Mice chimeric for embryonic stem (ES) cells have not always successfully produced ES-derived offspring. Here we show that the male gametes from ES cells could be selected in male chimeric mice testes by labeling donor ES cells or host blastocytes with GFP. Male GFP-expressing ES-derived germ cells o
Germ cell chimerism in male marmosets
β Scribed by Suzanne H. Hampton
- Publisher
- John Wiley and Sons
- Year
- 1973
- Tongue
- English
- Weight
- 356 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0002-9483
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Marmosets normally produce biovular twins which are connected, via placental vascular anastomoses, as early as preβsomite stages of development. These anastomoses allow the exchange of lymphoid and hematopoietic tissue, as demonstrated by karyotype analysis in heterosexual twins. Because germ cells are also motile during development, i.e., they migrate from the yolk sac endodermal epithelium to the germinal ridges, the possibility exists that germ cells could also be exchanged between heterosexual twins. Testicular squash preparations were examined from 22 adult male marmosets of several species. During the diakinesis stage of meiotic prophase the XY chromosome pair was distinct. Spermatocytes which lacked the conspicuous endβtoβend association of the XY pair were considered to have originated from germ cells with an XX sex chromosome constitution. In approximately half the animals examined, all diakinesis figures contained an endβtoβend XY pair. In the remaining animals, primary spermatocytes were seen that clearly did not contain an endtoβend XY pair. The largest number of such XX primary spermatocytes in any one animal was 21% (9 of 43 cells examined). The effects of germ cell chimerism on the sex ratio of offspring was also investigated.
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