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Researchers have identified a gene variation that has a key influence on blood lipid levels and individuals' predisposition to heart attacks.

The discovery, made by a team from the University of Michigan and the Norwegian University of Science and Technology, could help scientists to develop treatments for high cholesterol and other lipid disorders.

Significantly, the formerly unrecognised gene has been overlooked during previous attempts to find genes that affect the risk of cardiovascular disease.

While the region of DNA in which it is located had been identified as important in controlling blood lipid levels, none of them had an obvious link to these levels. An entirely new approach was needed to make the connection.

In the paper Nature Genetics, the team described how they made the discovery. They scanned genetic information in a biobank of Norwegians, focussing on variations in genes that change the way proteins function. Most of what they found turned out to be already known to affect cholesterol levels and other blood lipids.

One gene, however, was discovered to influence lipid levels. A minority of Norwegians who carried a particular change in the gene TM6SF2 were found to be healthier and at reduced risk of suffering a heart attack.

When the researchers boosted or suppressed the gene in mice, it had the same effect on the animals' blood lipid levels.

"While genetic studies that focused on common variations may explain as much as 30 per cent of the genetic component of lipid disorders, we still don't know where the rest of the genetic risk comes from," said Cristen Willer, PhD, the senior author of the paper and an assistant professor of Internal Medicine, Human Genetics and Computational Medicine & Bioinformatics at the U-M Medical School.

"This approach of focusing on protein-changing variation may help us zero in on new genes faster."

The same gene may be involved in regulating lipid levels in the liver. However, more research is needed to ascertain the exact function of the protein and whether it can be targeted with drug therapies to help treat cardiovascular disease or liver disease.

A new study has revealed a microbial imbalance in the intestinal tract of patients suffering from Crohn's disease.

The project, which involved a number of institutions, was led by investigators from Massachusetts General Hospital (MGH) and the Broad Institute. 

Their research, published in the March 12th issue of Cell Host and Microbe, reports increased levels of harmful bacteria in the gastrointestinal tract of Crohn's sufferers and reduced levels of beneficial bacteria normally found in a healthy tract.

While previous studies have linked the excessive immune response characterised by Crohn's disease to an imbalance in the normal microbial population, the exact relationship has so far not been clear.

The current study used data from the RISK Stratification Study, which was designed to investigate microbial, genetic and other factors in a group of children newly diagnosed with Crohn's disease or other inflammatory bowel diseases.

Data was also obtained from an additional group of about 800 participants in previous studies, for a total of more than 1,500 individuals.

Advanced sequencing of the microbiome in tissue samples taken from sites at the beginning and the end of the large intestine revealed a significant reduction in the diversity of the microbial population of the patients, who had yet to receive any treatment for the disease.

Compared to the control group, the Crohn's patients exhibited an abnormal increase in the levels of harmful bacteria and a drop in noninflammatory and beneficial species. There was an even greater imbalance in samples from those with more severe symptoms.

"These results identifying the association of specific bacterial groups with Crohn's disease provide opportunities to mine the Crohn's-disease-associated microbiome to develop diagnostics and therapeutic leads," said senior author Ramnik Xavier, chief of the MGH Gastrointestinal Unit and director of the MGH Center for the Study of Inflammatory Bowel Disease.

Before Crohn's is diagnosed, antibiotics are often prescribed in an attempt to alleviate symptoms. However, samples obtained from those who were taking antibiotics revealed a more pronounced microbial imbalance, suggesting this treatment could exacerbate symptoms.

Further research will focus on the function of the microbes and their products, and the interaction of these with the patient's immune system.

Scientists at Brandeis University and the University of Pittsburgh have obtained evidence which supports Alan Turing's theories of morphogenesis.

While Mr Turing's accomplishments in the field of computer science are well-known, less is known about his influence on biology and chemistry.

In his only paper on biology, he put forward a theory of morphogenesis, explaining how identical copies of a single cell differentiate into an organism with separate structures.

Researchers have provided experimental evidence for Mr Turing's theory for the first time, publishing their findings in the Proceedings of the National Academy of Sciences.

The famous mathematician, who worked at Britain's code-breaking centre at Bletchley Park during the second world war, was the first to offer a theory of morphogenesis through chemistry.

He theorised that identical biological cells differentiate, change shape and create patterns through a process called intercellular reaction-diffusion.

According to the theory, chemicals react with each other and diffuse across space; they require an inhibitory agent, to suppress the reaction, and an excitatory agent, to activate the reaction. Chemically different cells are produced as a result of the chemical reaction, diffused across an embryo.

In order to test the hypothesis, scientists at Brandeis – Seth Fraden, professor of physics, and Irv Epstein, the Henry F Fischbach professor of chemistry – created rings of synthetic, cell-like structures with activating and inhibiting chemical reactions.

Mr Turing predicted six different patterns that could arise from this model and the scientists observed all of these, plus a seventh.

The researchers found that, in line with Mr Turing's theory, once-identical structures – now chemically different – also began to change in size due to osmosis.

It is hoped the research will aid the study of biological development and how similar patterns form in nature. It could also have an impact on materials science – Turing's model could help grow soft robots with certain patterns and shapes.

Last year, the Queen issued a posthumous pardon for Mr Turing, who was prosecuted for homosexuality in 1952 and committed suicide two years later.

A team of researchers has used stem cells to help understand the processes underlying the development of Alzheimer's Disease (AD) and to investigate new treatment possibilities.

Scientists at Brigham and Women's Hospital (BWH) used stem cells derived from related family members with a genetic predisposition to the disease.

Dr Tracy Young-Pearse, corresponding author of the study recently published in Human Molecular Genetics and an investigator in the Center for Neurologic Diseases at BWH, pointed out that postmortem tissue had typically been used in previous studies of the disease.

"In this study, we were able to generate stem cells from skin biopsies of living family members who carry a mutation associated with early-onset AD. We guided these stem cells to become brain cells, where we could then investigate mechanisms of the disease process and test the effects of newer antibody treatments for AD."

Skin biopsies were obtained from a 57-year-old father with AD and his 33 year-old daughter, who is currently asymptomatic for AD. Both individuals harbour the "London" familial AD Amyloid Precursor Protein (APP) mutation, V7171.

The biopsies were submitted to the Harvard Stem Cell Institute, where the cells were converted into pluripotent stem cells. The team then directed these into neurons specifically related to a particular region of the brain which is responsible for memory and cognitive function.

The scientists showed that the APPV7171 mutation alters APP subcellular location, amyloid-beta protein generation, and then alters Tau protein expression and phosphorylation. This impacts the Tau protein's function and activity.

Amyloid-beta antibodies were then tested on the affected neurons. The team demonstrated that the secondary increase in Tau can be rescued by treatment with the amyloid-beta protein antibodies, providing direct evidence linking disease-relevant changes in amyloid-beta to aberrant Tau metabolism in living cells obtained directly from an AD patient.

 Dr Young-Pearse said the research could be useful in testing and comparing amyloid-beta antibodies, which are proving to be a promising therapeutic technique if delivered early in the disease process.

New research conducted at the Translational Genomics Research Unit (TGen) has identified a key protein that helps prevent the destruction of lung cancer tumours, which could make radiation treatment and chemotherapy more effective.

Non small cell lung cancers (NSCLCs) account for 87 out of 100 lung cancers in the UK. Lung cancer is the second most common cancer diagnosed in the UK and the most common cause of cancer death in the UK, accounting for more than one in five deaths from the disease.

Platinum-derived chemotherapeutics, such as cisplatin, or radiation therapy are often used to treat the disease in the absence of more effective targeted therapies.

Studies previously conducted at TGen have shown that excessive activation of a cellular signaling mechanism known as TWEAK-Fn14 is linked to the survival and spread of cancer cells.

In a new study, published in the scientific journal Molecular Cancer Research, researchers found that a protein called Mcl-1 helps enable TWEAK-Fn14, which in turn helps protect NSCLC tumours from being destroyed by radiation and drugs.

"Our study demonstrates that the expression of Mcl-1 is necessary to promote the TWEAK-mediated survival of NSCLC tumor cells," said Dr Timothy Whitsett, an assistant professor in TGen's Cancer and Cell Biology Division, and the study's lead author. "By deactivating Mcl-1, we believe we can give these lung cancer patients a better response to standard therapy."

A drug called EU-5148 was used to block Mcl-1 function and halt the TWEAK-Fn14 cellular signaling mechanism. Inhibition of Mcl-1 enhanced chemo- and radio-sensitivity in NSCLC cells.

Dr Nhan Tran, an associate professor in TGen's Cancer and Cell Biology Division, and the study's senior author, said the TWEAK-Fn14 cellular pathway and the Mcl-1 protein are potential therapeutic interventions.

He added that bypassing these mechanisms would make it more difficult for lung cancer cells to evade therapies.

According to the team, more research is needed into the Mcl-1 and TWEAK-Fn14 mechanism. Clinical trials would follow, hopefully leading to more effective treatments that could reduce lung cancer mortality.