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Archive for the ‘genetics’ category: Page 259

Sep 18, 2020

Biologists create new genetic systems to neutralize gene drives

Posted by in categories: bioengineering, biotech/medical, genetics

In the past decade, researchers have engineered an array of new tools that control the balance of genetic inheritance. Based on CRISPR technology, such gene drives are poised to move from the laboratory into the wild where they are being engineered to suppress devastating diseases such as mosquito-borne malaria, dengue, Zika, chikungunya, yellow fever and West Nile. Gene drives carry the power to immunize mosquitoes against malarial parasites, or act as genetic insecticides that reduce mosquito populations.

Although the newest gene drives have been proven to spread efficiently as designed in laboratory settings, concerns have been raised regarding the safety of releasing such systems into wild populations. Questions have emerged about the predictability and controllability of gene drives and whether, once let loose, they can be recalled in the field if they spread beyond their intended application region.

Now, scientists at the University of California San Diego and their colleagues have developed two new active genetic systems that address such risks by halting or eliminating gene drives in the wild. On Sept.18, 2020 in the journal Molecular Cell, research led by Xiang-Ru Xu, Emily Bulger and Valentino Gantz in the Division of Biological Sciences offers two new solutions based on elements developed in the common fruit fly.

Sep 15, 2020

Ancient DNA is revealing the genetic landscape of people who first settled East Asia

Posted by in categories: biotech/medical, genetics

By studying the DNA of people who lived in East Asia thousands of years ago, scientists are starting to untangle how the region was populated.

Sep 15, 2020

Twist on CRISPR Gene Editing Treats Adult-Onset Muscular Dystrophy in Mice

Posted by in categories: bioengineering, biotech/medical, genetics

Myotonic dystrophy type I is the most common type of adult-onset muscular dystrophy. People with the condition inherit repeated DNA segments that lead to the toxic buildup of repetitive RNA, the messenger that carries a gene’s recipe to the cell’s protein-making machinery. As a result, people born with myotonic dystrophy experience progressive muscle wasting and weakness and a wide variety of other debilitating symptoms.

CRISPR-Cas9 is a technique increasingly used in efforts to correct the genetic (DNA) defects that cause a variety of diseases. A few years ago, University of California San Diego School of Medicine researchers redirected the technique to instead modify RNA in a method they call RNA-targeting Cas9 (RCas9).

In a new study, publishing September 14, 2020 in Nature Biomedical Engineering, the team demonstrates that one dose of RCas9 gene therapy can chew up toxic RNA and almost completely reverse symptoms in a mouse model of myotonic dystrophy.

Sep 15, 2020

23andMe research finds possible link between blood type and Covid-19

Posted by in categories: biotech/medical, genetics

A forthcoming study from 23andMe shows that a person’s genetic code could affect how severely they experience Covid-19.

Sep 14, 2020

New Map Charts Genetic Expression Across Tissue Types, Sexes

Posted by in categories: biotech/medical, genetics, life extension, neuroscience, sex

From the data, the GTEx team could identify the relationship between specific genes and a type of regulatory DNA called expression quantitative trait loci, or eQTL. At least one eQTL regulates almost every human gene, and each eQTL can regulate more than one gene, influencing expression, GTEx member and human geneticist Kristin Ardlie of the Broad Institute tells Science.

Another major takeaway from the analyses was that sex affected gene expression in almost all of the tissue types, from heart to lung to brain cells. “The vast majority of biology is shared by males and females,” yet the gene expression differences are vast and might explain differences in disease progression, GTEx study coauthor Barbara Stranger of Northwestern University’s Feinberg School of Medicine tells Science. “In the future, this knowledge may contribute to personalized medicine, where we consider biological sex as one of the relevant components of an individual’s characteristics,” she says in a statement issued by the Centre for Genome Regulation in Barcelona, where some of the researchers who participated in the GTEx project work.

Another of the studies bolsters the association between telomere length, ancestry, and aging. Telomere length is typically measured in blood cells; GTEx researchers examined it in 23 different tissue types and found blood is indeed a good proxy for overall length in other tissues. The team also showed that, as previously reported, shorter telomeres were associated with aging and longer ones were found in people of African ancestry. But not all earlier results held; the authors didn’t see a pattern of longer telomeres in females or constantly shorter telomeres across the tissues of smokers as previous studies had.

Continue reading “New Map Charts Genetic Expression Across Tissue Types, Sexes” »

Sep 12, 2020

Cancer Projects to Diversify Genetic Research Receive New Grants

Posted by in categories: biotech/medical, genetics

Because much cancer research and clinical trials have been based on white populations, efforts to explore the ways race and ethnicity influence disease are underway.

Sep 11, 2020

This Horse Cloned from 40-Year-Old Material Could Save Its Species

Posted by in categories: biotech/medical, genetics

Recently, San Diego Zoo partnered up with the wildlife preservation group Revive and Restore and a pet cloning company ViaGen Equine to create an exact copy of Kuporovic. The embryo was planted in a surrogate mother, a common horse.

Shawn Walker, the chief science officer at ViaGen Equine reports “This new Przewalski’s colt was born fully healthy and reproductively normal. He is head butting and kicking when his space is challenged, and he is demanding milk supply from his surrogate mother.”

Continue reading “This Horse Cloned from 40-Year-Old Material Could Save Its Species” »

Sep 9, 2020

Kurt the cloned horse was created using 40-year-old genetic material

Posted by in categories: biotech/medical, genetics

An endangered type of horse has successfully been cloned by scientists.

Kurt is a newborn Przewalski’s horse, a rare and endangered horse native.

He was born this year on August 6 after experts used genetic material that had been cryopreserved for 40 years.

Continue reading “Kurt the cloned horse was created using 40-year-old genetic material” »

Sep 8, 2020

Researchers find conserved regeneration-responsive enhancers linked to tail regeneration in fish

Posted by in categories: biotech/medical, genetics

A team of researchers from Stowers Institute for Medical Research, Howard Hughes Medical Institute and Stanford University has discovered conserved regeneration-responsive enhancers linked to tail regeneration in fish common to two species. In their paper published the journal Science, the group describes their genetic study of two fish species and what they learned about the role of conserved regeneration-responsive enhancers in allowing the fish to regenerate tail parts.

As the researchers note, some species are able to regenerate parts of their body when they are lost. For instance, lizards can regrow lost tails, while many other animals, including most mammals, cannot regrow damaged body parts. Despite much research, scientist have not been able to explain this. In this new effort, the researchers have found what they believe to be a major clue—conserved regeneration-responsive enhancers.

Continue reading “Researchers find conserved regeneration-responsive enhancers linked to tail regeneration in fish” »

Sep 6, 2020

Engineers Genetically Reprogram Yeast Cells to Become Microscopic Drug Factories

Posted by in categories: biotech/medical, chemistry, food, genetics

Since antiquity, cultures on nearly every continent have discovered that certain plant leaves, when chewed or brewed or rubbed on the body, could relieve diverse ailments, inspire hallucinations or, in higher dosages, even cause death. Today, pharmaceutical companies import these once-rare plants from specialized farms and extract their active chemical compounds to make drugs like scopolamine for relieving motion sickness and postoperative nausea, and atropine, to curb the drooling associated with Parkinson’s disease or help maintain cardiac function when intubating COVID-19 patients and placing them on ventilators.

Now, Stanford engineers are recreating these ancient remedies in a thoroughly modern way by genetically reprogramming the cellular machinery of a special strain of yeast, effectively transforming them into microscopic factories that convert sugars and amino acids into these folkloric drugs, in much the same way that brewers’ yeast can naturally convert sugars into alcohol.