Rare Genetic Disorder in Ecuador Offers Cancer Prevention Clues

In the Ecuadorean town of Piñas, nestled among the southern Andes, lives an unusual concentration of people with Laron syndrome—a rare genetic condition that stops the body from growing beyond about 1.2 meters. Among them are twin sisters María Luísa Romero and María del Cisne, now 40, who have lived their entire lives with the condition. What researchers have discovered in studying them and others like them may reshape how scientists think about cancer prevention.

Laron syndrome occurs when a genetic mutation prevents the body from using growth hormone effectively. The mutation blocks the production of a hormone called Insulin-like Growth Factor 1, or IGF-1, which regulates cell growth. The condition is named after Israeli pediatrician Zvi Laron, who first identified it six decades ago. Globally, only about 840 people are known to have it, but Ecuador—particularly the provinces of El Oro and Loja—holds the majority of cases. Researchers believe the mutation originated in Indonesia thousands of years ago and spread westward through merchant routes, eventually reaching Sephardic Jewish communities whose members later migrated to the Americas and settled in isolated areas where intermarriage concentrated the genetic trait.

Over 22 years, Dr. Jaime Guevara, an endocrinologist who has studied the condition for four decades, led a major research effort comparing about 100 people with Laron syndrome to roughly 1,600 relatives of normal height living in the same villages. The findings were striking. Among those with Laron syndrome, researchers found zero cases of diabetes and only one case of non-fatal cancer. In the control group of normal-height villagers, 5 percent developed diabetes and 17 percent developed cancer. Since both groups shared the same environment and similar genetic backgrounds, researchers concluded that the difference stemmed from the activity—or rather, the absence—of growth hormone and IGF-1.

The theory emerging from this work is that IGF-1 normally prevents cancer cells from undergoing apoptosis, the process by which damaged cells die. People with Laron syndrome, lacking sufficient IGF-1, may therefore have a natural defense against cancer development. Dr. Valter Longo, a specialist in aging from the University of Southern California, joined Guevara's team to explore this mechanism further. The hope is that scientists could eventually replicate this protective effect through medication or dietary intervention, offering cancer prevention to people without the syndrome. "It would be a great contribution from this wonderful community to the world," Guevara told researchers.

But the lived reality of Laron syndrome remains difficult. The twins describe the challenges of growing up visibly different in a society unprepared for their presence. When they left Piñas to study elsewhere, they faced constant stares and pointed fingers. "They had never seen short persons like us there, so everyone looked at us strangely," María Luísa recalls. Living among others with the same condition has provided crucial emotional support. "We can tell each other about the things that happen to us, the good and the bad, because we definitely share many of the challenges we have to face every day," María del Cisne explains. The twins have found acceptance in their adulthood, though they wonder what their lives might have been had treatment been available in their youth.

That treatment exists but remains largely inaccessible. Increlex, a drug developed 15 years ago, can increase height if given during childhood growth spurts between ages two and eighteen. But a single bottle costs more than $800, and a child requires at least three bottles monthly—$2,400 per month—since only one pharmaceutical company produces it. Mayra Loaiza, who also lives in Piñas, has been waiting six months for her two-year-old daughter Camila to receive her first dose. The delay weighs heavily. "I want my daughter to have as normal a life as possible. I don't want her to be discriminated against because of her size," Mayra says. For the twins, who missed the treatment window entirely, the regret lingers even as they have made peace with themselves. "The treatment would have saved us a lot of heartache," María Luísa reflects.

Research continues on multiple fronts. Prof. Laron, now based at Tel Aviv University, has documented 70 Israeli patients over 58 years and observed similar cancer protection. A comprehensive research paper cataloging all known cases of the mutation identified between 1966 and 2025 is set for publication in July. Yet even as the science advances, Prof. Laron acknowledges mysteries remain. He notes that some Laron patients who received IGF-1 treatments as children to promote growth also showed no cancer development, suggesting the protective mechanism involves more than IGF-1 levels alone. Ongoing studies in mice and pigs may eventually unlock the full explanation. For now, the people of Piñas continue to live with their condition, aware that their bodies may hold secrets that could one day benefit millions.