Mouse stem cell line advance suggests potential for IVF-incompetent eggs

Feb 19, 2007

Researchers have found that mouse oocytes that fail to become fertilized during in vitro fertilization are nevertheless often capable of succeeding as "cytoplasmic donors" during a subsequent cloning step using so-called nuclear transfer. Although the implications for human eggs are not yet clear, the findings are of interest because of the ethical and practical concerns surrounding the need for fresh human oocytes for similar nuclear-transfer procedures using human cells.

The findings, reported by Teruhiko Wakayama, Sayaka Wakayama, and colleagues at RIKEN Kobe in Japan, appear in the February 20th issue of the journal Current Biology, published by Cell Press.

Human IVF is now routinely practiced in fertility clinics, but a proportion of oocytes fail to become fertilized in these procedures. In the new work, researchers examined the ability of day-old mouse oocytes that fail to become fertilized in vitro—"aged, fertilization-failure" (or AFF) oocytes—to succeed in a standard cloning procedure in which the oocyte's nucleus is removed and replaced by the nucleus of a somatic cell. Although this nuclear-transfer procedure showed a lower rate of success in the very first stages of cloning compared to nuclear transfer with fresh oocytes, the early (morulae- or blastocyst-stage) mouse embryos derived from nuclear transfer using AFF oocytes showed similar rates of success in giving rise to embryonic stem cell lines.

None of the AFF-derived mouse embryos tested were capable of developing to full term, and in general, cloning by nuclear transfer sees a low success rate even when fresh eggs are used. But the authors indicate that nuclear-transfer protocols have yet to be perfected, and that the new findings suggest that once techniques required for human nuclear transfer have been optimized, it may be possible to use oocytes that failed to fertilize during IVF attempts and would otherwise be discarded.

Source: Cell Press

Explore further: New study advances 'DNA revolution,' tells butterflies' evolutionary history

add to favorites email to friend print save as pdf

Related Stories

Fermi satellite detects gamma-rays from exploding novae

1 hour ago

The Universe is home to a variety of exotic objects and beautiful phenomena, some of which can generate almost inconceivable amounts of energy. ASU Regents' Professor Sumner Starrfield is part of a team that ...

NASA sees Genevieve squeezed between 3 tropical systems

1 hour ago

The resurrected Tropical Depression Genevieve appears squeezed between three other developing areas of low pressure. Satellite data from NOAA and NASA continue to show a lot of tropical activity in the Eastern ...

US warns retailers on data-stealing malware

1 hour ago

US government cybersecurity watchdogs warned retailers Thursday about malware being circulated that allows hackers to get into computer networks and steal customer data.

Recommended for you

The 'memory' of starvation is in your genes

2 hours ago

During the winter of 1944, the Nazis blocked food supplies to the western Netherlands, creating a period of widespread famine and devastation. The impact of starvation on expectant mothers produced one of the first known ...

Brother of Hibiscus is found alive and well on Maui

5 hours ago

Most people are familiar with Hibiscus flowers- they are an iconic symbol of tropical resorts worldwide where they are commonly planted in the landscape. Some, like Hawaii's State Flower- Hibiscus brackenridgei- are en ...

User comments : 0