Decline of hearing ability: Indian, US experts find gene role

Listening

In a path-breaking research which may have implications for those suffering from a decline of their cognitive and hearing abilities, Indian and American experts have established the role of a specific gene in triggering such conditions.

Experts of Sir Ganga Ram Hospital and University of Louisville School of Medicine stated that the MMP-9 gene plays a major role in causing decline of cognitive and hearing functions and removal of the said gene decreases
Hyperhomocysteinemia-induced cognitive and hearing dysfunctions.

Hyperhomocysteinaemia (HHcy) is a medical condition arising due to an abnormally high level of homocysteine in the blood, experts said.

“There is a role of MMP-9 in decline of cognitive and hearing functions. The ablation of MMP-9 decreases Hyperhomocysteinemia-induced cognition and hearing

dysfunction. This research was carried out on mice but has large implication for humans,” said Dr Seema Bhargava, lead author of the research and Senior Consultant, Department of Biochemistry, Sir Ganga Ram Hospital.

MMP-9 gene is a matrix metallopeptidase which helps in wound healing, cell migration, learning, memory and various other functions.

Currently, 45 per cent of adults in India between 45-92 years of age suffer from hearing impairment. Deficiency of Vitamin B-12 and folate (another form of vitamin) and high homocysteine levels have also been associated with impaired
hearing in women.

“It is important to identify individuals at risk for HHcy (e.g. elderly people)… To reduce homocysteine levels, adequate vitamin supplements should be given. However, if HHcy is already present, vitamins will take several months to reduce the concentration of homocysteine.

“Our study has advocated the role of MMP-9 inhibitors by pharmaceutical companies as a therapeutic option,” Bhargava said.
The research was published in the May edition of Journal of Molecular Biology Reports.

Source: Zee news


Gene linked to deadly breast cancer found

Scientists from Weill Cornell Medical College and Houston Methodist have found that a gene previously unassociated with breast cancer plays a pivotal role in the growth and progression of the triple negative form of the disease.

Their research suggests that targeting the gene may be a new approach to treating the disease.

About 42,000 new cases of triple negative breast cancer (TNBC) are diagnosed in the United States each year, about 20 percent of all breast cancer diagnoses. Patients typically relapse within one to three years of being treated.

Senior author Dr. Laurie H. Glimcher, the Stephen and Suzanne Weiss Dean of Weill Cornell Medical College, wanted to know whether the gene – already understood from her prior work to be a critical regulator of immune and metabolic functions – was important to cancer’s ability to adapt and thrive in the oxygen- and nutrient-deprived environments inside of tumors.

Using cells taken from patients’ tumors and transplanted into mice, Dr. Glimcher’s team found that the gene, XBP1, is especially active in triple negative breast cancer, particularly in the progression of malignant cells and their resurgence after treatment.

“Patients with the triple negative form of breast cancer are those who most desperately need new approaches to treat their disease,” Dr. Glimcher, who is also a professor of medicine at Weill Cornell said.

“This pathway was activated in about two-thirds of patients with this type of breast cancer. Now that we better understand how this gene helps tumors proliferate and then return after a patient’s initial treatment, we believe we can develop more effective therapies to shrink their growth and delay relapse,” the researcher added.

The study is published in the journal Nature.

Source: yahoo news


Gene involved in response to cocaine identified

Scientists, led by an Indian-origin researcher, have identified a gene that may determine the intensity of our response to cocaine.

Researchers at the University of Texas Southwestern suspect that the newly identified gene, Cyfip2, determines how mammals respond to cocaine, although it is too soon to tell what the indications are for humans or for addiction.

The findings evolved from examining the genetic differences between two substrains of the standard C57BL/6 mouse strain: a ‘J’ strain from the Jackson Laboratory (C57BL/6J) in US and an ‘N’ strain from the National Institutes of Health (C57BL/6N).

The study, with Dr Vivek Kumar as the lead author, compared the two strains of mice and used their differential responses to cocaine to identify the causative gene.

“We found that the ‘N’ strain has accumulated mutations over time, one of which has a very strong effect on cocaine response,” said Dr Joseph Takahashi, chair of neuroscience and a Howard Hughes Medical Institute investigator at UT Southwestern and the senior author of the study.

“We propose that CYFIP2 – the protein produced by the Cyfip2 gene – is a key regulator of cocaine response in mammals,” he said.

“We identified this gene by first using a forward genetics strategy to search for differences in traits between the two mouse strains. We found a difference in cocaine response between them, with the C57BL/6N strain showing a reduced behavioural response,” Takahashi said.

“We then carried out genetic mapping and whole genome sequencing, which allowed us to pinpoint the Cyfip2 gene as the causative one in a rapid and unambiguous way,” he added.

The study was published in the journal Science.

Source: Deccan chronicle


Gene test can help recommend best psychiatric medications for patients

Psychiatrists can use a simple genetic test to determine which psychoactive medications will be most easily metabolized by their patients. And a third clinical study has confirmed that this test has a positive effect on treatment outcome.

The Pine Rest study, published in Discovery Medicine, showed that when psychiatrists have their patients use GeneSite, those in the group whose treatment is guided by the technology showed a greater than two-fold response and remission rate.

GeneSite only requires swabbing the inside of the cheeks and sending the swab into a central lab. Basically, the test segments medications into “green” (use as directed), “yellow” (use with caution) or “red” (use with increased caution) categories, depending on the way a patient’s unique genomic makeup will interact with psychiatric medicines.

Psychiatrists who used GeneSite in the study were twice as likely to switch medications or adjust dosages of medications. In fact, 100 percent of clinicians using GeneSite made such changes, whereas only 50 percent of clinicians without the guidance did so.

The results of the Pine Rest study are similar to those of the La Crosse Study, published in July 2013 in Pharmacogenetics and Genomics. In that study of 227 participants, the GeneSite-guided group experienced a more than two-fold improvement in symptoms and likelihood to achieve remission.

Given the repeated success of GeneSite in these trials, I now use it frequently to help tailor medication treatment for patients. I suggest that you speak with your psychiatrist about it, as well.

Source: top news today