(July 2, 2012) -- In collaboration with scholars at the University of Hawaii at Honolulu and the University of Pennsylvania School of Medicine, researchers from The University of Texas at San Antonio Department of Biology have demonstrated in the laboratory for the first time that primary epigenetic mutations are corrected in the germ (sperm and egg) cells of mice.
The findings are critical because they confirm that environmental factors such as those involved in assisted reproductive technologies (ART) such as in vitro fertilization are likely to induce epimutations, but that these defects are subsequently corrected in the germ cells of the individuals produced by ART and so are not transmitted to subsequent generations.
The epigenome is the genetic programming that is responsible for gene expression, which ultimately decides one's outward appearance. Epimutations typically lead to changes in appearance or cellular function when they disrupt the normal function of one or more genes in a cell.
Over six years, UTSA scholar John McCarrey, the Robert and Helen Kleberg Distinguished Chair in Cellular and Molecular Biology, and two of his graduate students, Eric de Waal and Puraskar Ingale, studied three genes in mice artificially derived through a process called intracytoplasmic sperm injection (ICSI). They observed that half of these mice exhibited epigenetic mutations in their somatic cells.
Previous anecdotal observations had suggested that ICSI-derived mice do not pass on epimutations to their naturally conceived offspring. McCarrey and his collaborators wanted to find definitive evidence confirming this notion.
When the researchers allowed ICSI-derived mice that had epimutations in their somatic cells to breed naturally, they observed that the offspring had no epimuations. Their findings demonstrate that the epigenomes of the parent mice were reprogrammed at some point during the natural reproduction process.
Taken together, the science suggests that ART methods can cause epigenetic defects (epimutations) in the individuals produced by this method, but that if these individuals then reproduce naturally, their offspring will not display similar defects.
"The epigenome is made up of reversible modifications of genetic information, and these modifications are highly susceptible to environmental influences," said McCarrey. "There are more than 4 million humans alive today who were conceived by various forms of ART, and these individuals are at risk of having incurred epimutations during the ART process. The good news is that our data suggest that if these individuals reproduce naturally, their children are not likely to inherit these epigenetic defects."
Assisted reproductive technologies (ART) are becoming increasingly common worldwide and now account for two to three percent of human births. McCarrey and his team are continuing their research in an attempt to optimize ART methods so as to minimize the occurrence of epimutations in these individuals.
Take Back the Night is an international initiative to end violence. The event begins with banner making, followed by a march, presentations and poetry reading.
Sombrilla, Main Campus
Members of the UTSA community have published “Adapt and Overcome: Essays of the Student Veteran Experience,” an important book to help active duty military and veterans successfully transition to college life. The event includes a panel discussion with UTSA alumni student veterans who contributed chapters to the book. Guests can also purchase the book. All proceeds benefit the UTSA Student Veteran Association.
Business Building, University Room (BB 2.06.04), Main Campus
The Graduate School is hosting a panel discussion for all of our current students, alumni and members of the San Antonio community who are interested in learning more about graduate education.
Graduate School and Research Building (GSR 1.204), Main Campus
The annual UTSA Graduate fair gives students an opportunity to meet representatives who can provide the information on admission requirements, fellowship opportunities, and other key information.
University Center, Main Campus
A recruiter will speak to potential candidates for the Archer program. The Archer program has helped students land successful careers in public service.
Durango Building (DB 2.208), Downtown Campus
Canadian scholar Jasmin Hristov will present a lecture on paramilitarism, complex type of politically-motivated violence in different parts of Latin America. This presentation will explain paramilitary violence as a tool of economic globalization.
Buena Vista St. Bldg., Aula Canaria Lecture Hall (BV 1.328), Downtown Campus
The UTSA College of Engineering Technology Symposium showcases innovative student projects and research performed across multiple disciplines including engineering, science and business. The public is invited.
H-E-B UC Ballroom (HUC 1.104), Main Campus
The University of Texas at San Antonio is dedicated to the advancement of knowledge through research and discovery, teaching and learning, community engagement and public service. As an institution of access and excellence, UTSA embraces multicultural traditions and serves as a center for intellectual and creative resources as well as a catalyst for socioeconomic development and the commercialization of intellectual property - for Texas, the nation and the world.
To be a premier public research university, providing access to educational excellence and preparing citizen leaders for the global environment.
We encourage an environment of dialogue and discovery, where integrity, excellence, inclusiveness, respect, collaboration and innovation are fostered.