Aberrant gene expression patterns in placentomes of cattle cloned by somatic cell nuclear transfer

ABSTRACT: Transcription profiling of placentomes derived from somatic cell nuclear transfer (SCNT), in vitro fertilization (IVF) and artificial insemination (AI) at or near term development was performed in order to better understand why SCNT and IVF often result in placental defects, hydrops and large offspring syndrome (LOS). Multivariate analysis of variance was used to distinguish the effects of SCNT, IVF and AI on gene expression, taking into account the effects of parturition, sex of the fetus, breed of dam, breed of fetus and disease status of the offspring. The differential expression of 21 physiologically important genes was confirmed using quantitative PCR. The largest effect on placentome gene expression was attributable to whether placentae were collected at term or preterm (whether the collection was due to disease or to obtain matching case-controls) followed by placentome source (AI, IVF or SCNT). Gene expression in SCNT placentomes was dramatically different from AI (N=336 genes; 276 >2-fold) and from IVF (N=733 genes; 162 >2-fold) placentomes. Functional analysis of differentially expressed genes (DEG) showed that IVF has significant effects on genes associated with cellular metabolism. In contrast, DEG associated with SCNT are involved in multiple pathways, including cell cycle, cell death, gene expression, posttranslational modification, molecular transport and connective tissue development. Many DEG were shared between the gene lists for IVF and SCNT comparisons, suggesting that common pathways are affected by the embryo culture methods used for IVF and SCNT. However, the many unique gene functions and pathways affected by SCNT suggest that cloned fetuses may be starved and accumulating toxic wastes due to placental insufficiency caused by reprogramming errors. Many of these genes are candidates for hydrops and LOS. Keywords: gene expression; development; SCNT; cloning; nuclear transfer; IVF; AI

ORGANISM(S): Bos taurus

PROVIDER: GSE8923 | GEO | 2007/12/21

SECONDARY ACCESSION(S): PRJNA102331

REPOSITORIES: GEO