Navigation Links
Detecting fetal chromosomal defects without risk
Date:5/6/2014

Chromosomal abnormalities that result in birth defects and genetic disorders like Down syndrome remain a significant health burden in the United States and throughout the world, with some current prenatal screening procedures invasive and a potential risk to mother and unborn child.

In a paper published online this week in the Early Edition of PNAS, a team of scientists at the University of California, San Diego School of Medicine and in China describe a new benchtop semiconductor sequencing procedure and newly developed bioinformatics software tools that are fast, accurate, portable, less expensive and can be completed without harm to mother or fetus.

"We believe this approach could become the standard of care for screening of prenatal chromosomal abnormalities," said Kang Zhang, MD, PhD, professor of ophthalmology, founding director of the Institute for Genomic Medicine at UC San Diego and a staff physician at the San Diego VA Healthcare System.

The incidence of chromosomal abnormalities in numbers or structure is one in 160 live births in the United States, higher in other countries. In China, for example, the rate is one in 60 live births. The effects of these abnormalities, known as aneuploidies, can be severe, from developmental delays and neurological disorders to infertility and death. The incidence rate rises with maternal age, most notably after age 35.

Current diagnoses of fetal aneuploidies often rely upon invasive tests that sample amniotic fluid or placental tissues for fetal DNA that can then be analyzed using a variety of complex and expensive methods, including full karyotyping in which the entire set of chromosomes is viewed microscopically. While highly reliable, these invasive tests may cause infections in the pregnant woman and pose as much as a 1 percent risk of miscarriage and fetal loss. Results are not available for one to two weeks, extending anxiety for families waiting for information.

The new method relies upon massively parallel sequencing of cell-free fetal DNA using a benchtop semiconductor sequencing platform (SSP) called an Ion Torrent sequencer developed by Life Technologies. Cell-free fetal DNA is genetic material from the fetus that circulates naturally and freely in the mother's bloodstream. It can be obtained through an ordinary blood draw, with SSP analysis achieved in less than four days.

To assess the SSP method, researchers tested 2,275 pregnant women. More than 500 participated in a retrospective analysis, undergoing full karyotyping to establish known chromosomal abnormalities followed by SSP testing. The remainder participated in a prospective study without prior karyotyping, and SSP testing results were then compared to karyotyping results. The sequencing and automated bioinformatics analyses were performed at iGenomics in Guangzhou, China.

"We used the retrospective study to establish the method and the prospective study to validate it," said Zhang.

In the retrospective study, the researchers found that SSP detected multiple types of chromosomal abnormality with virtually 100 percent sensitivity and specificity compared to full karyotyping.

"To our knowledge, this is the first large-scale clinical study to systematically identify chromosomal aneuploidies based on cell-free fetal DNA using SSP," said Zhang. "It provides an effective strategy for large-scale, noninvasive screenings in a clinical setting. It can be done in hospitals and outpatient clinics, more quickly and cheaply."


'/>"/>

Contact: Scott LaFee
slafee@ucsd.edu
619-543-6163
University of California - San Diego
Source:Eurekalert

Related biology news :

1. New ultrasound device may add in detecting risk for heart attack, stroke
2. A new approach to detecting changes in GM foods
3. Closer to detecting preeclampsia
4. American Chemical Society podcast: Detecting radioactive material in nuclear waste water
5. Finnish researchers develop quick test kit for detecting phenolic compounds in drinking water
6. Detecting mirror molecules
7. Texas Biomed reports faster, more economical method for detecting bioterror threats
8. By detecting smallest virus, researchers open possibilities for early disease detection
9. Detecting breast cancers fingerprint in a droplet of blood
10. DNA test better than standard screens in identifying fetal chromosome abnormalities
11. Cannabis during pregnancy endangers fetal brain development
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/18/2017)... a global expert in SoC-based imaging and computing solutions, has developed ... the company,s hybrid codec technology. A demonstration utilizing TeraFaces ® , ... showcased during the upcoming Medtec Japan at Tokyo Big Sight April ... Vegas Convention Center April 24-27. ... Click here for an image of the M820 ...
(Date:4/11/2017)... April 11, 2017 Crossmatch®, a globally-recognized ... solutions, today announced that it has been awarded ... Projects Activity (IARPA) to develop next-generation Presentation Attack ... "Innovation has been a driving force within ... will allow us to innovate and develop new ...
(Date:4/6/2017)... -- Forecasts by Product Type (EAC), Biometrics, ... (Transportation & Logistics, Government & Public Sector, Utilities / ... Facility, Nuclear Power), Industrial, Retail, Business Organisation (BFSI), Hospitality ... looking for a definitive report on the $27.9bn Access ... ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... A new ... rates in frozen and fresh in vitro fertilization (IVF) transfer cycles. ... to IVF success. , After comparing the results from the fresh and frozen ...
(Date:10/10/2017)... ... 10, 2017 , ... For the second time in three ... Mentoring Award. Representatives of the FirstHand program travelled to Washington, D.C. Tuesday, October ... US2020’s mission is to change the trajectory of STEM education in America by ...
(Date:10/10/2017)... ... October 10, 2017 , ... USDM Life Sciences , ... life sciences and healthcare industries, announces a presentation by Subbu Viswanathan and Jennifer ... “Automating GxP Validation for Agile Cloud Platforms,” will present a revolutionary approach to ...
(Date:10/9/2017)... Charlotte, N.C. (PRWEB) , ... October 09, 2017 , ... ... Purple announced Dr. Christopher Stubbs, a professor in Harvard University’s Departments of Physics and ... Dr. Stubbs was a member of the winning team for the 2015 Breakthrough Prize ...
Breaking Biology Technology: