Scientists discover a gene in the brain that controls sexual desire in men – and it could be used to target treatments for male sex addiction
- Enzyme called aromatase converts testosterone to oestrogen in the brain of men
- Researchers have also identified the single gene which creates this enzyme
- Process of converting testosterone to oestrogen is what creates male sex drive
A gene has been discovered in the brain that regulates male sexual desire, paving the way for new treatments for sex addiction and dysfunction.
The gene controls an enzyme, called aromatase, which is responsible for converting testosterone into oestrogen in the brain, which drives male sexual activity.
Oestrogen is commonly known as the female sex hormone, but it is needed in high levels to drive libido, and is essential for erectile function.
Without oestrogen being made from testosterone, a man’s sex drive plummets.
Researchers from Northwestern University found that aromatase is produced by a single gene, called Cyp19a1, opening up potential routes to target the enzyme.
By successfully isolating the gene responsible for creating the enzyme, researchers hope to develop drugs to treat male sex addiction and low libido.
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A study from Northwestern University investigated the role of aromatase in the brain and found the enzyme converts testosterone into oestrogen. This process is key to mal esex drive (stock)
The role of aromatase in the brain has been the topic of lots of research, with scientists struggling to understand its purpose.
Discovering it converts testosterone into oestrogen, and the gene responsible for producing the enzyme, is a major breakthrough.
‘This is the first key finding to explain how testosterone stimulates sexual desire,’ said senior author Dr Serdar Bulun at Northwestern University.
‘For the first time, we demonstrated conclusively that the conversion of testosterone to estrogen in the brain is critical to maintain full sexual activity or desire in males. Aromatase drives that.’
Researchers removed the aromatase gene from the brain of male lab mice and put them in cages with a female mouse.
Subsequent sexual activity was slashed in half despite the rodents having higher than normal levels of testosterone.
The inability to convert the hormone from testosterone to oestrogen had a clear impact on sexual desire.
Converting testosterone into oestrogen is needed in high levels to drive libido and is essential for erectile function. Without it, the sex drive of a man plummets. Researchers also found aromatase is produced by a single gene, called Cyp19a1 (stock)
‘Male mice partially lost interest in sex,’ said co-author Dr. Hong Zhao.
‘Aromatase is the key enzyme for estrogen production. Estrogen has functions in males and females.
‘Testosterone has to be converted to estrogen to drive sexual desire in males.’
Aromatase deficiency is very rare in humans, but there have been documented cases. These men suffer from chronically elevated testosterone levels.
When undergoing with oestrogen therapy, the aromatase-deficient men reported significant improvements in the frequency of sexual activity.
However, the knoc-on implications of this latest study reach far beyond aromatase-deficient men and could help modulate sexual desire in large groups of men.
For example, many men suffer from low sexual desire, clinically known as hypoactive sexual desire disorder.
It can be brought on by some medications, including a group of antidepressants known as SSRIs.
If drugs can be created which target the aromatase enzyme in the brain then it could lead to heightened sexual desire, the researchers say.
At the other end of the scale, it could also be used to tackle compulsive sexual desire.
Existing treatments have serious side-effects but new selective drugs could avoid this.
The full findings are published in the journal Endocrinology.