Cell cycle and histone modification genes were decreased in placenta tissue from unexplained early miscarriage.

Genetic defect is a major cause of early miscarriage, but still in many cases the etiology are not fully understood. Recent studies have shown that dysregulation of genes in placenta tissue are participated in the pathogenesis of unexplained early miscarriage. The aim of our study is to explore mRNA expression profile in placental chorionic villi and to reveal the underlying mechanism of unexplained early miscarriage. Chorionic villous were isolated and extracted from early miscarriage (n=3) and control pregnancy (n=3) placenta with normal chromosome karyotype using MLPA assay, and then mRNA expression profiles were determined by microarray. For verification the reproducibility of the microarray, three up-regulated genes and six down-regulated genes were chosen and examined by real-time PCR (n=30). A total of 81 genes were up-regulated and 231 genes were down-regulated when compared to the control group, and the differences were reached statistically significances (P<0.05). After Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, we found that almost down-regulation genes are associated with cell cycle and histone modification, and these genes are participated in several important physiological processes, such as cell proliferation, nuclear division, chromatic assembly, DNA packing and modification. These results indicated that cell cycle and histone modification genes, and related signaling pathway maybe contribute to the genesis and development of unexplained early miscarriage. Further studies and validations are necessary to elucidate the exact roles of these genes in miscarriage pathogenesis, which can develop tools for early detection and management.