According to a new study, researchers have found a ‘weak spot’ within the brain that develops slowly since adolescence, deteriorates early during aging, and can be linked to dementia. This study indicates three factors most likely to lead to the degradation of the brain region. For instance, diabetes, alcohol consumption, and nitrogen dioxide from traffic-related air pollution might be the primary reasons among many. Unique to this new research were two mutations of a lesser-studied genome and an enigmatic blood group called the XG antigen system. Â
Even though this study focuses mainly on modifiable factors, the authors feel that including potential genetic influences provides a clear picture of health within individuals. Brain scans of 39,676 UK biobank volunteers were analyzed. They were considered healthier than the general population. Among them, only a few have received a diagnosis of dementia, and the participants range from 44 to 83 years of age. They measured the effects of 161 elastic and a few other genetic factors. Among those, seven changes in the genome affect this ‘weak spot.’ Some of them are related to Parkinson’s disease, increased cardiovascular death, and schizophrenia. Â
A resident physician at George Washington University describes this weak spot in the brain as the network that develops last but is the first to degrade with age. The research identifies the brain regions that first decrease in Alzheimer’s, known as higher-order brain regions, including the prefrontal cortex, parietal cortex, and temporal cortex. Since these regions are associated with long-term memory and attention, they deteriorate with individual age or diseases like Alzheimer’s.  Â
The research team has closely seen the factors that influence the degeneration of these specific fragile brain regions. The main goal was to study what makes these brain regions degrade faster to help preserve brain health. The authors say that the research of X chromosomes revealed their most robust genetic findings within a peculiar region shared by both sex chromosomes. The XG antigen system is another gene that the researchers have analyzed to determine if it makes people susceptible to accelerated degeneration of their fragile brain system. They also discovered that individuals with a specific type of XG gene can be more affected by air pollution found in the air they breathe. This might be a significant factor contributing to damage within the brain’s fragile areas. Â
Doctors say there might be a link between environmental factors such as living in high-traffic areas or large cities with lots of pollution and increased risk of damage to fragile brain regions. Knowing a person’s genetic history allows healthcare providers and patients to take preventative measures and slow disease progression. Â
The authors pointed out another interesting, for now, unexplained finding: one of the novel genetic mutations they observed on the X chromosome was associated with early life and socioeconomic factors, including:Â Â
- Their number of siblings Â
- Whether they were breastfed as an infant Â
- Whether their mother smoked when pregnant Â
Journal Reference – Manuello, J., Min, J., McCarthy, P., Alfaro-Almagro, F., Lee, S., Smith, S., … Douaud, G. (2024). Genetic and modifiable risk factors affect brain regions vulnerable to ageing and disease.
Retrieved from https://www.nature.com/articles/s41467-024-46344-2Â
