A study of several families with Laron syndrome (LS) in Ecuador has opened up the possibility of developing a drug or diet that could mimic its beneficial effects, according to a report published in El País.
When a growth hormone is bound to its receptor, it triggers signaling that stimulates the growth and division of cells. It also produces another important growth-promoting hormone called insulin-like growth factor I (IGF-I).
While affected individuals are close to normal size at birth, they experience slow growth from early childhood. Adult males typically reach a height of 4 ft 10 in (1.5 m) and adult females 4 ft (1.2 m).
LS is an incredibly rare congenital disorder characterized by marked short statue. The condition results from the body's inability to use growth hormone. It is usually caused by inherited growth hormone receptor (GHR) mutations.
Besides being well below median height, those with LS display other malformations, including craniofacial abnormalities.
Laron syndrome can also induce low blood sugar levels in infancy, leading to hypoglycemia.
Furthermore, people with Laron syndrome are generally unresponsive to growth hormone therapy. However, there are drugs available that if administered before puberty can be effective.
Management and treatment of the condition aims at improving growth in children.
People with LS people also appear to be less inclined to develop diabetes mellitus type II.
Despite these raft of symptoms, evidence has suggested that people with Laron syndrome have a significantly reduced risk of developing a number of life-threatening medical conditions, including cancer.
Laron syndrome was discovered in 1966 by Israeli pediatric endocrinologist Zvi Laron. His pioneering research opened the way to the treatment of many cases of growth hormone disorders. Over the years, Laron has published several studies focused on how to replicate the cancer-protective effects he sees in patients afflicted by LS.
Laron syndrome is recessive. In other words, you have to inherit two mutated copies of the gene, one from the father and one from the mother, to suffer from it.
And studies suggest that the Laron mutation also has a protective effect against cardiovascular diseases.
Furthermore and despite demonstrating high levels of "bad" LDL cholesterol, they have far fewer arteriosclerosis plaques—the substance that causes arteries to narrow, blocking blood flow. This is according to the medical science journal Med.
It's quite possible for one person with the syndrome to have healthy children. Similarly, it is also possible for two people without the syndrome to carry the mutation and have children with LS.
Laron syndrome is caused by mutations in the GHR gene. This gene provides instructions for making a protein called the growth hormone receptor.
Hair that is thin and fragile is indicative of the condition, as are dental abnormalities.
Adults with Laron syndrome tend to develop obesity. This is due to changes in metabolism caused by insensitivity to growth hormone and the resulting shortage of insulin growth factor 1 (IGF-1).
Affected individuals have short limbs compared to the size of their torso, as well as small hands and feet.
Mutations in the GHR gene impair the receptor's ability to bind to growth hormones or to trigger signaling within cells. Researchers are working to determine how mutations in the GHR gene may protect people with Laron syndrome from developing diseases such as cancer and type 2 diabetes.
Endocrinologists working in isolated towns in the provinces of Loja and El Oro, in the south of Ecuador, have ascertained that in these communities, endogamy—the custom of marrying only within the limits of a local community, clan, or tribe—is commonplace. This custom has facilitated the spread of the syndrome.
It does appear that Laron's mutation protects against diseases related to aging.
Studies have showed that people affected by the syndrome produced less IGF-1, a protein essential for childhood growth but which in adults also promotes uncontrolled cancer cell proliferation.
Biochemists, meanwhile, are looking at diets that mimic fasting, which lower IGF-1 levels in circulated blood—the supposed cause of the beneficial effects observed in people with Laron.
Laron syndrome is a very rare condition. About 350 people have been diagnosed with the disorder worldwide. The largest single group of affected individuals (about 100 people) live in an area of southern Ecuador. The second largest group (69 individuals) live in Israel.
This includes treatment with daily subcutaneous injections of mecasermin (a recombinant human insulin-like growth factor-1) and recombinant human IGF-I.
A diet with adequate calorie intake is also important. Frequent feeding is necessary in order to avoid hypoglycemia.
There is no treatment that prevents the onset of Laron syndrome, nor is there a cure.
Back in Ecuador, researchers are trying to establish a large-scale diagnosis system that would allow the inhabitants of the communities affected to know if their partners are carriers of the mutation.
The long-term goal is to identify methods of transferring the health benefits of Laron syndrome to the general population.
Sources: (El País) (Med) (MedlinePlus) (National Institutes of Health) (ScienceDirect)
Laron syndrome (LS) is an extremely rare medical disorder characterized by short stature and other physical abnormalities. Yet those afflicted with LS appear to be immune to a range of life-threatening conditions, including cancer, diabetes, and cardiovascular disease. LS is so rare that just 350 known cases have been recorded globally. Interestingly, a disproportionate number of these live in Ecuador. And it's in this South American nation that researchers are working on ways to harness LS' beneficial health effects. So, what causes this uncommon condition, and why is a genetic mutation proving so effective against some of our most notorious illnesses?
Click through this gallery and learn more about this little-known medical anomaly.
What is Laron syndrome, and can it really protect us from cancer and diabetes?
This rare disorder has remarkable health benefits
HEALTH Medical science
Laron syndrome (LS) is an extremely rare medical disorder characterized by short stature and other physical abnormalities. Yet those afflicted with LS appear to be immune to a range of life-threatening conditions, including cancer, diabetes, and cardiovascular disease. LS is so rare that just 350 known cases have been recorded globally. Interestingly, a disproportionate number of these live in Ecuador. And it's in this South American nation that researchers are working on ways to harness LS' beneficial health effects. So, what causes this uncommon condition, and why is a genetic mutation proving so effective against some of our most notorious illnesses?
Click through this gallery and learn more about this little-known medical anomaly.