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The study was published in the journal Proceedings of the National Academy of Sciences of the United States of America.
Prof Allan Herbison, director of the Centre for Neuroendocrinology in Otago's department of physiology, said the study was also a ``real career highlight''.
It was ``fantastic'' that 10 years of basic Otago research was helping develop potential new therapies for the one-third of infertile people whose problems resulted from aspects of brain control of fertility, he said.
It was little known that the brain controlled fertility, by first controlling the pituitary gland, which in turn controlled the ovaries in females and testes in males, he said.
The brain did this by generating pulses of hormone secretion in the blood about once an hour, in males and females, which told the ovary or testis what to do.
Since pulsatile hormone secretion was discovered more than 40 years ago, a ``fundamental problem'' had remained in trying to understand how the pulses were generated.
Prof Herbison and principal co-authors Dr Jenny Clarkson and Dr Su Young Han have identified a group of about 2000 kisspeptin neurons in the brain's hypothalamus that synchronise their activity to generate the hormonal pulse.
Kisspeptins are a family of proteins that are essential for fertility.
This discovery had important implications for better understanding and manipulating fertility.
Women with polycystic ovarian syndrome, which affects about 5% of all reproductively aged women, had pulses that occurred too fast, often leaving them infertile.
Other women, who were not generating pulses of hormone or in whom the pulses were too slow, had a condition called hypothalamic amenorrhoea, which also caused infertility.
British Neuroscience Association president Prof Stafford Lightman said identifying the site of the brain's pulse generator that controlled essential reproductive hormones had been a ``holy grail'' of neuroendocrinologists for the past 40 years.
The Otago study opened the way to develop ``new therapeutic strategies'', Prof Lightman said.