Conserved roles of mouse DUX and human DUX4 in activating cleavage-stage genes and MERVL/HERVL retrotransposons.

To better understand transcriptional regulation during human oogenesis and preimplantation development, we defined stage-specific transcription, which highlighted the cleavage stage as being highly distinctive. Here, we present multiple lines of evidence that a eutherian-specific multicopy retrogene, DUX4, encodes a transcription factor that activates hundreds of endogenous genes (for example, ZSCAN4, KDM4E and PRAMEF-family genes) and retroviral elements (MERVL/HERVL family) that define the cleavage-specific transcriptional programs in humans and mice. Remarkably, mouse Dux expression is both necessary and sufficient to convert mouse embryonic stem cells (mESCs) into 2-cell-embryo-like ('2C-like') cells, measured here by the reactivation of '2C' genes and repeat elements, the loss of POU5F1 (also known as OCT4) protein and chromocenters, and the conversion of the chromatin landscape (as assessed by transposase-accessible chromatin using sequencing (ATAC-seq)) to a state strongly resembling that of mouse 2C embryos.

Comparison of 5% and ambient oxygen during days 3-5 of in vitro culture of human embryos.

Objective: To compare the effect of two oxygen concentrations used during days 3-5 of human embryo culture on embryo quality and pregnancy outcome.

Design: Retrospective analysis of the use of two culture conditions.

Setting: University-based infertility clinic.

In vitro oocyte maturation and subsequent delayed fertilization is associated with increased embryo aneuploidy.

Failed fertilization and the appearance of immature oocytes are common in IVF practice; rescue intracytoplasmic sperm injection can be used as a therapy. However, this study indicates that embryos created after in vitro maturation and delayed intracytoplasmic sperm injection contain an increase in aneuploidy (79.7%) over control embryos (60.

Comparison of four media types during 3-day human IVF embryo culture.

The aim of this study was to compare the effectiveness of human tubal fluid (HTF), G1.2, Sage Cleavage and Life Global media for IVF outcome during 3-day culture of human embryos. A three-phase auto-controlled study was conducted in which IVF outcome was compared between (1) HTF and G1.

Improved in vitro fertilization embryo quality and pregnancy rates with intracytoplasmic sperm injection of sperm from fresh testicular biopsy samples vs. frozen biopsy samples.

Objective: To compare the outcomes of first-attempt IVF-intracytoplasmic sperm injection (ICSI) cycles when using fresh testicular biopsy samples vs. frozen biopsy samples.

Design: Retrospective chart review of 92 consecutive first-attempt IVF-ICSI cycles.

Elevated sperm chromosome aneuploidy and apoptosis in patients with unexplained recurrent pregnancy loss.

Objective: To evaluate sperm chromosome aneuploidy and semen quality in 24 partners of women with unexplained recurrent pregnancy loss and to analyze the data in relation to sperm apoptosis data.

Methods: Semen quality parameters and sperm chromosome aneuploidy for chromosomes X, Y, 13, 18, and 21 were evaluated in the recurrent pregnancy loss patients, fertile controls, and a control group of men from the general population.

Results: The mean aneuploidy rate in the recurrent pregnancy loss group was 2.