Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First babies born from genetic screening study

18.10.2010
Births in Italy and Germany from eggs tested by CGH

Two women taking part in the world's first controlled study of a comprehensive genetic screening test before IVF have given birth to healthy babies.

The babies, twin girls born in Germany in June and a singleton boy born in Italy in September, are the first deliveries in a pilot study of comparative genomic hybridisation (CGH) by microarray, a new method of screening oocytes for IVF for a full range of chromosomal disorders.

Dr Cristina Magli, embryologist at the SISMER Centre in Bologna, one of the two centres taking part in the trial, said: " All the babies and their mothers are doing very well in terms of weight and overall developmental performance."

The births, as well as several ongoing pregnancies in the study group, are the final stage in the "proof of principle" that the screening of oocytes and embryos before transfer in IVF can increase birth rates; both these pregnancies were derived from oocytes whose complete chromosomal status had been assessed by microarray CGH.

The study, which was conducted in Bologna, Italy, and Bonn, Germany, was designed and organised by a task force of ESHRE to determine the clinical value of CGH as a non-subjective means of genetic screening before embryo transfer.

"We have learnt from more than 30 years of IVF that many of the embryos we transfer have chromosome abnormalities," explains ESHRE's chairman Luca Gianaroli. "Indeed, it's still the case that two out of every three embryos we transfer fail to implant as a pregnancy, many of them because of these abnormalities.

"The whole world of IVF has been trying to find an effective way of screening for these abnormalities for more than a decade, but results so far have been disappointing with the technology available. Now we have a new technology in array CGH and our hopes are that this will finally provide a reliable means of assessing the chromosomal status of the embryos we transfer."

The microarray CGH technique as evaluated in the ESHRE study has several advantages over other methods:

CGH tests all 23 pairs of chromosomes in a cell, and not just a limited number (as in former methods)

The cell tested (known as the polar body) is taken from an oocyte at fertilisation, and so does not require biopsy of a cell from a developing embryo for its analysis

Earlier chromosome tests were on cells biopsied from growing embryos and did not necessarily reflect the total status of the embryo (because of chromosome "mosaicism"); polar body analysis removes this potential problem

Other CGH tests on biopsies from five-day-old embryos require several days to deliver complete results - and thus require the freeze-storage of the embryo before it can be transferred; polar body CGH can be done in real time and does not require freezing

At the everyday clinical level, polar body CGH is likely to have two more important consequences: first, because the analysis is performed on oocytes and not on embryos, countries like Germany which outlaw embryo analysis and freezing will now have at their disposal a reliable method of preimplantation genetic screening; and second, because the chromosomal status of the transferred embryo can be accurately predicted (with no more than a 10 per cent error rate as found in the ESHRE study), the reduction of multiple pregnancies in IVF by single embryo transfer will become more attractive.

In the short term, the IVF patients most likely to benefit from preimplantation screening by polar body CGH are those of an older maternal age (over 37 years), those with a record of unsuccessful IVF, and those with a history of miscarriage; all these conditions are associated with a higher than average rate of embryonic chromosomal abnormality.

"The study has already caused huge interest in the scientific and clinical community," says Dr Magli, "and we are very proud to announce these results. It is the first time that a scientific society like ESHRE has organised a study to determine the clinical value of a technique which could prove a revolution in IVF."

The next step for ESHRE will be to upgrade the pilot study into a large-scale international clinical trial, which is planned to start in 2011.

Notes for editors

1. The pilot study was performed at the SISMER centre in Bologna, Italy (Professor Luca Gianaroli, chairman of ESHRE, and Dr Cristina Magli), and the University of Bonn, Germany (Dr Markus Montag and Professor Hans van der Ven). All data from the study were independently collected and analysed by Sjoerd Repping from the Academic Medical Centre in Amsterdam.

2. Results of validating the accuracy of the pilot study analysis were presented at ESHRE's 2010 annual meeting in Rome. They showed that 23-chromosome testing of both polar bodies with array CGH can be completed within 12-13 hours (thereby allowing for fresh transfer), and that the reliable identification of the chromosomal status of an oocyte is possible in almost 90 per cent of attempts.

3. The average age of the patients in the study was 40.0 years, an age usually associated with a poor outcome in IVF.

4. The CGH technique allows visualisation of numerical loss or gain in each of the 23 chromosome pairs of a cell, reflected in array patterns above or below a normal reference range. A numerical gain at chromosome 21, for example, ("trisomy 21") is consistent with risk of Down's syndrome.

5. Two polar bodies are formed as an oocyte reaches maturity. They each contain by-products from the maturation process. The first polar body is extruded at the time of ovulation (when mature), and the second at fertilisation.

ESHRE is the world's leading professional society in reproductive science and medicine, with almost 6000 members throughout the world.

More information on this press release and further comment from Professor Gianaroli is available from ESHRE's central office

Hanna Hanssen | EurekAlert!
Further information:
http://www.eshre.eu

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

Information integration and artificial intelligence for better diagnosis and therapy decisions

24.05.2017 | Information Technology

CRTD receives 1.56 Mill. Euro BMBF-funding for retinal disease research

24.05.2017 | Awards Funding

VideoLinks
B2B-VideoLinks
More VideoLinks >>>