• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.310-317
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• 1995

The evolutionary relationships for 43 species in the taxa of the basidiomycetous yeast and related yeast-like fungi have been studied from the 43 18S rRNA partial sequences. Fibulobasidium inconspicuum showed a relatively close relationship to Filobasidiella neoformans. It is obvious that Tremella foliacea and Ustilogo rabenhorstiana form a independently different cluster from basidiomycetous yeast and seem to be phylogenetically distant from basidiomycetous yeast and each other. The basidiomycetous yeasts are believed more closely associated with Tremella foliacea than with Ustilago rabenhorstiana. The phenotypic criteria such as carotenoid pigments, teliospores, ballistospores seems not to be phylogenetically useful indicators.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.163-168
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• 2006

Improvement of crop yield can be achieved through understanding genetic variation in reproductive characters and its impact on yield components. The present study was performed to evaluate genetic diversity for reproductive growth characters in exotic germplasm resources and to determine the relationships between developmental and growth periods with yield and yield components in soybean cultivar groups. For phenotypic evaluation such as reproductive and agronomic traits, a total of 80 indigenous and exotic soybean cultivars collected from four different geographical regions (China, Japan, Korea, and Vietnam) were grown from May to November of 2003 at the Seoul National University Farm, Suwon, Korea ($127^{\circ}02'E$ longitude, $37^{\circ}26'N$ latitude). Most of all the characters exhibited wide range of phenotypic variation, of which pod number, seed number, and plant yield showed greater range as compared to other characters. Korean cultivar groups showed greater diversity than the other cultivar groups in seven characters. Correlation analysis showed that days to flowering (DTF) and days to maturity (DTM) had close association with agronomic traits as well as yield and yield components. Both DTF and DTM had positive correlation with the other characters except one hundred seed weight. Stepwise multiple linear regression revealed that seed and pod number were identified as being significant for plant yield. The results in this study indicated wide variation in agronomic traits including DTF and DTM, suggesting the valuable genetic resources in a soybean breeding program.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.9
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• pp.1232-1236
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• 2002

Direct and service sire genetic parameters for total number of pigs born (TNB), number of pigs born alive (NBA), total pig weight at birth (TWB), and average pig birth weight (ABW) were estimated by DF-REML under a multiple trait animal model. Data on 3,078 litters of the Yorkshire from Jan, 1975 to Dec, 1998 at National Livestock Research Institute were obtained. The animal model included fixed contemporary group effects and random additive direct, service sire, and residual effects. Additive genetic relationships among animals were included. A separate relationship matrix for service sires and their sire was also included. Additive direct heritability estimates for TNB, NBA, TWB, and ABW were 0.19, 0.18, 0.25 and 0.39, respectively. Service sire heritability estimates for TNB, NBA, TWB, and ABW were 0.02, 0.01, 0.02 and 0.01, respectively. The genetic and phenotypic correlations of TNB with NBA estimated in this study were 0.81 and 0.81, respectively, and the genetic and phenotypic correlations of TNB with TWB estimated were 0.82 and 0.76, respectively. Results indicate that service sires account for 1 to 2% of the total variation for TNB, NBA, TWB, and ABW. Further investigation is needed to determine whether the service sire effect is primarily genetic or environmental.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1516-1519
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• 2001

The data consisted of 369 lactation records for calvings over a sixteen-year period (1972-1987) and included only cows that had normal milk records. The data were analysed using a linear model containing the fixed effects of parity, year of calving and season of calving. The least squares means${\pm}$S.E. were $1,273{\pm}58.4kg$ for milk yield, and for post-partum body weight (kg) at 2, 3 and 4 months after calving were $343.40{\pm}3.96$, $346.10{\pm}4.10$ and $352.54{\pm}4.26$, respectively. With the exception of season of calving, the effects of parity and year of calving were significant (p<0.01) on the performance of the animals. Thus, the mean-milk yields 1162, 1351 and 1350, were similar for pre-, peak- and post rainy seasons, respectively. On the other hand, as parity increased from 1 to 3, milk yield also increased, but thereafter, there was a gradual decline in milk yield. Similarly, post-partum body weight also increased with parity. However, no consistent pattern for year effect was observed which probably was a reflection of the variation in climatic conditions, or forage quality and/or availability. The phenotypic correlations between milk yield and post-partum body weights were negative and small (ranging from -0.01 to -0.08). However, high milk production in cows was associated with longer calving interval. The implications from the phenotypic correlations are suggestive of one or two possibilities. Firstly, selection for increased body weight may actually result in decreased milk yield. Also, a substantial genetic antagonism may exist between milk yield and fertility in the crossbred cows. Therefore, it is important that selection to improve milk production should take into consideration the reproductive performance of the cows.

• Journal of Microbiology
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• v.45 no.5
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• pp.466-472
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• 2007

A total of 98 vancomycin-resistant Enterococcus faecium (VREF) isolates (58 isolates from patients and 40 isolates from poultry) were compared based on their antimicrobial susceptibility, Tn1546 element organization, and pulsed-field gel electrophoresis (PFGE) patterns. This comparison aided in determining the relationships between the groups of isolates. All the VREF isolates harbored the vanA gene; however, 29 (29.6%) of the isolates exhibited the VanB phenotype-vanA genotype. Furthermore, the VREF isolates from humans and poultry exhibited distinct antimicrobial resistance patterns. The PCR mapping of the Tn1546 elements exhibited 12 different transposon types (A to L). The VREF isolates of poultry were classified into types A to D, whereas the human isolates were classified into types E to L. A PFGE analysis demonstrated a high degree of clonal heterogeneity in both groups of isolates; however, the distinct VREF clones appeared in each group of isolates. The deletion of the vanX-vanY genes or insertion of IS1216V in the intergenic region from the vanX-vanY genes is directly associated with the incongruence of the VanB phenotype-vanA genotype in human VREF isolates. These data suggest that the VREF isolates exhibit distinct phenotypic and genotypic traits according to their origins, which suggests that no evidence exists to substantiate the clonal spread or transfer of vancomycin resistance determinants between humans and poultry.

• Korean Journal of Agricultural Science
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• v.41 no.3
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• pp.229-236
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• 2014

This study presents the estimates of heritabilities of body measurement traits and carcass traits, and genetic and phenotypic correlations of those traits for crossbred pigs in Korea. Body and ultrasound (A mode: Piglog 105) measurements in 221 pigs including body weight, length, height and width, three back fat thickness at the points of 4th, 14th rib and chine bone, eye muscle area and lean meat percent were collected at the ages of 70, 145 and 180 days and then slaughtered to measure carcass weight, back fat, belly, collar butt, spare rib, picnic shoulder, hind leg, loin, tenderloin, lean meat yield and intramuscular rough fat content in loin. Genetic analysis was done using a multi-trait animal model. Heritabilties of the body measurements were ranged from 0.331 to 0.559 and three measurements of back fat thickness were also high as range varying from 0.402 to 0.475 for the ages of 145 and 180 days. However, eye muscle area was moderate (0.296) at the age of 180 days. Heritabilities of retail cut yields were also high as ranged from 0.387 to 0.474 and of IMF content in loin was 0.499. Heritabilities of the cut percent traits were ranged from 0.249 to 0.488. Important positive genetic and phenotypic correlations were noted for all carcass yield traits (0.298 to 0.875 and 0.432 to 0.922, respectively). IMF showed low negative genetic correlations with carcass yield traits, such as carcass weight, picnic shoulder, hind leg, loin, tenderloin and lean meat yield whereas low positive genetic correlations with back fat, belly, collar butt and spare rib. Loin, tenderloin and lean meat percent showed negative genetic correlations with carcass weight, back fat thickness, collar butt, spare rib and picnic shoulder percent. The four body measurements at the ages of 70, 145 and 180 days had positive genetic correlations with belly, shoulder butt, spare rib, picnic shoulder and hind leg percent, but negative genetic correlations were shown with loin and tenderloin percent except body measurements at 70 days. The results suggest that carcass yield are negatively correlated with intramuscular fat content, which is a major factor deciding pork quality and the yield of loin and tenderloin are not increased as much as increase in body size. However, the proportions of belly and collar butt are increased with the body size. In conclusion, selection strategy should be designed according to the preference on composition of carcass in each country.

• Journal of Life Science
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• v.20 no.11
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• pp.1697-1703
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• 2010

Asarum consists of low-growing herbs and is a genus in the Aristolochiaceae family with species found in the north temperate zones with most species in Asia. We evaluated the nine taxa with the trnL - trnT region of the chloroplast genome to estimate phenotypic relationships within genus Asarum in Korea. Alignment of the DNA sequences required the addition of numerous gaps. Sequence variation within the Asarum was mostly due to nucleotide inserts/deletions, although several indels and inserts were found. Another source of sequence divergence was length variation due to stretches of short repeats that occur at the trnL - trnT region in all the Asarum. A + T content for nine Korean species of genus Asarum ranged between 74.7% and 78.3%. These values were higher than those for the angiosperm alignments of the total trnL and trnT region (64.5~67.1%). Within genus Asarum, A. patens was strikingly different from the others in the three phylogenetic analyses (MP, ML, and NJ). However, some internal nodes were poorly supported. Within Korean Asarum, four species were unsolved portions. Possible reasons for the striking non-congruence between the previous morphological traits and the trnL - trnT based on phylogeny were discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1074-1080
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• 2017

Objective: The growth, carcass and retail cut yield records on 1,428 Hanwoo steers obtained through progeny testing were analyzed in this study, and their heritability and genetic relationships among the traits were estimated using animal models. Methods: Two different models were compared in this study. Each model was fitted for different fixed class effects, date of slaughter for carcass traits and batch of progeny test live measurement traits, and a choice of covariates (carcass weight in Model 1 or backfat thickness in Model 2) for carcass traits. Results: The differences in body composition among individuals were deemed being unaffected by their age at slaughter, except for carcass weight and backfat thickness. Heritability estimates of body size measurements were 0.21 to 0.36. Heritability estimates of retail cut percentage were high (0.56 from Model 1 and 0.47 from Model 2). And the heritability estimates for loin muscle percentage were 0.36 from Model 1 and 0.42 from Model 2, which were high enough to consider direct selection on carcass cutability traits as effective. The genetic correlations between body size measurements and retail cut ratio (RCR) were close to zero. But, some negative genetic correlations were found with chest girths measured at yearling (Model 1) or at 24 months of age or with chest widths. Loin muscle ratio (LMR) was genetically negatively correlated with body weights or body size measurements, in general in Model 1. These relationships were low close to zero but positive in Model 2. Phenotypic correlation between cutability traits (RCR, LMR) and live body size measurements were moderate and negative in Model 1 while those in Model 2 were all close to zero. Conclusion: Therefore, the body weights or linear body measurements at an earlier age may not be the most desirable selection traits for exploitation of correlated responses to improve loin muscle or lean meat yield.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.5
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• pp.712-721
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• 2020

Objective: The Wannan Black pig is a typical Chinese indigenous, disease-resistant pig breed with high fertility, and a crude-feed tolerance that has been bred by artificial selection in the south of Anhui province for a long time. However, genome variation, genetic relationships with other pig breeds, and domestication, remain poorly understood. Here, we focus on elucidating the genetic characteristics of the Wannan Black pig and identifying selection signatures during domestication and breeding. Methods: We identified the whole-genome variation in the Wannan Black pig and performed population admixture analyses to determine genetic relationships with other domesticated pig breeds and wild boars. Then, we identified the selection signatures between the Wannan Black pig and Asian wild boars in 100-kb windows sliding in 10 kb steps by using two approaches: the fixation index (F_ST) and π ratios. Results: Resequencing the Wannan Black pig genome yielded 501.52 G of raw data. After calling single-nucleotide variants (SNVs) and insertions/deletions (InDels), we identified 21,316,754 SNVs and 5,067,206 InDels (2,898,582 inserts and 2,168,624 deletions). Additionally, we found genes associated with growth, immunity, and digestive functions. Conclusion: Our findings help in explaining the unique genetic and phenotypic characteristics of Wannan Black pigs, which in turn can be informative for future breeding programs of Wannan Black pigs.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.193-199
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• 2002

The arylamine N-acetyltransferases (NATs) are a family of enzymes that N-acetylate mylhydrazines and arylamines through transfer of an acetyl group from acetyl coenzyme A. This activity was found to vary among individuals as a Mendalian trait and the basis of the genetic differences in human NAT activity is one of the best of the genetic studied examples of pharmacogenetic variation. The classical N-acetylation polymorphism is regulated at the NAT2 locus, which segregates individuals into rapid, intermediate, and slow acetylator phenotypes. In this study, the relationship between NAT2 activity phenotype using HPLC:UV assay for the determination of dapsone and monoacetyldapsone in plasma and NAT2 genotype by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) was investigated in the F2 hybrid (Fischer 344 vs Wistar-Kyoto) rats. Three Common mutant alleles at the NAT2 gene locus have been identified in the F2 generation progeny of Fischer 344 rats as raid acetylator and Wistar-Kyoto rats as slow acetylator segregated into three modes (low, intermediates, and high) with simple Mendelian inheritance. The metabolic activity of NAT2 of the intermediate and rapid acetylators is significant1y greater than slow acetylator, but the metabolic activity of rapid acetylator is not significantly different from Intermediate type. Therefore, we could observe that complete trimodal NAT2 genotypic alleles and incomplete trimodal NAT2 metabolic phenotypic distribution in tile F2 hybrid rats. These observations suggest that the relationships between NAT2 genotype and metabolic phenotype exists and F2 hybrid (Fischer 344: Wistar-Kyoto) animal models about NAT2 polymorphism might be applied in the toxicity and pharmacogenetic studies of arylamine drugs and carcinogens.