/or deletion (indel) polymorphisms of short interspersed nuclear element were detected at frequencies of 0.278 (L/L), 0.479 (L/S), and 0.243 (S/S), respectively. The AGL S allele-containing pigs evidenced significantly heavier body weights at birth, the 3rd week, 10th week, and 20th week during developmental stages and higher average daily gains during the late period than were noted in the L/L homozygous pigs (Pxa0<xa00.05), respectively. However, average daily gains during the early period were not significantly associated with genotype distribution (Pxa0>xa00.05). With regard to the carcass traits, the S allele pigs (S/-) evidenced significantly heavier carcass weights and thicker backfat than was measured in L/L homozygous pigs (Pxa0<xa00.05). However, body lengths, meat color, and marbling scores were all found not to be statistically significant (Pxa0>xa00.05). Consequently, the faster growth rate during the late period and backfat deposition rather than intramuscular fat deposition cause differences in pig productivity according to genotypes of the AGL gene. These findings indicate that the AGL genotypes may prove to be useful genetic markers for the improvement of Jeju Black pig-related crossbreeding systems.

Identifying the species of origin in commercial sausages in South Korea

ABSTRACT This study aimed to develop a rapid and reliable method for identifying the species origin of the meat in commercial sausages using amplification patterns for mitochondrial DNA (mtDNA). Forty commercial sausages were purchased from retail markets and subjected to mtDNA analysis. Two mtDNA markers were used for amplifying the meat source DNA. To optimize the PCR conditions, gradient PCR reactions were carried out to determine the primer annealing temperatures, and real-time PCR was done to check the minimal amount of DNA solution and to examine the cross-reaction. PCR products were observed on the gels suggesting that DNA molecules may be useful in the identification of the meat source in processed sausages. A similarity search of the DNA sequences showed that they were from pig, chicken, and fish, as described on the product labels. The real-time PCR results showed that the PCR products were observed above 10 fg (0.01 pg)/μl concentrations in pig, chicken, and processed fish meat DNA. No significant amplification was found in cross-species. This PCR-based molecular method using mtDNA markers may provide useful information for food safety and traceability purposes by supplying molecular evidence for detecting and identifying the meat sources used in sausage production.

Induction of Primary Male in Juvenile Red Spotted Grouper Epinephelus akaara by Immersion of 17α-Methyltestosterone.

We investigated the androgenic effects of 17α- methyltestosterone (MT) on gonadal sex reversal in juvenile red spotted grouper Epinephelus akaara. The fish were immersed in 17α-MT at 1 and 5 mg/L. Treatment method of 17α-MT was once weekly for 4 and 8 weeks. Fish were sampled at 12 months after end of the treatment period in order to histological analysis. At the initiation of an experiment (70 day after hatching), juvenile red spotted grouper have the paired primordial gonads with somatic cells bellow kidney in the posterior portion of the body cavity. Formation of ovarian cavity indicates that the ovarian differentiation beginning at 70 DAH in red spotted grouper. At 12 months after end of the treatment period, control group, 17α-MT 1 mg/L treatment group for 4 and 8 weeks, and 17α-MT 5 mg/L treatment group for 4 weeks were all female. However, sex-changed males without ovarian cavity were observed in the 17α-MT 5 mg/L treatment group for 8 weeks. In grouper, we firstly reported that the red spotted grouper be able to induce the primary males by hormone treatment prior to gonadal sex differentiation.

Two cases of meningocele and meningoencephalocele in Jeju native pigs

BackgroundMeningocele and meningoencephalocele of the skull are congenital deformities. Various species, such as pigs, dogs, and cats, are susceptible to congenital meningocele and meningoencephalocele and the incidence is higher in large white and landrace pigs.Case presentationIn this study, swelling was observed in the fontanel areas of the median planes of the skull cap in two female piglets of the same litter. Gross clinical examination, neurological examination, computed tomography (CT), and magnetic resonance imaging (MRI) were conducted on the symptomatic piglets. The gross clinical and neurological examinations revealed no specific findings, except for the swellings. According to the CT results, the length of the defect on the sagittal section of the skull was 4.7xa0mm in case 1 and 20.62xa0mm in case 2. Connected flow between the skull swellings and the cerebrospinal fluid (CSF) of the lateral ventricles was observed, and partial herniation was identified in case 2. On MRI, CSF with high T2 signals was identified in the arachnoid spaces between the cerebrum and the cerebellum in the two cases, which is consistent with intracranial hypertension. The size of the swelling formed in the parietal bones was 1.6u2009×u20091.1u2009×u20091.8xa0cm3 (case 1) and 1.2u2009×u20091.38u2009×u20091.7xa0cm3 (case 2). The increase in intracranial pressure was more obvious in case 2 than in case 1, and was accompanied by posterior displacements of the mesencephalon and cerebellum.ConclusionsCase 1 was diagnosed as meningocele resulting from meningeal herniation and case 2 was diagnosed as meningoencephalocele caused by brain tissue herniation.

Effects of POU1F1 and GH1 genotypes on carcass traits in Hanwoo cattle

Growth hormone and pituitary specific transcription factor-1 are expressed in the pituitary gland and play critical roles in the development and growth of mammals. Genetic polymorphisms of GH1 and POU1F1 genes were investigated using PCR-RFLP and tested for statistical associations with meat quality traits in Hanwoo cattle. Three genotypes were found for each gene in a population of Hanwoo steers reared for beef production. No meat quality traits were significantly associated with the GH1 genotypes. Animals with the GH1 Leu/Leu genotype had heavier weights and higher marbling scores, but statistical significance was not detected. Backfat thickness was associated with POU1F1 genotypes. Backfat of POU1F1 G/G homozygotes was thicker than that of other genotypes (p < 0.05). Other carcass traits, including weight at slaughter, carcass weight, carcass yield ratio, eye muscle area, marbling score, meat color, and fat color were statistically insignificant in POU1F1 genotypes (p > 0.05). These findings suggest that the POU1F1 G/G genotype may contribute to improving body weights and backfat in Hanwoo steers using sire-based predictions.

Complete mitochondrial genome of the Ussuri white-toothed shrew Crocidura lasiura (Insectivora, Soricidae)

Abstract We obtained the complete mitochondrial genome of the Ussuri white-toothed shrew Crocidura lasiura (Insectivora, Soricidae) at 17u2009362 base pairs (bp) containing 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a non-coding control region. Its gene order is identical to that of other vertebrates. Several repeat elements were identified in the non-coding control region (D-loop). Phylogenetic tree using mt protein-coding gene sequences showed that C. lasiura was closely related to C. attenuata. The reports of mt genome sequences of Crocidura were not enough to study phylogenetic relationships in genome levels. However, this report may help us to understand the phylogenetic relationships and evolutionary history of Crocidura.

The complete mitochondrial genome and phylogenetic position of the Endangered red-spotted grouper Epinephelus akaara (Perciformes, Serranidae) collected in South Korea

Abstract We determined complete nucleotide sequences of the mitochondrial genome of two individuals of the Red-spotted grouper, Epinephelus akaara (Perciformes, Serranidae), caught in South Korea. The mitochondrial genome had 16,795 base pairs (bp) and 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a noncoding control region. The two mt genomes were highly homologous (99.71% similarity). The two mt genomes of E. akaara analyzed in this study were found in Clade I with those of E. awoara, E. fasciatomaculosus, E. sexfasciatus, E. diacanthus, E. sticus, and E. morio. Here, we reported the complete mt genome sequence of E. akaara, suggesting that this may use in phylogenetic studies of Epinephelus.