• Korean Journal of Ichthyology
• /
• v.24 no.1
• /
• pp.1-10
• /
• 2012

Reciprocal hybrids between the mud loach ($Misgurnus$ $mizolepis$) and cyprinid loach ($M.$ $anguillicaudatus$) were produced by artificial fertilization. The chromosome number of mud loach was 2n=48, consisting of 12M+4SM+32A chromosomes. The cyprinid loach has 2n=50, consisting of 10M+4SM+36A chromosomes. The chromosome numbers of the diploid reciprocal hybrids were 2n=49, consisting of 11M+4SM+34A chromosomes. All the karyotypes documented in this study had the same arm number of 64. There was no evidence of chromosomal polymorphisms or sex-related heteromorphism. The cytogenetic traits of the hybrid genotypes were intermediate between those of the parent species. In all genotypes, the chromosomal NORs localized to the terminal short arms of the same metacentric chromosome pair. These results suggest that Robertsonian translocation occurred between metacentric chromosome 1 of mud loach and acrocentric chromosome of cyprinid loach.

• Journal of Genetic Medicine
• /
• v.13 no.2
• /
• pp.95-98
• /
• 2016

We report the prenatal diagnosis of an unbalanced translocation between chromosome Y and chromosome 15 in a female fetus. Cytogenetic analysis of parental chromosomes revealed that the mother had a normal 46,XX karyotype, whereas the father exhibited a 46,XY,der(15)t(Y;15) karyotype. We performed cytogenetic analysis of the father's family as a result of the father and confirmed the same karyotype in his mother and brother. Fluorescence in situ hybridization and quantitative fluorescent-polymerase chain reaction analysis identified the breakpoint and demonstrated the absence of the SRY gene in female members. Thus, the proband inherited this translocation from the father and grandmother. This makes the prediction of the fetal phenotype possible through assessing the grandmother. Therefore, we suggest that conventional cytogenetic and molecular cytogenetic methods, in combination with family history, provide informative results for prenatal diagnosis and prenatal genetic counseling.

• Journal of Aquaculture
• /
• v.3 no.1
• /
• pp.31-37
• /
• 1990

Ten strains of tilapiine species from genus Oreochromis were cytogenetically studied for genetic stock identification. Both the chromosome numbers(2n=44) were identical in all 10 strains. Heteromorphic sex chromosome pair were not found in any strains. Nuclear volumes vary between O. niloticus(21.0 $\mu$ $m^3$) and O. aureus(22.4 $\mu$ $m^3$)

• Korean Journal of Veterinary Research
• /
• v.44 no.2
• /
• pp.159-162
• /
• 2004

We investigated the cytogenetic characteristics of male black-striped field mouse (Apodemus agrarium) in Korea. Chromosome slides were obtained from blood cell cultures which were synchronized with thymidine blocking or not. In the chromosome slide which synchronization with thymidine blocking was employed on, the GTG(G bands by trypsin using Giemsa)-bands of high resolution were observed. The male black-striped field mouse has 48 chromosomes composed 46 autosomes and XY sex chromosomes. The centromeric regions of autosomes were positive to GTG-banding. According to this investigation, thymidine blocking in cell culture process was useful to get lengthened chromosomes. It may be necessary to employ RBG-banding technique to investigate complementary band patterns between R- and G-banding in black-striped field mouse.

• The Korean Journal of Zoology
• /
• v.16 no.3
• /
• pp.171-176
• /
• 1973

Metaphases were obtained from the bone marrow cells of B. kangii Yoon, by means of direct air-drying technique. The karylogical characteristics of this species were as follows; 1) The diploid chromosome number was 22(2n=22) which might be divided into six large and five small homololgous chromosmes. 2) All homologous chromosomes of this species were metacentrics. 3) The secondary constriction was not found in all members of chromosomes. 4) There was no evidence for the existence of a specific sex chromosome pair in this species.

• Journal of Life Science
• /
• v.15 no.1 s.68
• /
• pp.45-48
• /
• 2005

The aim of this study was to construct a correct pedigree of miniature horses (MH). The sex of MH was detected by PCR amplification of the sex determining region of the Y chromosome gene (SRY) prior to parentage testing. Ten random MH samples for parentage testing were genotyped by using 16 micro satellite markers. Since the SRY band (430 bp) was detected in horses No.1, 2, 6, 7, 8, 9, 10, these are male. However, the DNA segment was not identified in horses No.3, 4, and 5, which therefore are female. After genotyping, parentage testing was performed according to Mendelian fashion and International Society for Animal Genetics (ISAG) guideline. Of the 10 MH, 3 were qualified by the compatibility of 16 markers according to Mendelian fashion in the present DNA typing for parentage verification. These results can provide basic information for developing parentage verification and an individual identification system in MH.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.10
• /
• pp.1411-1416
• /
• 2014

Gender selection is important in livestock industries; for example, female calves are required in the dairy industry. Sex-sorted semen is commonly used for the production of calves of the desired gender. However, assessment of the sex ratio of the sorted semen is tedious and expensive. In this study, a rapid, cost effective and reliable method for determining the sex ratio was developed using a multiplex real-time polymerase chain reaction (PCR) assay. In this assay, the X and Y chromosome-specific markers, i.e., bovine proteolipid protein (PLP) gene and sex-determining region Y (SRY) were simultaneously quantified in a single tube. The multiplex real-time PCR assay was shown to have high amplification efficiencies (97% to 99%) comparable to the separated-tube simplex real-time PCR assay. The results obtained from both assays were not significantly different (p>0.05). The multiplex assay was validated using reference DNA of known X ratio (10%, 50%, and 90%) as templates. The measured %X in semen samples were the same within 95% confidence intervals as the expected values, i.e., >90% in X-sorted semen, <10% in Y-sorted semen and close to 50% in the unsorted semen. The multiplex real-time PCR assay as shown in this study can thus be used to assess purity of sex-sorted semen.

• Korean Journal of Poultry Science
• /
• v.13 no.2
• /
• pp.167-172
• /
• 1986

Chromosome size, number and shape were studied by the centromeric index, the arm ratio and the relative length of chromosome. The chromosomes of 50 early chick embryos which were derived from a pure line of Single Comb White Leghorns were examined. Using a colchicine, hypotonic treatment, fixation and air-drying technique, the clear prometaphase figures were obtained from the whole embryo. The results of the present investigation of chromosome pairs were as follows, 1. Pair 1 and 2; metacentric and submetacentric chromosomes which could be clearly distinguished from each other by size. 2. Pair 3 and 4: acrocentric chromosomes of similar length but the 4th pair had a distinct short arm which was not present in the 3rd. 3, Pair 5; metacentric sex chromosomes, 2 chromosome had relative 5th length but the W chromosome had slightly shorter length than 7th pair of chromosomes. 4. Pair 6; acrocentric chromosomes similar in shape to pair 3 but of little more than half the size. 5, Pair 7 and 8; acrocentric chrocentric but the 7th pairs had a definite short arm. 6. Pair 9; similar length to the 7, 8 pairs but had a medially placed centromere. 7. microchromosomes of 30 pairs ; nearly all acrocentric chromosomes which appeared as paired dots. The total number of diploid was appeared to 72-78. But a number of observations presented the total diploid number in 78 (58%). The inconstancy in number observed in this study was presumably due to the minute size of the microchromosomes. Thus, the modal numbers for the diploid chromosome was at least 78.

• Journal of Life Science
• /
• v.27 no.4
• /
• pp.464-470
• /
• 2017

Three Korean native cattle (KNC) and seven exotic breeds (Chikso, Hanwoo, Jeju black, Holstein, Japanese black, Charolais, Angus, Hereford, Simmental, and Cross breed) were characterized by using five microsatellite (MS) markers (INRA30, TGLA325, UMN0803, UMN0905, and UMN0929) from the sex chromosome. Genetic diversity was evaluated across the 10 breeds by using the number of alleles per locus, allele frequency, heterozygosity, and polymorphism information content (PIC) to search for locus and/or breed specific alleles, allowing a rapid and cost-effective identification of cattle samples, avoiding mislabeling of commercial beef. It was divided into two main groups from STRUCTURE analysis, one corresponding to KNC and the other to exotic cattle breeds. These results also showed specific genetic differences between KNC and exotic breeds. Nei's standard genetic distance was calculated and used in the construction of a neighbor-joining tree. Results evidenced a correspondence between genetic distance, breeds' history, and their geographic origin, and a clear separation between KNC and exotic breeds. Overall, this study evidenced that DNA markers can discriminate between domestic and imported beef, contributing to the knowledge on cattle breeds' genetic diversity and relationships by using MS markers of the sex chromosome. These markers would be useful for inhibitory effect about false sales and for building an effective tracking system.

• Journal of Genetic Medicine
• /
• v.9 no.1
• /
• pp.17-21
• /
• 2012

Purpose: The aim of this study was to analyze parental decisions regarding pregnancies in which the fetus had sex chromosome abnormalities (SCA) over a ten-year period. Materials and Methods: We collected and reviewed records from our hospital for 2001-2010 and a genetic specialist provided-genetic counseling. Results: We diagnosed 130 cases (0.71%) with SCA out of 18,376 prenatal cases from 2001 to 2010. We reviewed the records and the results of all pregnancies. We also included cases (n=84) of apparently normal anatomic fetuses to analyze the factors influencing parental decisions. We excluded 34 cases with an obvious anomaly or a presumably bad outcome and 12 cases that were not followed up. Forty-three couples (51.2%) continued their pregnancies while forty-one (48.8%) terminated them. Of 38 mosaicism cases, 21 (55.3%) were continued. Among the 20 pregnancies assisted by reproductive techniques, 15 (75%) were continued (P=0.02). More pregnancies were continued when genetic counseling was provided (61.9%) compared to cases in which it was not provided (19%) (P=0.01). Conclusion: Genetic counseling is important in providing appropriate information to parents. Establishing guidelines and protocols will help both obstetricians and parents to make informed decisions.