New method could double success rate of in vitro fertilization
Study in Cell reveals a safe, low-cost process to detect genetic defects in egg cells
By Mary Beth O'Leary Posted on 19 December 2013
Infertility affects up to 15 percent of couples around the world, and in vitro fertilization (IVF) is one way to treat this common condition. A study published by Cell Press today in the journal Cell reveals a safe, accurate and low-cost method to select genetically normal embryos for the IVF procedure and thereby increase a couple's chance of producing a healthy child.
Through whole-genome sequencing of individual egg cells, the new method detects chromosomal abnormalities and DNA sequence variations associated with genetic disorders.
[pullquote align="right"]"We kill two birds with one stone: one set of deep sequencing analysis to avoid two types of genetic problems."[/pullquote]
"In this way, we kill two birds with one stone: one set of deep sequencing analysis to avoid two types of genetic problems," said study author Dr. Jie Qiao, Chief Physician and head of the Department of Obstetrics and Gynecology at Peking University Third Hospital in Beijing. "Theoretically, if this works perfectly, we will be able to double the success rate of test-tube baby technology from 30 percent to 60 percent or even more."
The IVF procedure involves joining a woman's egg and a man's sperm in a laboratory dish and then transferring embryos into the woman's womb. Various procedures are currently available to detect genetic defects in embryos prior to implantation, but these approaches are often invasive, requiring the removal of cells from the growing embryo, and do not simultaneously detect both chromosomal abnormalities and DNA sequence variations associated with genetic disorders.
Researchers have recently developed whole-genome sequencing methods to simultaneously detect both types of defects in single human sperm cells, but until now, an analogous approach had not been applied to egg cells, even though chromosomal abnormalities are much more common in egg cells than in sperm cells.
Clinical trial is beginning
In the new study, Dr. Sunney Xie of Peking and Harvard universities teamed up with Dr. Qiao and Dr. Fuchou Tang of Peking University to develop a method for sequencing the entire genomes of polar bodies — cells that arise as a byproduct of egg cell division and often die later on. Because polar bodies are dispensable for human embryonic development, they can be safely removed without harming the embryo.
"We are now starting a clinical trial based on this approach," Dr. Xie said. "If the clinical trial works, this technique could enormously increase the success rate of IVF, especially for older women or women who have had recurrent miscarriages."
Read the article
This article is freely available on the Cell Press website until the end of 2013:
Cell, Hou et al.: "Genome Analyses of Single Human Oocytes."[divider]
Elsevier Connect Contributor
Mary Beth O'Leary (@MaryBethPress) is Press Officer and Associate Media Relations Manager for Cell Press (@CellPressNews), based in Cambridge, Massachusetts. She began her career at Cell Press as an Senior Editorial Assistant for the journal Cell before transitioning into a role as Marketing/Publicity Coordinator. In December, she moved into her position as Press Officer for Cell Press's 29 journals. A graduate of the College of the Holy Cross in Worcester, Massachusetts, she studied literature and art history.