Mechanism of maternal age effect on oocytes is questioned

Mechanism of maternal age effect on oocytes is questioned
New research suggests that the "production-line model" is not the basis for the maternal-age effect on trisomy, according to research published in the July 3 issue of the American Journal of Human Genetics.

(HealthDay)—New research suggests that the "production-line model" is not the basis for the maternal-age effect on trisomy, according to research published in the July 3 issue of the American Journal of Human Genetics.

Ross Rowsey, of Washington State University in Pullman, and colleagues conducted molecular cytogenetic studies using 191 samples of second-trimester human fetal ovaries to examine the number and distribution of crossover-associated proteins in more than 8,000 prophase-stage oocytes. The researchers looked for evidence supporting or refuting a key component of the "production-line model," stating that the first oocytes to enter have more recombination events (crossovers) than those that enter meiosis later in fetal life.

The researchers found that, although recombination levels varied among fetal samples, there was no evidence that they differ for oocytes entering meiosis early in fetal life compared with those that enter meiosis late in fetal life.

"Thus, our data provide a direct test of the second tenet of the production-line model and suggest that it does not provide a plausible explanation for the human maternal-age effect, meaning that—45 years after its introduction—we can finally conclude that the production-line model is not the basis for the maternal-age effect on trisomy," the authors write.

More information: Abstract
Full Text (subscription or payment may be required)

add to favorites email to friend print save as pdf

Related Stories

Do ovaries continue to produce eggs during adulthood?

Jul 26, 2012

A compelling new genetic study tracing the origins of immature egg cells, or 'oocytes', from the embryonic period throughout adulthood adds new information to a growing controversy. The notion of a "biological clock" in women ...

Recommended for you

Gamers helping in Ebola research

9 hours ago

Months before the recent Ebola outbreak erupted in Western Africa, killing more than a thousand people, scientists at the University of Washington's Institute for Protein Design were looking for a way to stop the deadly virus.

Carcinogenic role of a protein in liver decoded

12 hours ago

The human protein EGFR controls cell growth. It has mutated in case of many cancer cells or exists in excessive numbers. For this reason it serves as a point of attack for target-oriented therapies. A study ...

A new way to diagnose malaria, using magnetic fields

Aug 31, 2014

Over the past several decades, malaria diagnosis has changed very little. After taking a blood sample from a patient, a technician smears the blood across a glass slide, stains it with a special dye, and ...

User comments