Featured Research

from universities, journals, and other organizations

Human Embryonic Stem Cells Derived From Preimplantation Genetically Diagnosed Embryos

Date:
November 15, 2007
Source:
Cell Press
Summary:
A human stem cell line derived from embryos that were identified by preimplantation genetic diagnosis to carry the mutation for fragile X syndrome has provided an unprecedented view of early events associated with this disease. In addition to giving scientists fresh insight into fragile X, results from this unique model system have emphasized the value of this new source of embryonic stem cells and may have a significant impact on the way that genetic diseases are studied in the future.

A human stem cell line derived from embryos that were identified by preimplantation genetic diagnosis (PGD) to carry the mutation for fragile X syndrome has provided an unprecedented view of early events associated with this disease. In addition to giving scientists fresh insight into fragile X, results from this unique model system have emphasized the value of this new source of embryonic stem cells and may have a significant impact on the way that genetic diseases are studied in the future.

Fragile X syndrome, the most common cause of inherited mental impairment and of autism, is caused by the absence of the fragile X mental retardation protein (FMRP). Most individuals with fragile X exhibit a specific mutation in the fragile X mental retardation 1 (FMR1) gene that usually coincides with epigenetic DNA modifications. However, the developmental timing and mechanisms associated with acquisition of these characteristics are not clear due to the absence of appropriate cellular and animal models.

To examine developmentally regulated events involved in fragile X pathogenesis, Dr. Nissim Benvenisty and Dr. Rachel Eiges from the Hebrew University Department of Genetics in Jerusalem, Israel, together with Dr. Dalit Ben-Yosef from the IVF unit at the Tel-Aviv Sourasky Medical Center, established a human embryonic stem cell (HESC) line from a preimplantation fragile X-affected embryo identified by PGD. The fragile X cell line, called HEFX, displayed all characteristics typical of an HESC line and possessed the full genetic mutation observed in fragile X patients.

The researchers found that undifferentiated HEFX cells transcribed FMR1 and expressed FMRP, suggesting that the fragile X mutation by itself is not sufficient to cause FMR1 inactivation. The research team went on to show that differentiated derivatives of HEFX cells exhibited a decrease in FMRI transcription and FMRP expression along with an increase in epigenetic modifications associated with fragile X syndrome. "The fact that FMR1 inactivation and other modifications take place after differentiation suggests that it might be possible to prevent some of these events as an attempt to rescue the abnormal phenotype in cells with the full fragile X mutation," suggests Dr. Benvenisty.

HEFX cells represent an excellent model for examination of early embryogenesis and will contribute to a clearer understanding of the molecular mechanisms underlying fragile X pathogenesis. This research is also compelling on a more general level in that it validates the usefulness of HESCs derived from embryos that have been screened for specific mutations with PGD. ESC lines derived in this manner represent a potent tool for the study of a variety of human diseases and the development of new therapeutic strategies.

The research is published in the November issue of the journal Cell Stem Cell, published by Cell Press.

The researchers include Rachel Eiges, Achia Urbach, Amir Eden, Ofra Yanuka, andNissim Benvenisty, of the Silberman Institute of Life Science, The Hebrew University, Jerusalem, Israel; Mira Malcov, Tsvia Frumkin, Tamar Schwartz, Dalit Ben-Yosef, Ami Amit, and Yuval Yaron, of the Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel.


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Cite This Page:

Cell Press. "Human Embryonic Stem Cells Derived From Preimplantation Genetically Diagnosed Embryos." ScienceDaily. ScienceDaily, 15 November 2007. <www.sciencedaily.com/releases/2007/11/071114121328.htm>.
Cell Press. (2007, November 15). Human Embryonic Stem Cells Derived From Preimplantation Genetically Diagnosed Embryos. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2007/11/071114121328.htm
Cell Press. "Human Embryonic Stem Cells Derived From Preimplantation Genetically Diagnosed Embryos." ScienceDaily. www.sciencedaily.com/releases/2007/11/071114121328.htm (accessed August 21, 2014).

Share This




More Health & Medicine News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
American Ebola Patients Released: What Cured Them?

American Ebola Patients Released: What Cured Them?

Newsy (Aug. 21, 2014) It's unclear whether the American Ebola patients' recoveries can be attributed to an experimental drug or early detection and good medical care. Video provided by Newsy
Powered by NewsLook.com
Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins