Rare form of dwarfism could be the key to a longer life, scientists claim

By William On Apr 30, 2024

A rare form of dwarfism has been found to protect individuals against cancer and diabetes, suggesting the gene could hold the key to a longer life.

People with the condition are known as Laron syndrome and are around four feet tall because their bodies cannot use their own growth hormone produced in the brain – but they have an average lifespan of people without the disorder.

Scientists who followed a group of adults with Laron syndrome for nearly two decades have discovered how their rare condition can be a gift, protecting them from age-related diseases – and potentially paving the way for anti-aging treatments.

In the latest study among this group, a team of scientists from California and Ecuador found that people with Laron syndrome have lower blood sugar levels, insulin resistance and blood pressure compared to their relatives who do not have the condition.

Doctors Jaime Guevara-Aguirre (back left) and Valter Longo (back right), pictured with some participants in the Laron study at the USC Leonard Davis School of Gerontology in Los Angeles. The two researchers have been following individuals with Laron syndrome for years to find out what benefits their rare genetic syndrome offers them.

Ecuadorians Maritza Valarezo (right) and her sister Lugartda (left) both have Laron syndrome. There are only about 400 to 500 people worldwide known to have the rare genetic condition.

The study participants were also found to have smaller hearts than their relatives, lower carotid artery thickness and less arterial plaque – the substance that can narrow blood vessels and lead to heart attack, heart failure or blood clots.

Doctors first identified Laron syndrome in adults with dwarfism living in a remote corner of Ecuador. It is also known as growth hormone receptor deficiency, or GHRD for short.

Individuals with Laron syndrome typically have high levels of growth hormone, but their genetic mutation prevents their body from producing the target for the hormone.

This target, called a receptor, is like a lock.

When co-lead study author Dr. Jaime Guevara-Aguirre first started studying Laron syndrome, he was surprised that the condition seemed to protect against cancer.

After all, higher levels of growth hormone are usually linked to cancer – and this relationship has proven reliable in most people.

Guevara-Aguirre, an endocrinologist at Universidad San Francisco de Quito, Ecuador, has been studying Laron dwarfism for more than two decades and previously told DailyMail.com: ‘We have found that people with Laron simply don’t get cancer.

“Cancer can be detected in normal-sized relatives, but never in my patients – not a single case,” he said.

Most people with Laron syndrome come from Ecuador, where the average heights for men and women – five feet, six inches and five feet and a half inches – are among the shortest in the world.

For this reason, these individuals tend not to think of themselves as particularly small.

Women with Laron average about four feet tall, and men tend to be about four feet tall.

But what many of them do realize is that they have a special biological gift.

‘Since my teenage years I saw my height as (an opportunity) to develop; the problem of growth is part of my personality’, Nathaly Paola Castro Torres told CNN in Spanish.

“I’m also very lucky because in reality my body protects me a lot from diseases that other people have every day,” she added. “This height is not only a limitation, but also a blessing.”

Insulin-like growth factor 1 (IGF-1) is produced in the liver. In people with typical genetics (left), growth hormone from the pituitary gland in the brain tells the liver to produce more IGF-1, which can contribute to aging and age-related diseases. But in people with Laron syndrome (right), despite high levels of growth hormone, their livers produce much lower amounts of IGF-1, protecting them from heart disease.

Maritza (left) and Lugartda Valarezo (right), in their kitchen in Quito, Ecuador, in 2014. The Valarezo sisters are patients of co-lead study author Jaime Guevara-Aguirre, who has been studying Laron syndrome for more than two decades.

Because of their resistance to chronic diseases, people with Laron syndrome have been the subject of great interest among doctors and scientists seeking treatments for age-related diseases.

“We have shown in studies that people with Laron have a very low incidence of cancer, diabetes and cognitive decline,” said co-lead study author Dr. Valter Longo, professor of gerontology at the University of Southern California.

‘Brain scans have shown that they have a more youthful brain, the equivalent of someone 20 years younger. I have not seen a case of Alzheimer’s in this population yet.’

Some even claim that studying these patients will lead to a cure for cancer and diabetes

“It doesn’t mean they’re immune to these diseases, but people with Laron syndrome certainly seem to be very protected,” Longo said of the latest research into heart health. “That’s how powerful this mutation appears to be.”

Based on the new study, the key appears to be a hormone called insulin-like growth factor 1 (IGF-1).

This chemical is mainly produced in the liver.

In people with typical genetics, growth hormone from the brain’s pituitary gland instructs the liver to produce more IGF-1, which supports normal wound healing and other metabolic processes.

However, high levels of IGF-1 may contribute to aging and age-related diseases.

In people with Laron syndrome, despite high levels of growth hormone, their liver produces much lower amounts of IGF-1, which appears to protect them against heart disease.

In mice, a deficiency of IGF-1 has led to heart disease, so the results of the new study were somewhat unexpected.

Researchers also said that the low levels of IGF-1 in the blood of people with Laron syndrome contribute to a reduced risk of cancer and diabetes, but more research is needed to figure out the details of that link.

‘Although the population tested is small, these human data, together with studies in mice and other organisms, provide valuable insights into the health effects of growth hormone receptor deficiency and suggest that medications or dietary interventions that produce similar effects may reduce disease incidence and possibly extend lifespan. can extend. ,’Longo said.

The study was published in the magazine Med.

According to scientists, the accidental discovery could lead to a cure for cancer

In the late 1950s, Israeli endocrinologist Zvi Laron began studying patients, some with childhood diabetes and others with growth and sexual development disorders.

His first patients included three young siblings – two boys and a girl – all with severe growth retardation. They were all obese, had thin hair, a pronounced forehead and a collapsed nasal bridge, and their grandparents were cousins.

Laron assumed that they had a severe growth hormone deficiency, but several years later, after new blood tests were developed, it turned out that the growth hormone levels were abnormal – they were extremely high.

By the mid-1960s he had identified another twenty such people. He reasoned that they either had faulty hormones or that something was wrong with the cells that respond to those hormones.

Every cell in the body contains receptors, which act as little locks for hormones, Discover Magazine reports.

When a hormone finds a suitable slot, it binds to the receptor and prompts the cell to do something, such as grow or divide.

But while studying his test subjects’ cells, Laron discovered that normal growth hormone could not bind to its receptor, indicating that they were damaged.

In 1984, he published a paper showing that the short stature of people with Laron syndrome results from their inability to respond to growth hormone, no matter how much they float around.