According to a recent press release, scientists studying the Uniformed Services University of the Health Sciences’ (USU) The American Genome Center (TAGC) identified five genes which could play a role in whether people are more susceptible to developing dementia. In particular, the genes could cause either Lewy body dementia or dementia caused by Parkinson’s disease or Alzheimer’s disease. Researchers hope that these new insights could inform research and potential treatment options moving forward. Check out the full study findings published in Nature Genetics.

The Research

As explained in the abstract of the publication:

The genetic basis of Lewy body dementia (LBD) is not well understood. Here, we performed whole-genome sequencing in large cohorts of LBD cases and neurologically healthy controls to study the genetic architecture of this understudied form of dementia, and to generate a resource for the scientific community.

Researchers were interested in this line of treatment because of the heightened prevalence of dementia among veterans. However, researchers also questioned the relationship between Lewy body dementia, Alzheimer’s, and Parkinson’s. On what genetic level do these conditions relate? How do the Lewy bodies found in patients with Parkinson’s disease relate to those found in Lewy body dementia?

New Genes

In their study, researchers sequenced DNA from 2,981 patients with Lewy body dementia and 4,931 healthy individuals, all of whom had European ancestry. The second group acted as a control group. After their initial research, researchers discovered that BIN1, TMEM175, SNCA, APOE, and GBA genes often differed in patients with dementia than in the control group. While SNCA, APOE, and GBA have already been linked to dementia, including that caused by Alzheimer’s and Parkinson’s, in the past, this recent research was the first time the other two genes have been connected.

Next, researchers compared their research to DNA sequences from an additional 970 patients with dementia and 8,928 controls. Following this new sequencing, researchers determined the same genetic aberrations. As a result, researchers believe that patients with Alzheimer’s, Parkinson’s, and Lewy body dementia may have a similar genetic underpinning. This isn’t to say that the conditions are all the same; on a clinical and cellular level, Alzheimer’s, dementia, and Parkinson’s are different. However, the conditions may be similar on a genetic level.

Moving forward, researchers can use their new understanding of these genes for potential research and treatment options. In fact, the genes can stand as new therapeutic targets. Through this, researchers hope to create preventative treatment measures for both veterans and others with neurodegenerative conditions. Additionally, researchers uploaded their data to the dbGaP Portal to influence new research and allow for other scientists to access the data.

Lewy Body Dementia

According to the Lewy Body Dementia Association (LBDA):

Lewy body dementia (LBD) is the 2nd most common type of progressive dementia after Alzheimer’s disease. LBD is an umbrella term for two related diagnoses:

• A person with “dementia with Lewy bodies” will develop dementia and other LBD symptoms, one of which may be changes in movement like a tremor (parkinsonism).
• In the other form of LBD, people will present first with changes in movement leading to a Parkinson’s disease diagnosis; over time many will develop dementia years later. This is diagnosed as “Parkinson’s disease dementia”.

LBD affects over one million Americans. Risk factors include age (being 65+), being male, or having a family history of dementia or Parkinson’s. The name of the condition comes from Lewy bodies, or abnormal protein (alpha-synuclein) deposits in the brain. The National Institute on Aging (NIA) explains that:

In the healthy brain, alpha-synuclein plays a number of important roles in neurons (nerve cells) in the brain, especially at synapses, where brain cells communicate with each other. In Lewy body dementia, alpha-synuclein forms into clumps inside neurons, starting in areas of the brain that control aspects of memory and movement.

Symptoms include, but are not limited to:

• Forgetfulness
• Depression and apathy
• Difficulty with problem-solving or critical / analytical thinking
• Hallucinations
• Disorganized speech and conversation
• Changes in mood and behavior
• Excessive daytime sleepiness
• Confusion
• Muscle rigidity or stiffness

Learn more about Lewy body dementia.