Recent research uncovers a fascinating link between Neanderthal DNA and a serious brain condition called Chiari malformation type I. This disorder, which affects about 1 in 100 people, occurs when the lower part of the brain, known as the cerebellum, bulges through the skull. Symptoms can range from mild headaches to severe pain and even life-threatening complications.
In mild cases, muscle relaxants may alleviate the symptoms. For severe cases, surgery might be necessary to create more space for the brain. According to Mark Collard, a paleoanthropologist at Simon Fraser University, understanding this condition better could significantly improve treatment outcomes.
Chiari malformation was first described in the 1800s by Austrian pathologist Hans Chiari. Initially thought to affect only 1 in 1,000 people, recent imaging studies suggest the real number could be much higher. Many cases go undiagnosed because they don’t show major symptoms.
What causes this condition? It arises when the occipital bone at the back of the skull is too small, leading to pressure on the brain. The exact reason for this size mismatch is still unknown.
A 2013 study proposed that interbreeding with Neanderthals may have contributed to this and other modern ailments. Everyone with non-African ancestry has around 1.5% to 2% Neanderthal DNA, which may influence skull shape and size, potentially leading to disorders like Chiari malformation.
To delve deeper into this idea, researchers studied 3D CT scans of 103 people, with 46 having the disorder and 57 not. They found that the skull shapes of those with Chiari malformation resembled Neanderthal skulls more closely than those without the condition.
Kimberly Plomp from the University of the Philippines summarized the findings: “We may be closer to understanding what causes Chiari malformation type I.” However, she notes that this doesn’t confirm a direct link yet. Experts emphasize the need for further research to validate these findings and explore international data, particularly from Africa.
If it becomes clear that Neanderthal genes are connected to Chiari malformation type I, it could lead to new health practices. Screening for these genes in children might help identify those at higher risk, allowing for early monitoring and intervention.
This study appears in the journal Evolution, Medicine, and Public Health, marking a step toward better understanding and managing this complex health issue.
