Comparative analysis of single-cell parallel sequencing approaches in oocyte application.

Single-cell parallel sequencing allows us to explore how genetic and epigenetic variations correlate of gene expression in the same cell. Beads-based approach and non-beads-based approach are the two present methods to separate DNA and RNA from the same cell. However, systematic difference between the two methods are lacking. In our study, we compared the performances of the two methods using transcriptome and methylome profiles generated simultaneously from single mouse oocytes. Our results showed that the beads-based approach could capture maximum quantity of mRNA but loss of DNA was inevitable, while the non-beads-based approach could obtain more DNA due to the undamaged nucleus obtained but at a cost of partial loss of mRNA. As the sequencing coverage of methylome sequencing in a single cell was relatively low, single-cell whole genome bisulfite sequencing (scWGBS) was preferable to generate the methylome map in single-cell parallel sequencing in comparison to single-cell reduced representation bisulfite sequencing (scRRBS). To the best of our knowledge, this is the first study to compare the two methods of single-cell parallel sequencing which offers a basic idea for deciding between the two methods and a direction of single-cell parallel sequencing development.

Effect of mid-follicular phase recombinant LH versus urinary HCG supplementation in poor ovarian responders undergoing IVF - a prospective double-blinded randomized study.

Luteinizing hormone (LH) is crucial for the development of follicular growth and oocyte maturation, especially in the management of poor ovarian responders (PORs). This study presents the results of a prospective double-blinded randomized study to compare the effect of mid-follicular phase recombinant LH (rLH) supplementation with urinary human chorionic gonadotrophin (uHCG) supplementation when using a fixed gonadotrophin-releasing hormone (GnRH) antagonist protocol in IVF cycles. A total of 49 women with poor ovarian response (POR) according to the Bologna criteria were recruited. This study showed no statistically significant difference in cycle cancellation rates, numbers of oocytes retrieved per cycle initiated, fertilization rates, the numbers of embryos obtained per cycle initiated, implantation, clinical pregnancy and live birth rates, although the live birth rate per cycle initiated in the uHCG group (29.2%) was 3.6 times that of the rLH group (8.0%). Further studies are required to verify if uHCG supplementation produces better clinical outcomes compared with rLH in women with POR.