Gene expression in women conceiving spontaneously over the age of 45 years

ObjectiveTo examine gene expression profiles of women conceiving spontaneously after the age of 45.DesignExpression profiling by complementary DNA microarray analysis.SettingUniversity departments.Patient(s)Eight women 45 years or older (study group) who conceived spontaneously and were 6 months after their last delivery were compared with six women aged 45 years old (control group) who had their last delivery before the age of 30.Intervention(s)Blood samples were collected from each woman for RNA isolation from peripheral blood mononuclear cells (PBMC).Main Outcome Measure(s)Expression profiles of PBMC isolated from each woman were determined by using Affymetrix DNA microarray analysis covering about 15,000 identified genes.Result(s)Microarray of global gene expression revealed 671 genes that showed statistically significant differential expression between the study and control groups: 383 genes were overexpressed and 288 were underexpressed. The most significant functional groups defining these genes were: apoptosis, ubiquitination, and energy production. As many as 60 genes also participated in ovarian physiology.Conclusion(s)These observations suggest that extended fertility is associated with a unique ability to enrich cellular processes, leading to delayed ovarian senescence.