Intrauterine growth restriction modifies gene expression profiling in cord blood

Background: Small-for-gestational-age (SGA) newborns are at an increased risk for perinatal morbidity and mortality and development of metabolic syndromes such as cardiovascular disease and type 2 diabetes mellitus (T2DM) in adulthood. The mechanism underlying this increased risk remains unclear. In this study, genetic modifications of cord blood were investigated to characterize fetal change in SGA newborns. Methods: Gene expression in cord blood cells was compared between 10 SGA newborns and 10 appropriate-for-gestational-age (AGA) newborns using microarray analysis. Pathway analysis was conducted using the Ingenuity Pathways Knowledge Base. To confirm the microarray analysis results, quantitative real-time polymerase chain reaction (RT-PCR) was performed for upregulated genes in SGA newborns. Results: In total, 775 upregulated and 936 downregulated probes were identified in SGA newborns and compared with those in AGA newborns. Of these probes, 1149 were annotated. Most of these genes have been implicated in the development of cardiovascular disease and T2DM. There was good agreement between the RT-PCR and microarray analyses results. Conclusions: Expression of certain genes was modified in SGA newborns in the fetal period. These genes have been associated with metabolic syndrome. To clarify the association between modified gene expression in cord blood and individual vulnerability to metabolic syndrome in adulthood, these SGA newborns will be have long-term follow up for examination of genetic and postnatal environmental factors. Gene expression of cord blood can be a useful and non-invasive method of investigation of genetic alterations in the fetal period.