Funks SwabbieIn the high mountains of northwestern Colombia, there is a village called Yarumal where everyone is related but didn’t know. At first glance, it looks like any other Andean settlement. Beyond the modest houses and churches, people follow routines shaped by agriculture, family life, and faith. Nothing about Yarumal seems unusual to an outside visitor.
Yet this small community carries a remarkable story that remained hidden for centuries. Nearly all families in Yarumal share a common ancestor, although for much of the town’s history, no one realized it. The deep connection between its people came to light only when scientists arrived to investigate a strange pattern of illness. What followed revealed one of the most concentrated genetic lineages ever documented in a modern population.
This is the story of how a forgotten inheritance shaped a community, how a rare genetic mutation traveled silently through bloodlines, and how the truth of a shared past changed the way an entire village understood itself.
The first clues came long before anyone had the tools to interpret them. Families in Yarumal often whispered about a disease that appeared far too frequently among their neighbors. Elders would speak of relatives who lost their memory unusually early, sometimes in their forties or fifties. The affected individuals became confused, repeated conversations, misplaced tools, wandered at night, and eventually required constant care.
Locals gave the illness many names, yet few understood what it truly was. In reality, these cases were not random episodes of forgetfulness. They were expressions of the same inherited genetic mutation, silently carried through generations.
Still, no one imagined the pattern stretched across nearly every family tree. The people of Yarumal married, raised children, farmed the hillsides, and lived out their lives unaware of the deep connection linking them all.
The Arrival of Researchers
In the late twentieth century, neurologist Francisco Lopera of the University of Antioquia began documenting cases of early-onset memory loss in the region. His team kept detailed notes, tracing symptoms, speaking with families, and searching for patterns that might explain why so many individuals were affected.
Over time, they uncovered something extraordinary. Many of the patients were not simply neighbors; they were biologically connected, even when the families themselves had no awareness of a shared past. When researchers constructed genealogical maps of the village, the branches repeatedly converged on a single figure: a Spanish man who had settled in the region in the seventeenth century.
The scientists traced the origin of the mutation to this ancestor. With each generation, the mutation moved through marriages, births, and large family networks, eventually becoming one of the strongest known clusters of inherited early-onset Alzheimer’s disease on earth.
A Single Mutation With Enormous Reach
The mutation documented in Yarumal is now known as Presenilin-1 E280A, commonly referred to as the Paisa mutation. It causes early-onset Alzheimer’s, an aggressive form of the disease that can strike decades earlier than the more common age-related type.
One copy of the faulty gene is enough to produce the illness. Because families in Yarumal had large numbers of children and little historical contact with outside populations, the mutation circulated widely.
When researchers mapped the connections, they found that a striking share of the town’s population descended from the same ancestor. In other words, they were not merely neighbors ― they were distant cousins. Many had grown up together, attended the same school, worked in the same fields, and shared celebrations without ever learning that their lineage intertwined centuries earlier.
The discovery reshaped how the village understood its own history.
Life in the Village Before the Truth Emerged
Before scientific research arrived, the people of Yarumal accepted the illness as a tragic but familiar reality. Entire generations watched parents or siblings fade into the disease, often without any medical explanation. Living with it became a part of local identity.
Children grew up knowing that an aunt or grandfather had lost their memory early. Families cared for their elders quietly, relying on community support. People held to the hope that their own lives might escape the pattern.
Yet the mutation worked silently through the bloodlines. Those who inherited it would develop symptoms with alarming predictability.
Even so, most did not know that they were connected to almost every other household in the region. The ties between families were buried deep enough that only scientific mapping could reveal them.
When Lopera’s team presented their findings, the people of Yarumal learned that many of them shared a single ancestor who had carried the original mutation from Spain. His arrival in the region marked the beginning of a lineage that became interwoven with the town’s identity.
The revelation had profound effects. Some residents struggled with the knowledge that they carried a genetic burden inherited from an unknown ancestor. Others felt relief in finally understanding why their family had suffered so much loss.
For many, the discovery also strengthened community bonds. Knowing they were connected through a shared past, townspeople began to speak more openly about the illness. Families supported one another, and caregivers built networks to share advice and resources. What had once been a private source of sorrow became a collective experience.
The story also brought Yarumal to global attention. Scientists, journalists, and documentary crews traveled into the mountains to study the village and understand how such a rare mutation could shape an entire community.
The concentration of the mutation in Yarumal turned the community into a key site for Alzheimer’s research. Because the disease appears predictably and early, scientists can observe its progression from the first biological changes to the earliest symptoms.
International teams have collaborated with local families to study the mutation, track cognitive changes, and search for treatments. Some residents travel to medical facilities to undergo tests, brain imaging, and experimental therapies. Others participate in long-term observational studies that may help uncover clues about how Alzheimer’s begins.
In several cases, discoveries made in Yarumal led to new insights into how the disease forms in the brain. Research into the mutation also opened the door to preventive trials, aiming to slow or delay the onset of symptoms.
The village that once held its story quietly now contributes to scientific knowledge that may help millions.
The discovery that nearly all families in Yarumal share a common ancestor forced the village to re-examine its understanding of identity. People found themselves connected not only by geography or culture but by blood. Some embraced this as a sign of unity. Others viewed it as a reminder of how little one knows about the past.
Several residents began recording family histories, speaking with elders, and piecing together forgotten branches of family trees. Oral traditions resurfaced. Stories about early settlers and long-lost relatives were shared at gatherings. In time, the community created a fuller picture of how their families had grown together.
The village learned that inheritance is not merely a passage of traits from parent to child. It is memory, shared experience, and the ties that hold a community together. For Yarumal, the discovery transformed a medical mystery into a story of human connection.
Today, the people of Yarumal continue their daily lives while balancing tradition with medical progress. Some carry the mutation knowingly. Others choose to be tested. Many prefer not to learn their genetic status.
Regardless of their choice, the community remains bound by shared history. Children still play in the streets, market stalls still open each morning, and the mountains stand unchanged above the town.
What has changed is the village’s understanding of itself. Once unaware that they were connected through bloodlines reaching back centuries, the people of Yarumal now carry that knowledge as part of their identity.
Funks Swabbie
