Institution
The Roslin Institute
Facility•Dalkeith, United Kingdom•
About: The Roslin Institute is a facility organization based out in Dalkeith, United Kingdom. It is known for research contribution in the topics: Population & Gene. The organization has 1017 authors who have published 1780 publications receiving 99880 citations.
Papers published on a yearly basis
Papers
More filters
••
TL;DR: The birth of lambs from differentiated fetal and adult cells confirms that differentiation of that cell did not involve the irreversible modification of genetic material required for development to term and reinforces previous speculation that by inducing donor cells to become quiescent it will be possible to obtain normal development from a wide variety of differentiated cells.
Abstract: Fertilization of mammalian eggs is followed by successive cell divisions and progressive differentiation, first into the early embryo and subsequently into all of the cell types that make up the adult animal. Transfer of a single nucleus at a specific stage of development, to an enucleated unfertilized egg, provided an opportunity to investigate whether cellular differentiation to that stage involved irreversible genetic modification. The first offspring to develop from a differentiated cell were born after nuclear transfer from an embryo-derived cell line that had been induced to become quiescent. Using the same procedure, we now report the birth of live lambs from three new cell populations established from adult mammary gland, fetus and embryo. The fact that a lamb was derived from an adult cell confirms that differentiation of that cell did not involve the irreversible modification of genetic material required for development to term. The birth of lambs from differentiated fetal and adult cells also reinforces previous speculation that by inducing donor cells to become quiescent it will be possible to obtain normal development from a wide variety of differentiated cells.
4,721 citations
••
TL;DR: This is the first report, to the authors' knowledge, of live mammalian offspring following nuclear transfer from an established cell line, and will provide the same powerful opportunities for analysis and modification of gene function in livestock species that are available in the mouse through the use of embryonic stem cells.
Abstract: Nuclear transfer has been used in mammals as both a valuable tool in embryological studies and as a method for the multiplication of 'elite' embryos. Offspring have only been reported when early embryos, or embryo-derived cells during primary culture, were used as nuclear donors. Here we provide the first report, to our knowledge, of live mammalian offspring following nuclear transfer from an established cell line. Lambs were born after cells derived from sheep embryos, which had been cultured for 6 to 13 passages, were induced to quiesce by serum starvation before transfer of their nuclei into enucleated oocytes. Induction of quiescence in the donor cells may modify the donor chromatin structure to help nuclear reprogramming and allow development. This approach will provide the same powerful opportunities for analysis and modification of gene function in livestock species that are available in the mouse through the use of embryonic stem cells.
1,874 citations
••
TL;DR: Ovine primary fetal fibroblasts were cotransfected with a neomycin resistance marker gene (neo) and a human coagulation factor IX genomic construct designed for expression of the encoded protein in sheep milk and produced viable animals by nuclear transfer.
Abstract: Ovine primary fetal fibroblasts were cotransfected with a neomycin resistance marker gene (neo) and a human coagulation factor IX genomic construct designed for expression of the encoded protein in sheep milk. Two cloned transfectants and a population of neomycin (G418)-resistant cells were used as donors for nuclear transfer to enucleated oocytes. Six transgenic lambs were liveborn: Three produced from cloned cells contained factor IX and neo transgenes, whereas three produced from the uncloned population contained the marker gene only. Somatic cells can therefore be subjected to genetic manipulation in vitro and produce viable animals by nuclear transfer. Production of transgenic sheep by nuclear transfer requires fewer than half the animals needed for pronuclear microinjection.
996 citations
••
TL;DR: It is argued that epistasis should be accounted for in complex trait studies; current study designs for detecting epistasis are critically assessed and how these might be adapted for use in additional populations, including humans.
Abstract: Interactions among loci or between genes and environmental factors make a substantial contribution to variation in complex traits such as disease susceptibility. Nonetheless, many studies that attempt to identify the genetic basis of complex traits ignore the possibility that loci interact. We argue that epistasis should be accounted for in complex trait studies; we critically assess current study designs for detecting epistasis and discuss how these might be adapted for use in additional populations, including humans.
936 citations
••
TL;DR: Four different situations have been identified that result in the large offspring syndrome: in vitro embryo culture, asynchronous embryo transfer into an advanced uterine environment, nuclear transfer and maternal exposure to excessively high urea diets.
Abstract: Bovine and ovine embryos exposed to a variety of unusual environments prior to the blastocyst stage have resulted in the development of unusually large offspring which can also exhibit a number of organ defects. In these animals, the increased incidence of difficult parturition and of fetal and neonatal losses has limited the large-scale use of in vitro embryo production technologies commonly used in humans and other species. Four different situations have been identified that result in the syndrome: in vitro embryo culture, asynchronous embryo transfer into an advanced uterine environment, nuclear transfer and maternal exposure to excessively high urea diets. However, programming of the syndrome by all of these situations is unpredictable and not all of the symptoms described have been observed universally. Neither the environmental factors inducing the large offspring syndrome nor the mechanisms of perturbation occurring in the early embryo and manifesting themselves in the fetus have been identified.
912 citations
Authors
Showing all 1037 results
Name | H-index | Papers | Citations |
---|---|---|---|
John P. A. Ioannidis | 185 | 1311 | 193612 |
Peter W.F. Wilson | 181 | 680 | 139852 |
Peter M. Visscher | 143 | 694 | 118115 |
David A. Hume | 113 | 573 | 59932 |
Jan O. Korbel | 81 | 204 | 45584 |
Marylyn D. Ritchie | 80 | 459 | 32559 |
Gail Davies | 79 | 237 | 24998 |
Christopher J. Mungall | 76 | 242 | 40589 |
Michael Jones | 72 | 331 | 18889 |
Chris Haley | 71 | 410 | 23592 |
Olivier Pourquié | 71 | 226 | 19070 |
Ian Wilmut | 67 | 263 | 24508 |
Albert Tenesa | 65 | 165 | 18865 |
Ilias Kyriazakis | 64 | 380 | 14566 |
Tom C. Freeman | 63 | 255 | 18744 |