International Collaborative Study Provides Insight into Gene Activation in One-Cell Embryos

Nashville, Tenn., Dec. 28, 2021 (GLOBE NEWSWIRE) — IVF services company Ovation Fertility announces the publication of a new collaborative study, “Human embryonic genome activation initiates at the one-cell stage.” The groundbreaking study reveals that genes in human embryos rapidly become active soon after fertilization, at the single-cell stage, rather than at the multicell stage as previously believed. A summary of the research is now available online at OvationFertility.com and at Cell Stem Cell.

The international study was co-led by Professor Tony Perry PhD, Department of Biology and Biochemistry, University of Bath, Giles Yeo PhD, MBE, University of Cambridge, and Matthew VerMilyea, PhD, HCLD/CC at Ovation Fertility.

“It was previously thought that genes do not become active in human embryos until two or three days after fertilization, when an embryo has four to eight cells,” says Matthew “Tex” VerMilyea, PhD, HCLD/CC, Ovation’s vice president of scientific advancement. “Our research revealed that in fact, genetic activity begins when an embryo is just one cell. We also found that gene activation mirrors early embryonic processes, is disrupted in abnormal embryos, and predicts links to cancer-associated transcription regulators. The more we can understand about the process of genome awakening, the better we can understand genetic inheritance, infertility and disease. These are very exciting findings that have implications for epigenetic inheritance as well as stem-cell-derived embryos and cancer.”

Using highly sensitive, state-of-the-art RNA sequencing, the team applied precision analysis to individual human eggs and one-cell embryos, creating a detailed inventory of the RNA transcripts produced by gene activity. This process, which was sensitive enough to reveal even small changes in gene activity, found that hundreds of genes awaken in human one-cell embryos.

Additionally, the international research team discovered that many genes activated in single-cell embryos stay switched on until the embryo reaches four to eight cells, then switch off. Some genes that are activated early may play specific roles in early embryos, but because the roles of some genes are unknown, more research is needed to understand their impact on embryonic development. Now that the earliest embryonic genes have been identified, future research can focus on how genetic activation is triggered, and the role that the egg plays in genetic activation.

Because it is believed that certain factors that trigger gene activation are also associated with cancer, the researchers speculate that the natural role of factors known to misbehave in cancer is to awaken genes in one-cell embryos. While further research is needed to verify this link, this study’s findings could help clarify the events that initiate cancer, leading to new opportunities for diagnostic and preventive advances.

This research also has implications for inheritance of acquired traits, such as obesity. Scientists don’t yet understand how acquired traits are transmitted, but the research team speculates that altering gene activation after fertilization could play a role, and may be detectable at the one-cell stage of embryo development.

By examining the genetic makeup of one-cell embryos that did not continue to develop, the study’s researchers also found that many of their genes failed to activate. This finding suggests that abnormal embryos should not be used to evaluate methods of heritable genome editing, as they have been in the past.

Learn more about Ovation research at OvationFertility.com/Research.

About Ovation Fertility
Ovation® Fertility is a national network of reproductive endocrinologists and scientific thought leaders focused on reducing the cost of having a family through more efficient and effective fertility care. Ovation’s IVF and genetics laboratories, along with affiliated physician practices, work collaboratively to raise the bar for IVF treatment, with state-of-the-art, evidence-based fertility services that give hopeful parents the best chance for a successful pregnancy. Physicians partner with Ovation to offer their patients advanced preconception carrier screening; preimplantation genetic testing; donor egg and surrogacy services; and secure storage for their frozen eggs, embryos and sperm. Ovation also helps IVF labs across America improve their quality and performance with expert off-site lab direction and consultation. Learn more about Ovation’s vision of a world without infertility at www.OvationFertility.com.

University of Bath
The University of Bath is one of the UK’s leading universities both in terms of research and its reputation for excellence in teaching, learning and graduate prospects. The university is rated Gold in the Teaching Excellence Framework (TEF), the Government’s assessment of teaching quality in universities, meaning its teaching is of the highest quality in the UK. In the Research Excellence Framework (REF) 2014 research assessment, 87 percent of its research was defined as “world-leading” or “internationally excellent.” From developing fuel-efficient cars of the future, to identifying infectious diseases more quickly, or working to improve the lives of female farmers in West Africa, research from Bath is making a difference around the world.  Well established as a nurturing environment for enterprising minds, Bath is ranked highly in all national league tables. We are ranked 8th in the UK by The Guardian University Guide 2022, and 9th in The Times & Sunday Times Good University Guide 2022 and 10th in the Complete University Guide 2022. Our sports offering was rated as being in the world’s top 10 in the QS World University Rankings by Subject in 2021. Find out more at www.bath.ac.uk/topics/research/.

 About the MRC Metabolic Diseases Unit
The MRC Metabolic Diseases Unit is based at the Wellcome-MRC Institute of Metabolic Science. It supports research to improve understanding of the basic mechanisms responsible for obesity and related metabolic diseases. This knowledge underpins the development of interventions to prevent and treat these conditions.

About the University of Cambridge
The University of Cambridge is one of the world’s top 10 leading universities, with a rich history of radical thinking dating back to 1209. Its mission is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence. The university comprises 31 autonomous colleges and 150 departments, faculties and institutions. Its 24,450 student body includes more than 9,000 international students from 147 countries. In 2020, 70.6% of its new undergraduate students were from state schools and 21.6% from economically disadvantaged areas. Cambridge research spans almost every discipline, from science, technology, engineering and medicine through to the arts, humanities and social sciences, with multidisciplinary teams working to address major global challenges. Its researchers provide academic leadership, develop strategic partnerships and collaborate with colleagues worldwide. The university sits at the heart of the “Cambridge cluster,” in which more than 5,300 knowledge-intensive firms employ more than 67,000 people and generate £18 billion in turnover. Cambridge has the highest number of patent applications per 100,000 residents in the UK.  Learn more at www.cam.ac.uk.

• Matthew “Tex” VerMilyea, PhD, HCLD/CC