Medindia LOGIN REGISTER
Medindia
Advertisement

Link Between CHRNA7 Gene and Neuropsychiatric Disorders

by Hannah Joy on December 28, 2017 at 12:13 PM
Link Between CHRNA7 Gene and Neuropsychiatric Disorders

A new pluripotent stem cell technology helps understand patients with neuropsychiatric disorders who have either extra copies or missing copies of the CHRNA7 gene, reveals a new study.

"For several years we have been studying patients with these conditions in different ways and also worked with mouse models in my lab. In this study we used a new pluripotent stem cell technology to pose questions that could not be answered with the other approaches," said corresponding author Dr. Christian Schaaf, assistant professor of molecular and human genetics at Baylor College of Medicine and the Joan and Stanford Alexander Endowed Chair for Neuropsychiatric Genetics at Texas Children's Hospital.

Advertisement


Pluripotent stem cell technology helps better understand neuropsychiatric disorders

"Pluripotent stem cell technology has allowed us to study what happens inside human brain cells from patients that have either fewer or extra copies of the CHRNA7 gene," said first author Dr. Madelyn Gillentine, a recent Ph.D. graduate of the Schaaf Lab.
Advertisement

"In summary, we take skin biopsies from patients with these conditions, grow the cells in culture in the lab and reprogram them to become brain cells. Using this approach, we gained insights into the mechanisms of disease at the neuronal level, which were really surprising."

The CHRNA7 gene is translated into CHRNA7 proteins that form a channel on the cell membrane that allows calcium to enter the cells. By regulating calcium levels, the CHRNA7 gene plays an important role on how neurons communicate and function with each other.

"We would have predicted that, compared with neurons from normal individuals, neurons from patients with fewer copies of this gene would show decrease in calcium flux, and those from patients who have extra copies would have more calcium flux, because they have more copies of this gene and are making more of the protein," Schaaf said.

As expected, the researchers found that neurons with fewer copies of the gene show a reduction in calcium flux, almost half of what they see in control samples, which they expect will have functional consequences on neuronal functioning in those patients.

"On the other hand, we were very surprised when we saw that neurons with extra copies of the gene, instead of an increase, they also showed a decrease in calcium flux that was not as severe as the one in the neurons with fewer copies of the gene," Gillentine said.

These results provide insights into why the patients with fewer copies of the gene share clinical characteristics with the patients with extra copies of the gene, despite having opposite underlying genetic makeup. In both cases, the result of the genetic imbalance is a decrease in calcium flux in the neurons.

Clinically, while the patients with fewer copies present with moderate to severe cognitive impairment, high prevalence of autism and other neuropsychiatric problems, those with extra copies present with similar but less severe characteristics.

Opposite genetic imbalance results in similar biological effect mediated by different mechanisms

In the case of neurons with fewer copies of the gene, and therefore fewer CHRNA7 proteins to form calcium channels, the researchers propose that the reduction in calcium flux in the cells results from having fewer calcium channels.

"For the neurons with extra copies of the gene, we found that having extra copies of the gene results in more CHRNA7 proteins, which overwhelms the process that assembles them together, causes cellular stress and disturbs the formation of calcium channels.

The result is a reduction of calcium flux in neurons," Schaaf said. "This is an important first step toward better understanding this condition and one day finding treatments that would improve the lives of these patients."



Source: Eurekalert
Font : A-A+

Advertisement

Advertisement
Advertisement

Recommended Readings

Latest Mental Health News

How Stress Induce Emotional Overeating?
Proenkephalin, a chemical molecule present in the brain's hypothalamus, is linked to emotionally driven overeating in response to stress and threats.
From Inflation to Global Affairs- Americans are Stressed on Holidays
Americans experience stress over the holidays, due to inflation, world affairs, rising flu and COVID-19 instances, and previous holiday melt-down.
Japanese Employees: Depressive Symptoms and Work Performance
Evaluating stress levels to improve employee mental health and sleep has shown to be effective in enhancing work performance.
Potential Role of Inflammation in Suicide Risk
Excessive inflammation and the loss of critical brain protection mechanisms have been found as a potential player in suicide risk.
Brain Taurine Levels Linked to Depression
The hippocampal taurine concentration is 20% lower in women affected by depression, stated new research.
View All
This site uses cookies to deliver our services.By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use  Ok, Got it. Close
×

Link Between CHRNA7 Gene and Neuropsychiatric Disorders Personalised Printable Document (PDF)

Please complete this form and we'll send you a personalised information that is requested

You may use this for your own reference or forward it to your friends.

Please use the information prudently. If you are not a medical doctor please remember to consult your healthcare provider as this information is not a substitute for professional advice.

Name *

Email Address *

Country *

Areas of Interests