Genetics & Molecular Biology

Significant progress has been made over the last 25 years to identify genetic abnormalities associated with congenital myasthenic syndromes (CMS) but many patients remain genetically undiagnosed. A new report identifies a gene defect in mitochondria, specifically the citrate carrier SLC25A1, that may underlie deficits in neuromuscular transmission seen in two siblings.

"While mitochondrial gene defects can cause a myriad of neurological disorders including myopathies and neuropathies, these have not been specifically implicated in defects of the neuromuscular junction," says Hanns Lochmüller, MD, Professor of Experimental Myology, Institute of Genetic Medicine, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, UK.


If you could live longer, would you be weaned on an extreme, emaciating diet?

The search for the foundation of youth has been happening forever and a popular idea in recent years has been caloric restriction - mice weaned on starvation diets live long and a new study of the tiny nematode worm C. elegans finds results even more alarming - it triggered a state of arrested development.


Researchers have developed a new technique to control populations of a major livestock pest in Australia and New Zealand.

They genetically modified lines of female Australian sheep blowflies (Lucilia cuprina), making female flies dependent upon a common antibiotic -
tetracycline
- to survive. 

Dr. Max Scott, professor of entomology at North Carolina State University, and colleagues say that female blowflies that did not receive the antibiotic died in the late larval or pupal stages, before reaching adulthood. Several genetically modified lines lacking tetracycline showed 100 percent female deaths.


Chronic tissue inflammation is typically associated with obesity and metabolic disease, but new research finds that a level of "healthy" inflammation is necessary to prevent metabolic diseases, such as fatty liver.


Mitochondria are cell organelles located within animal and human cells. They produce energy for the organism, possess their own genetic material - mitochondrial DNA (mtDNA) - and are transmitted exclusively by the mother.

Depending on their activity and tasks, different numbers of mitochondria are present in a cell - usually a few hundred to a thousand per body cell.


Some basic biology may need revising. It's broadly assumed that cells degrade and recycle their own old or damaged organelles, but researchers writing in PNAS say that some neurons transfer unwanted mitochondria, the tiny power plants inside cells, to supporting glial cells called astrocytes for disposal.  

The researchers looked specifically at the axons of retinal ganglion cells in mice, a type of neuron that transmits visual information from the eye to the brain. The investigation was prompted by observations while studying a mouse model of glaucoma that protein products from the retina were accumulating in the optic nerve head (ONH) just behind the eye. 


The kidney, unlike its neighbor the liver, was once understood to be a static organ once it had fully developed, but doctors have observed patients with kidney disease experiencing renal regeneration.  

A new study conducted by researchers at Sheba Medical Center, Tel Aviv University and Stanford University have pinpointed the precise cellular signaling responsible for renal regeneration and exposing the multi-layered nature of kidney growth. The research was conducted by principal investigators Dr. Benjamin Dekel of TAU's Sackler School of Medicine and Sheba Medical Center and Dr. Irving L. Weissman of Stanford University's School of Medicine, working with teams of researchers from both universities.


In the most comprehensive genetic study of the Mexican population to date, researchers from  Mexico's National Institute of Genomic Medicine (INMEGEN), UC San Francisco and Stanford University, have identified tremendous genetic diversity.

So much diversity there basically are no Mexicans.  But it explains some confounding aspects of Latino health, like why there is such a variety of health factors among Latinos of Mexican descent, including differing rates of breast cancer and asthma, as well as therapeutic response.  


Researchers have developed biomaterials for bone regeneration from beer brewing waste.

A molecular pathway called mTORC1 controls the conversion of unhealthy white fat into beige fat, an appealing target for increasing energy expenditure and reducing obesity, according to a new study. The team also found that a protein, Grb10, serves as the on-off switch for mTORC1 signaling and the "beigeing" of fat.