Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-24T07:20:25.711Z Has data issue: false hasContentIssue false

Frequency of sex chromosomal mosaicism in bovine embryos and its effects on sexing using a single blastomere by PCR

Published online by Cambridge University Press:  14 February 2003

Jong Ho Lee
Affiliation:
Institute of Animal Science and Technology, College of Agriculture and Life Sciences, Seoul National University, Suwon 441-744, Korea
Joong Hoon Park
Affiliation:
Institute of Animal Science and Technology, College of Agriculture and Life Sciences, Seoul National University, Suwon 441-744, Korea
Eun Joo Choi
Affiliation:
Institute of Genetic Engineering, College of Agriculture, Hankyong National University, Ansung, Korea
Jong Taek Yoon
Affiliation:
Institute of Genetic Engineering, College of Agriculture, Hankyong National University, Ansung, Korea
Chang Sik Park
Affiliation:
Division of Animal Science and Resources, Chungnam National University, Daejeon, Korea
Seong Ho Lee
Affiliation:
College of Visual Image & Health, Kongju National University, Kongju City, Korea
Kyung Soon Im
Affiliation:
Institute of Animal Science and Technology, College of Agriculture and Life Sciences, Seoul National University, Suwon 441-744, Korea
Dong Il Jin
Affiliation:
Department of Applied Biological Science, Sunmoon University, Asan City, 338-840, Korea

Abstract

Assessment of nuclear status is important when a biopsied single blastomere is used for embryo sexing. In this study we investigated the nuclear status of blastomeres derived from 8- to 16-cell stage in vitro fertilised bovine embryos to determine the representativeness of a single blastomere for embryo sexing. In 24 embryos analysed, the agreement in sex determination between a biopsied single blastomere and a matched blastocyst by polymerase chain reaction (PCR) was 83.3%. To clarify the discrepancies, karyotypes of blastomeres in 8- to 16-cell stage bovine embryos were analysed. We applied vinblastine sulfate at various concentrations and for different exposure times for metaphase plate induction in 8- to 16-cell stage bovine embryos. The 1.0 mg/ml vinblastine sulfate treatment for 15 h was selected as the most effective condition for induction of a metaphase plate (>45%). Among 22 embryos under these conditions, only 8 of 10 that had a normal diploid chromosome complement showed a sex chromosomal composition of XX or XY (36.4%) and 2 diploid embryos showed mosaicism of the opposite sex of XX and XY in blastomeres of the embryo (9.1%). One haploid embryo contained only one X-chromosome (4.5%). Four of another 11 embryos with a mixoploid chromosomal complement contained a haploid blastomere with a wrong sex chromosome (18.2%). In conclusion, assessment of nuclear status of 8- to 16-cell stage bovine embryos revealed that morphologically normal embryos had a considerable proportion of mixoploid blastomeres and sex chromosomal mosaicism; these could be the cause of discrepancies in the sex between biopsied single blastomeres and matched blastocysts by PCR.

Type
Research Article
Copyright
2003 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)