Worms offer clues to declining fertility with age in women
Washington: New ways that may help maintain fertility in women who want to delay bearing a child may not be too far, as Princeton scientists have discovered genes responsible for controlling reproductive life span in worms.
They suggest that the find may help control genes regulating similar functions in humans too.
This work may someday allow women extend their reproduction and prevent maternal age-related birth defects.
"Could you give someone a drug or supplement when they are in their mid-30s that would keep their oocytes (immature egg cells) healthy? That`s the goal," said Coleen Murphy, lead author of the study.
She said that the approach would be similar to the regimen of daily allotments of folic acid taken by pregnant women to prevent the development of spina bifida in the foetus.
"We have found that there are many shared genes between worms and humans in terms of their reproductive qualities. So this isn`t just about worms and how they reproduce," said Murphy.
In the study, the researchers sought to understand what happens in roundworms, C elegans, as reproductive aging sets in.
They compared the activity levels of genes in normal roundworms with those of mutant roundworms that produce eggs until old age.
They found that a complex of genes important to human reproduction is more active in the second group.
These genes affect the ability of eggs to be fertilized, the proper segregation of chromosomes, DNA damage resistance and the very shape of the eggs.
In May, a research team led by Murphy reported it had found the first evidence that decreasing caloric intake and tweaking the activity of the hormone insulin in roundworms has an impact on cognitive function.
The findings have implications for the development of treatments that simultaneously help people livelonger and prevent the devastating losses in memory that so often occur with age.
C elegans are one of the simplest organisms that exist with a nervous system.
Scientists, as a result, have already mapped out every neuron in their bodies. They were the first multicellular organisms to have their genomes completely sequenced.
The bacteria-gobbling worms, which are about 1 millimeter long, live in temperate soil environments like gardens and compost heaps. Scientists like to study them because they are cheap to breed and can be frozen.
Though multicellular, the worms are simple enough to be studied in great detail. They are transparent, allowing scientists to watch their development in such detail that they have been able to track the fate of every cell produced at birth.
The study was published in the journal Cell.