Genetic traits inherited from Neanderthals potentially linked to brain disorder causing abnormal skull protrusion
In a groundbreaking study, researchers have proposed a potential link between Neanderthal DNA and Chiari malformation type 1 (CM-I), a neurological disorder that affects the lower part of the cerebellum and can cause a range of symptoms from headaches and neck pain to severe cases that can be fatal.
Lead by Kimberly Plomp, an osteologist at the University of the Philippines Diliman, the study suggests that genes inherited from Neanderthals through ancient interbreeding may predispose some people to this condition.
Modern research indicates that CM-I affects up to about 1% of people today. Studies comparing skull shapes and genomes found that the presence of Neanderthal DNA correlates with cranial traits resembling a smaller occipital bone, which is linked to CM-I.
The hypothesis, supported by 3D modeling and shape analysis of both modern human and fossil skulls, suggests that the introgression of Neanderthal genes into Homo sapiens altered skull morphology in ways that increase the risk for Chiari malformation type 1.
Although the association is compelling, researchers emphasize that the causal mechanism needs further confirmation. They argue that clarifying this genetic and evolutionary causal chain could improve understanding, management, or treatment of CM-I in the future.
The study examined 3D CT scans of the skulls of 103 living people and compared them with eight fossil skulls of close relatives of modern humans, including Neanderthals, Homo heidelbergensis, Homo erectus and prehistoric Homo sapiens. All other fossil skulls examined were more similar to modern humans without the disorder.
Collard suggested that future work could analyze more skulls, especially fossil ones, and collect data from Africa. The study found that modern human skulls with Chiari malformation type 1 were more similar in shape to Neanderthal skulls than those without the malformation.
The scientists detailed their findings in the journal Evolution, Medicine, and Public Health on June 27. If the link between Neanderthal genes and Chiari malformation type 1 is confirmed, screening for such genes could be added to early childhood health assessments, potentially improving the lives of those affected by this condition.
- The study proposes that genes inherited from Neanderthals could predispose individuals to medical-conditions like Chiari malformation type 1, which is a neurological disorder that affects health-and-wellness.
- If the link between Neanderthal genes and Chiari malformation type 1 is confirmed, it could lead to the inclusion of screening for such genes in early childhood health assessments, potentially improving the lives of those affected by this neurological-disorder.
