• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.15-21
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• 1999

The aim of the present study was to determine the effect of paternal sex chromosome on early development of buffalo embryos fertilized and cultured in vitro. Embryos were produced in vitro from abattoir derived buffalo oocytes. The cleaved embryos were cocultured with buffalo oviductal epithelial cells and evaluated on day 7 under the phase contrast microscope to classify development. The embryos which reached the morula/blastocyst stage were fast developing, the embryos which were at 16-32 cell stage were medium developing and the embryos below 16 cell stage were slow developing. The embryos which showed some fragmentation in the blastomeres or degenerated blastomeres, were degenerating. Sex of emberyos (n=159) was determined using PCR for amplification of a male specific BRY. 1 (301 bp) and a buffalo specific satellite DNA (216 bp) fragments. The results thus obtained show that 1) X and Y chromosome bearing sperms fertilize oocytes to give almost equal numbers of cleaved XX and XY embryos, 2) male embryos develop faster than female embryos to reach advanced stage and 3) degeneration of buffalo embryos is not linked with the paternal sex chromosome. We suggest that faster development of males is due to differential processing of X and Y chromosome within the zygote for its activation and / or differential expression of genes on paternal sex chromosome sex chromosome during development of buffalo embryos fertilized and cultured in vitro which may be attributed to a combination of genetic and environmental factors.

• 한국동물학회지
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• 제13권1호
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• pp.15-20
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• 1970

초파리의 성 염색체의 구성 여하에 따라 그 제 3염색체의 분리가 달라지는가를 조사하기 위하여 성 염색체의 구성이 다른 8가지 인자형을 만들고 제 3염색체 marker로서 e와 se를 이용하여 se의 분리를 k값으로 검토하고 아울러 성비를 조사 검토한 결과는 다음과 같다. 1. se의 분리 즉 k 값은 인자형간에 그리고 성간에 매우 유의적인 차를 보였으며 인자형과 성과의 상호작용도 유의적 차이를 보여 주었다. 이것은 분명히 se 제3염색체의 분리가 성 염색체의 구서에 영향을 받은 것을 말해 준다. 2. k(여) 값이나 k(남)값은 다 같이 인자형간에 유의적 차이를 볼 수 없다. 3. se자손의 성비는 인자형간에 매우 유의적 차이를 보였으나 e자손에서는 뚜렷한 차이를 볼수 없었다. 4. 평균적으로 k(남) 값은 k(여)값보다 높고, se자손의 성비는 e자손의 성비보다 높았다. 5. 이러한 결과는 어떤 종류의 prezygotic selection이 작용하는 것으로 해석할수 있는데, 즉 e 제3염색체와 Y염색체의 조합이 수정전에 감수되는 것으로 생각할 수 있다. 이러한 문제는 종래 초파리 등에서 실시했던 생존력 추정을 재 평가할 필요성을 말해주는 것이다.

• 한국동물학회지
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• 제39권1호
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• pp.75-88
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• 1996

OTF9-63 (OTF9)와 P19S1O1A1 (P19) 배종양 세포들의 체세포에 존재하는 불화성 X 염색체의 재활성과 유발 능력을 조사하였다. 배종야 세포와 체세포들의 융합에 의해 얻어진 HATr 클론들의 형태, 염색체 복제 양상을 비롯하여 X 염색체에 존재하나 그 위치는 상당히 먼 유전자들인 Hprt와 Pgk-1의 발현 양상을 분석한 결과, OTF9 세포는 불활성 X 염색체를 재활성화 시킬 수 있는데 반해 P19 세포는 불가능한 것으로 나타났다. 또한, 모든 유합세포는 장기간 배양되었을 때 성염색체의 수가 감소하였으며, 결국 1:2의 성염색체:상염색체의 비율을 나타내었다. 배종양 세포-체세포 융합세포의 이용은 초기 배발생 과정에서 시작되어 난자형성 과정의 감수분열 전까지의 유지되는 X 념색체의 재활성화 기작을 연구하기 위한 실험 방법을 제공한다.

• Toxicological Research
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• 제33권4호
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• pp.315-323
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• 2017

Preconceptual sex selection is still a highly debatable process whereby X- and Y-chromosome-bearing spermatozoa are isolated prior to fertilization of the oocyte. Although various separation techniques are available, none can guarantee 100% accuracy. The aim of this study was to separate X- and Y-chromosome-bearing spermatozoa using methods based on the viability difference between the X- and Y-chromosome-bearing spermatozoa. A total of 18 experimental semen samples were used, written consent was obtained from all donors and results were analysed in a blinded fashion. Spermatozoa were exposed to different pH values (5.5, 6.5, 7.5, 8.5, and 9.5), increased temperatures ($37^{\circ}C$, $41^{\circ}C$, and $45^{\circ}C$) and ROS level ($50{\mu}M$, $750{\mu}M$, and $1,000{\mu}M$). The live and dead cell separation was done through a modified swim-up technique. Changes in the sex-chromosome ratio of samples were established by double-label fluorescent in situ hybridization (FISH) before and after processing. The results indicated successful enrichment of X-chromosome-bearing spermatozoa upon incubation in acidic media, increased temperatures, and elevated $H_2O_2$. This study demonstrated the potential role for exploring the physiological differences between X-and Y-chromosome-bearing spermatozoa in the development of preconceptual gender selection.

• 한국가축번식학회지
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• 제20권2호
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• pp.179-190
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• 1996

Sexing and developing from splitted embryos which were fertilized in vitro implicate a possibility of production of the superior and sex controlled individuals. This study was carried out to investigate the production of transferable late blastocysts from in vitro fertilized embryos and to analyze sex by chromosome analysis from same embryos. In results, the ratio of cleavage and fertility of bovine follicular oocytes matured in vitro was 90% in co-cultured with granulosa cells. The competence of embryonic development from in vitro matured and fertilized bovine oocytes was 38% in co-cultured with bovine oviductal epithelial cells. To produce a lot of transferable embryos, therefore, the best conditon of culture system was co-cultured with granulosa cells for immature bovine oocytes and then co-cultured with bovine oviductal eptithelial cells for matured and fertilized oocytes. In chromosome analysis, 93% of in vitro fertilized embryos were very important aspect in chromosome preparation from bovine embryos such as duration of colcemid treatment, weakening of zona pellucida, methods of hypotonic treatment and fixation treatment.

• 한국수정란이식학회지
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• 제24권3호
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• pp.225-230
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• 2009

Sex-sorting of sperm is an assisted reproductive technology (ART) used by the livestock industry for the mass production of animals of a desired sex. The standard method for sorting sperm is the detection of DNA content differences between X and Y chromosome-bearing sperm by flow cytometry. However, this method has variable efficiency and therefore requires verification by a second method. We have developed a sex determination method based on quantitative real-time polymerase chain reaction (qPCR) of the porcine amelogenin (AMEL) gene. The AMEL gene is present on both the X and the Y chromosome, but the length and sequence of its noncoding regions differ between the X and Y chromosomes. By measuring the threshold cycle (Ct) of qPCR, we were able to calculate the relative frequency of X chromosome. Two sets of AMEL primers were used in these studies. One set (AME) targeted AMEL gene sequences present in both X and Y chromosome, but produced PCR products of different lengths for each chromosome. The other set (AXR) bound to AMEL gene sequences present on the X chromosome but absent esholthe Y-chromosome. Relative product levels were calculated by normalizing the AXR fluorescence to the AME fluorescence. The AMEL method accurately predicted the sex ratios of boar sperm, demonstrating that it has potential value as a sex determination method.

• 한국수정란이식학회지
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• 제11권3호
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• pp.283-289
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• 1996

This study was carried out to determine the sex of genomic and embryonic DNA using polymerase chain reaction(PCR). Bovine specific(216bp) and Y chromosome speicific DNA primers(l4lbp) were synthesized and tested for sexing. Bovine embryos used in this study were produced by in vitro fertilization. Few blastomeres for PCR were bisected by nicromanipulator and demi -embryos were cultured in TCM 199 medium containing 0.1% of solcoseryl. The results obtained were as follows; 1. Average optical density of genomic DNA extracted from blood of Hanwoo was 1.79$\pm$ 0.14. 2. 2. The ratio of the demi-embryos developed to blastocyst was 62.1 and 81.9% in morula and blastocyst, respectively. 3. When DNA of 2~4, 5~10 and more than 11 blastomeres was amplified with Y chromosome specific DNA primer by PCR, appreance rate of Y specific DNA band was 16.7, 46.2 and 40.0%, respectively. At least 5 to 10 blastomeres were required to determine the sex of embryos. 4. The rate of demi-embryos developed to blastocyst was 73.3% in TCM 199 medium supplemented with 0.1% solcoceryl. but 55.6% in control.

• 한국가축번식학회지
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• 제24권3호
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• pp.299-309
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• 2000

본 연구는 한우 체외수정란의 정확한 성판별을 위한 PCR의 적정조건을 검토하였고, Y 염색체 특이적 DNA primer(BOV97M : 141bp)와 소 특이적 DNA primer(216bp)를 이용한 2단계 PCR 방법으로 체외수정란의 발육속도에 따른 성판별율과 성비를 검토하였다. PCR 기법을 이용한 한우 체외수정란의 성판별은 Y 염색체 특이적 DNA primer와 소 특이적 DNA primer로 정확히 성을 판별할 수 있었으며, 웅성 수정란의 경우 141bp와 216bp에서 band가 나타났고, 자성 수정란의 경우 216bp에서 band가 나타났다. 한우 체외수정란의 경우 성판별 정확도를 높이기 위하여 투명대의 제거가 필요하며, 수정란의 DNA 추출방법에 따른 Y 염색체 특이적 band의 출현율은 Proteinase K와 반복 동결융해방법이 각각 45.2 및 53.3%로 나타났다. DNA의 양에 따른 성판별율은 zona free인 경우는 2$\mu$1와 10$\mu$1에서 각각 97.2%와 92.2% 였으며, zona intact의 경우는 12$\mu$1와 13$\mu$1에서는 각각 91.5%와 93.6%로서 zona free 수정란의 경우 2$\mu$1, zona intact의 경우 13$\mu$1의 DNA 양으로 성판별이 가능하였다. 한편, PCR 기법에 의한 한우 체외수정란의 성판별율은 96.0%였으며, 정확히 성판별을 할수 없는 비율은 4.0%였다. 성판별 수정란의 자성과 웅성의 비율은 46.3%와 49.7%로서 성비는 1.1:1이였으며, 발육단계간 자웅성비는 커다란 차이가 인정되지 않았으며, 발육단계가 진행될수록 성판별 정확도가 증가하였다.

• 한국가축번식학회지
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• 제20권4호
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• pp.443-451
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• 1997

These studies were conducted to determine the sex of preimplantation Hanwoo embryos produced in vitro using polymerase chain reaction(PCR). Y chromosome specific and bovine speicific DNA primers were synthesized and tested for embryo sexing. Bovine IVF embryos were produced in TCM 199 and CR1aa medium, and classified by developmental stages on Day 7 to 9. The effects of developmental rates to bovine IVF blastocysts on sex ratio were also investigated using PCR methods. The results obtained in this study were as follows; 1. Developmental rates to blastocyst from IVM/IVF embryos in TCM 199 and CR1aa medium for 9 days were 23.5 and 30.2%, respectively, and there was significant difference between the media(P<0.05). 2. Male to female ratio of early, mid, expanded and hatching balstocyst produced on Day 7 were 0.7:1, 1.4:1, 2.2:1, and 2.5:1, respectively, and male embryos was significantly higher proportion in expanding and hatching blastocysts(P<0.01). 3. On Day 8, male to female ratio of early, mid, expanded and hatching blastocysts were 0.6:1, 1:1, 2.5:1, and 2.7:1, respectively. Both expanded and hatching blastocysts obtained a significantly higher proportion of males(P<0.01). 4. The male : female ratio of early, mid, expanded and hatching blastocyst produced on Day 9 was 0.6:1, 0.8:1, 1:1, and 2.2:1, respectively. Hatching blastocysts had a significantly higher ratio of males(P<0.01). The developmental rate of IVM/IVF embryos to blastocyst for 9 day culture was higher in CR1aa than that in TCM 199 medium. For the sex ratio by developmental stages of IVF embryos, male ratio was higher in expanded blastocyst but female in early blastocysts.

• Asian-Australasian Journal of Animal Sciences
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• 제27권10호
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• pp.1411-1416
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• 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.