@article{dindot_farin_farin_romano_walker_long_piedrahita_2004, title={Epigenetic and genomic imprinting analysis in nuclear transfer derived Bos gaurus/Bos taurus hybrid fetuses}, volume={71}, DOI={10.1095/biolreprod.103.025775}, abstractNote={Abstract Somatic cell nuclear transfer (NT) in cattle is an inefficient process, whereby the production of calves is hindered by low pregnancy rates as well as fetal and placental abnormalities. Interspecies models have been previously used to facilitate the identification of single nucleotide polymorphisms (SNPs) within coding regions of genes to discriminate between parental alleles in the offspring. Here we report the use of a bovine interspecies model (Bos gaurus × Bos taurus) for the assessment and characterization of epigenetic modifications and genomic imprinting in Day 40-old female NT-derived fetuses and placenta. Analysis of NT and control pregnancies indicated disruption of genomic imprinting at the X inactivation-specific transcript (XIST) locus in the chorion, but not the fetus of clones, whereas proper allelic expression of the insulin-like growth factor II (IGF2) and gene trap locus 2 (GTL2) loci was maintained in both the fetus and placenta. Analysis of the XIST differentially methylated region (DMR) in clones indicated normal patterns of methylation; however, bisulfite sequencing of the satellite I repeat element and epidermal cytokeratin promoter indicated hypermethylation in the chorion of clones when compared with controls. No differences were detected in methylation levels in the fetus proper. These results indicate that the nuclear transfer process affects gene expression patterns in the trophectoderm- and inner cell mass-derived tissues to different extents.}, number={2}, journal={Biology of Reproduction}, author={Dindot, S. V. and Farin, P. W. and Farin, C. E. and Romano, J. and Walker, S. and Long, C. and Piedrahita, J. A.}, year={2004}, pages={470–478} }
 @article{piedrahita_mir_dindot_walker_2004, title={Somatic cell cloning: The ultimate form of nuclear reprogramming?}, volume={15}, ISSN={["1046-6673"]}, DOI={10.1097/01.ASN.0000110183.87476.05}, abstractNote={With the increasing difficulties associated with meeting the required needs for organs used in transplantation, alternative approaches need to be considered. These include the use of stem cells as potential sources of specialized cells, the ability to transdifferentiate cell types in culture, and the development of complete organs that can be used in humans. All of the above goals will require a complete understanding of the factors affecting cell differentiation and nuclear reprogramming. To make this a reality, however, techniques associated with cloning and genetic modifications in somatic cells need to be continued to be developed and optimized. This includes not only an enhancement of the rate of homologous recombination in somatic cells, but also a thorough understanding of the nuclear reprogramming process taking place during nuclear transfer. The understanding of this process is likely to have an effect beyond the area of nuclear transfer and assist with better methods for transdifferentiation of mammalian cells.}, number={5}, journal={JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY}, author={Piedrahita, JA and Mir, B and Dindot, S and Walker, S}, year={2004}, month={May}, pages={1140–1144} }