We all know that sooner or later it will come, but when and how no one is able to predict it for sure. At least for now. We are talking about menopause: the world average sets a range of six years, between 47 and 52, but for one in 25 women it happens even earlier, already around 40. What is called precose menopause. International researchers from the Qimr Berghofer Medical Research Institute in Brisbane, Australia, went to analyze the genetic data of over 200,000 women of European origin – then compared and validated with those of another 100,000 of Asian origin – who had the cycle. even up to the age of 60 and identified 290 genetic variants associated with age at menopause.
Perimenopause, because women don’t know it
by Valentina Arcovio
We are talking about the largest genomic study conducted on the subject so far: it was published in Nature and unveils a number of biological mechanisms that regulate the reproductive lifespan of women that could be used as novel therapeutic approaches in the future.
The authors – John Perry, Anna Murray, Eva Hoffmann and Katherine Ruth – they analyzed something like 13.1 million genetic variants: a very long job, looking for those elements that unite women who have had a cycle longer than others and thus identified 290 “determinants” of ovarian aging associated with menopause delayed. It was found that “a wide range of DNA damage response genes are associated with age at natural menopause, operating throughout a woman’s lifespan to control ovarian function,” suggesting “a causal relationship between menopause delayed and improved bone health, as well as a reduced likelihood of developing type 2 diabetes ”. The bad news is that “delayed menopause has also been associated with an increased risk of hormone-sensitive cancers.”
Mothers over 45, unlikely and dangerous
by Elvira Naselli
“Reproductive longevity is essential for fertility and the influence it has on female aging, but so far the insights into biological mechanisms and possible treatments have been limited. The 290 genetic determinants of ovarian aging we have identified, of which six are on the X chromosome that, to our knowledge, has never previously been tested in large-scale studies – write researchers coordinated by Dr Perry, a geneticist at the University of Cambridge. discoverer of the “puberty clock” -, they act throughout the life to model the ovarian reserve and its rate of exhaustion. A better understanding of how and when these molecular processes affect the establishment and decline of the ovarian reserve will inform future strategies on how to preserve fertility and treat infertility. “
The timing of reproduction
Over the past 150 years, life expectancy in developed countries has risen from 45 to 85 years, but the timing of the reproductive age has remained constant. “The genetic integrity of oocytes decreases with advancing age and natural fertility ceases already 10 years before menopause – continue the authors -. More women are choosing to delay pregnancy to a later age, resulting in the increase in assisted reproduction techniques: the preservation of oocytes and ovarian tissue can prolong fertility, but it is invasive and there is only a 6 , 5% chance of getting pregnant with a thawed mature egg ”. Previous analyzes have highlighted the involvement of DNA repair in the regulation of ovarian aging. Now “our findings support a much wider range of genetic damage and metabolic signaling, such as the DNA Damage Response checkpoint kinase and the role of Chek1 and Chek2 in double strand breakage.”
It’s not just a question of genes
“The fascination of a future in which women can extend their reproductive age will once again focus on balancing risks and benefits, as is the case now for the use of hormone replacement therapy – comments the doctor. Krina Zondervan of the University of Oxford, not involved in the research -. Certainly colleagues have paved the way for more detailed studies that could lead women to be able to predict their reproductive age and consider options to lengthen it. Being able to predict when it will occur would give women and their partners more flexibility in choosing when to have a child. This knowledge could also be particularly useful for women at high risk of premature menopause. Let us remember, however, that the age of natural menopause is determined by a complex interaction of not only genetic factors, such as poor infant nutrition, smoking and being overweight “. And this could make it more difficult not only to find an effective cure for all of them, but also to determine exactly the “due date” of our fertility.
.