Genetic secret to age of menopause: Scientists identify 300 genes that can predict when women will stop having periods – with one variant delaying the onset by 3.5 YEARS
- Scientists looked at genetic data gathered from 281,323 women in the UK
- They also designed mouse models to examine the effects of some of the genes
- Their analysis revealed 300 gene variants that influence the age of menopause
- Variation in Chek2 gene caused women to reach menopause 3.5 years later
- Findings could lead to improved infertility treatments in the future
Scientists have identified nearly 300 gene variations that influence women’s age of menopause.
The team from the University of Exeter found that these genetic variants are able to roughly predict the age at which some women will stop having periods, and identify those at risk of early menopause.
The findings could lead to improved infertility treatments in the future and increase the natural reproductive lifespan of women, according to the experts.
They could also lay the groundwork for future research on preventing certain types of cancer associated with hormones, such as ovarian and breast cancer, as well as type 2 diabetes.
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Scientists have identified nearly 300 gene variations that influence women’s age of menopause (stock image)
WHAT IS THE MENOPAUSE?
Menopause is defined as the changes a woman goes through just before and after she stops her periods and is no longer able to get pregnant naturally.
Some women go through this time with few, if any, symptoms, around 60 percent experience symptoms resulting in behavioral changes and one in four will suffer severely.
Common symptoms include hot flushes, night sweats, vaginal dryness leading to discomfort during sex, disrupted sleep, decreased sex drive, problems with memory and concentration and mood swings.
Menopause happens when your ovaries stop producing as much of the hormone oestrogen and no longer release an egg each month.
In the UK, the average age for a woman to reach the menopause is 51, according to the NHS.
Menopause is defined as the changes a woman goes through just before and after she stops her periods and is no longer able to get pregnant naturally.
Study co-author Dr Katherine Ruth, of the University of Exeter, said: ‘We hope our work will help provide new possibilities to help women plan for the future.
‘By finding many more of the genetic causes of variability in the timing of menopause, we have shown that we can start to predict which women might have earlier menopause and therefore struggle to get pregnant naturally.
‘And because we are born with our genetic variations, we could offer this advice to young women.’
For the study, the researchers looked at genetic data gathered from 201,323 women of European ancestry and an additional 80,000 women of East Asian ancestry from the UK Biobank, which has health and genetic information on around half a million people, as well as 23andMe, a consumer DNA testing company.
They also designed mouse models to examine the effects of some of the genes on the reproductive lifespan of the rodents.
In mice, the researchers found two particular genes, Chek1 and Chek2, to affect fertility and reproductive lifespan.
The team found that inactivating Chek2 so that it no longer functions while over-expressing Chek1 to enhance its activity increased reproductive lifespan in mice by around 25 per cent.
Women who switch to a vegan diet rich in soy during menopause could reduce the number of hot flushes they experience by up to 84 per cent without using drugs.
This is the conclusion of a study by researchers led from the George Washington University following tests of the diet involving 38 women over 12 week period.
Not only did the average number of moderate-to-severe hot flushes fall from five to one per day on the diet, but they were totally eliminated in 59 per cent of subjects.
The tested diet featured no hormone medications or extracts, the team explained — but instead combined a low-fat plant-based diet with cooked soy beans.
Meanwhile, in women who naturally lack an active Chek2 gene, the scientists found they reach menopause on average 3.5 years later than women with a normally active gene.
Professor Eva Hoffmann, of the University of Copenhagen, who is also a co-author on the study, said their findings ‘provide potential new direction for therapeutic approaches that might seek to treat infertility, particularly, in IVF treatment’.
She said: ‘IVF relies on hormone stimulation of women.
‘We found that in one of our mouse models, Chek2, the female mice there had an improved response to hormone stimulation, which means that more eggs were obtained for actual IVF treatment.
‘There are, of course, a number of scientific questions and safety concerns that have to be addressed before this is attempted in humans.
‘But what our studies show is that it is possible that targeted short-term inhibition of these pathways during IVF treatment could help some women respond better.’
The researchers also examined certain health impacts of having an earlier or later menopause.
They found genetically that earlier menopause increased the risk of type 2 diabetes and was linked to poorer bone health and increased risk of fractures.
But they found earlier menopause to decrease the risk of some types of cancer, such as ovarian and breast cancer.
Dr Ruth added: ‘We found that earlier menopause was causally associated with a lower risk of hormone-sensitive cancers.
‘We think this is probably due to having a shorter lifetime exposure to high levels of sex hormones (which are at higher levels while a woman is still menstruating).’
WHY DO SOME SPECIES GO THROUGH MENOPAUSE?
Few animals are known to experience menopause, with most species reproducing until they die.
Alongside humans; killer whales, killer whales, short-finned pilot whales, beluga whales and narwhals have evolved the trait.
Typically, menopause is triggered when animals undergo hormonal changes that cause them to stop being able to reproduce.
Researchers suggest this biological ‘off-switch’ is useful in species who spend most of their lives looking after their descendants.
In killer whales, for example, both male and female offspring stay with their mothers for life, as well as grandchildren.
The mother is responsible for finding food, and if she kept having offspring her direct descendants would have to compete for resources.
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