Tag Archives: genetic engineering

RNA interference

Monsanto is trying to use genetic technology to kill honeybee pests.

RNA can also “silence” specific genes, preventing an organism from using them to make proteins. In 1998 scientists discovered that they could engineer stretches of double-stranded RNA to do the same thing. As a lab technique, RNA interference—or RNAi—turned out to be useful for learning about genes by turning them off. It also showed promise in fighting viruses, cancers, and even harmful pests and parasites. The researchers at the seminar were talking about using RNAi to prevent mosquitoes from spreading malaria, but that gave Hayes another idea. “I thought, could this be adapted to honeybee predator control?” In other words: to kill mites…

Traditional pesticides act like chemical backhoes, killing their targets (beetles, weeds, viruses) but harming good things along the way (beneficial insects, birds, fish, humans). RNAi, in theory, works instead like a set of tweezers, plucking its victims with exquisite specificity by clicking into sequences of genetic code unique to that organism. “If you could design an ideal pesticide, this is the stuff you’re looking for,” says Pamela Bachman, a toxicologist at Monsanto.

 

gene circuits

Here’s another article on the idea of designed biological circuits.

Synthetic mixed-signal computation in living cells

Living cells implement complex computations on the continuous environmental signals that they encounter. These computations involve both analogue- and digital-like processing of signals to give rise to complex developmental programs, context-dependent behaviours and homeostatic activities. In contrast to natural biological systems, synthetic biological systems have largely focused on either digital or analogue computation separately. Here we integrate analogue and digital computation to implement complex hybrid synthetic genetic programs in living cells. We present a framework for building comparator gene circuits to digitize analogue inputs based on different thresholds. We then demonstrate that comparators can be predictably composed together to build band-pass filters, ternary logic systems and multi-level analogue-to-digital converters. In addition, we interface these analogue-to-digital circuits with other digital gene circuits to enable concentration-dependent logic. We expect that this hybrid computational paradigm will enable new industrial, diagnostic and therapeutic applications with engineered cells.

CRISPR

Here’s some more info on CRISPR, a genetic engineering technique some people are saying will be revolutionary.

 The Bacterial Origins of the CRISPR Genome-Editing Revolution
Sontheimer Erik J. and Barrangou Rodolphe. Human Gene Therapy. July 2015, 26(7): 413-424. doi:10.1089/hum.2015.091.

Like most of the tools that enable modern life science research, the recent genome-editing revolution has its biological roots in the world of bacteria and archaea. Clustered, regularly interspaced, short palindromic repeats (CRISPR) loci are found in the genomes of many bacteria and most archaea, and underlie an adaptive immune system that protects the host cell against invasive nucleic acids such as viral genomes. In recent years, engineered versions of these systems have enabled efficient DNA targeting in living cells from dozens of species (including humans and other eukaryotes), and the exploitation of the resulting endogenous DNA repair pathways has provided a route to fast, easy, and affordable genome editing. In only three years after RNA-guided DNA cleavage was first harnessed, the ability to edit genomes via simple, user-defined RNA sequences has already revolutionized nearly all areas of biological science. CRISPR-based technologies are now poised to similarly revolutionize many facets of clinical medicine, and even promise to advance the long-term goal of directly editing genomic sequences of patients with inherited disease. In this review, we describe the biological and mechanistic basis for these remarkable immune systems, and how their engineered derivatives are revolutionizing basic and clinical research.

genetic sequencing: what’s it good for?

Do you find genetic sequencing interesting, but you’ve been struggling to find a practical application? Look no further:

According to Hutchinson, Sweet Peach will provide women with kits allowing them to swab their vaginas at home, then mail the swab into a lab which will sequence the genomes of their vaginal bacteria. Sweet Peach will then create a personalized probiotic — targeting UTIs and yeast infections — based on each woman’s swab. Women will be able to purchase a monthly regimen or a longer “subscription” based on their needs. More information will be available when the company launches their crowdfunding campaign this coming week.

“It’s nothing about scent,” Hutchinson told The Huffington Post in a phone interview. “A vagina should smell like a vagina, and anyone who doesn’t think that doesn’t deserve to be near one.”

Okay, touche, nothing about scent… but I can think of plenty of applications above the waist that do involve scent. Bad breath and armpit odor are caused mainly by sulfate reducing bacteria, I think, so introduce another harmless organism that can out-compete them, and problem solved – in fact, showering too often might tend to disrupt your perfectly balanced armpit ecosystem. How about some genetically customized pro-biotic mouthwash and deodorant? You could come back from your next camping trip smelling better than when you left! Or on a more serious note, how about healthy teeth and gums without brushing?