Re-Making Mosquitoes

Malaria, a devastating parasitic disease, kills millions of children per day in many countries in Africa, South America, & South/Southeast Asia. It is caused by parasites in the Plasmodium genus. These parasites are transmitted via female Anopheles mosquitos thus spreading malaria from person to person.

For the past three decades, scientists have been looking for clues and for evidence as to how to device an "intervention method".

There are three major concerns:
1) Can we re-engineer mosquitoes so they canNOT become "carriers" for malaria parasites?
2)Will these mosquitoes survive, if their genomes are modified?
3)Will they procreate and make a new population outside of laboratory environment?

The first two of these concerns have been brought to our attention when scientists began to publish their findings in 2003. They found that they could re-engineer certain species of Anopheles with an altered genome. A special protein peptide called SM1 blocks mosquitoe's gut and thus prevents Plasmodium development. It can be genetically engineered into the mosquitoe genome such that mosquitoes can pass-on the SM1 gene to their progenies.

Will these progenies surivive when they come in contact with infected blood? The most recent research article addressed this question. SM1-Mosquitoes were tested for survival fitness, compared with regular wildtype mosquitoes of the same species, when they were exposed to infected blood in the laboratory. If mosquitoes had only one copy of the SM1 incorporated into their genome, rather than 2 copies, they could survive better but doesn't reduce mosquitoe's resistence to malaria. Their experiments have to be repeated, of course, for Plasmodium species specific to human infections. It can turn out to be a powerful new technology for the future.

However, I cannot stop to wonder: Will a re-engineered mosquito species replace what's already in existence in nature? How many "mosquito generations" will it take??



Marrelli M. T., Li C., Rasgon J. L. & Jacobs-Lorena M. Proc. Natl Acad. Sci. USA, 104 . 5580 - 5583 (2007).
Catteruccia F., Godray H. C. & Crisanti A. Science, 299 . 1225 - 1227 (2003).
Riehle M. M., et al. Science, 312. 577 - 579 (2006).

An Oasis in Anza-Borrego Desert Park

Waiting to stretch your legs and fill-up your lungs with fresh air?

Go to Anza-Borrego Desert. Then? Camp there for at least one night.

The weather clock was kind to us. We pitched a tent and setup a bonfire . Under the starry sky, everyone counted stars and relaxed over a glass of wine. And, let me not forget, enjoy some excellent grills -- coyotes like meaty grills, just FYI ;-)

Best part of camping is to go on a hike. By the way, the name "Anza Borrego" comes from its Spanish explorer, Juan Bautista de Anza, and the Spanish word for "bighorn sheep", borrego. Most people go to the park to enjoy its hiking trails draped around its sweeping rocky landscape, and wildlife and blooming flowers (if there is enough rain during the winter...) If the season is right, you will find some bighorn sheep trudging over sides of the mountains, proudly claiming their land!

Hurray!

"Wandering Mind" Still Thinks

Is our brain "doing" anything when we daydream and wander? Is our brain active at all, when we seem unoccupied by tasks at hand?

YES and YES.

Recently, psychologists published a study where they measured people's brain activity when their task-at-hand is not demanding (just "routine work"). They found that their brains generate Stimulus-Independent-Thought (SIT). The finding led them to think that the brain is active even when we are not doing anything requiring our full-attention. They examined their participants and compared their levels of SIT when they performed, 1) a "routinely practised" task and, 2) a completely "new and novel" task. There was definitely more brain activity -SIT- found in the first case.

Psychologists termed what they found "our psychological baseline." Such baseline engages a particular region in our brain responsible for generating spontaneous-thought. That's their hypothesis for now, at least.

What does it all mean? What's the brain doing when we daydream?
Well....We are "thinking", though we are not aware of it. Still thinking!!!

One more question:
How does a "thought" form then?


Sources:
Science 19 January 2007: Vol. 315. no. 5810, pp. 393 - 395
Science 24 November 2006: Vol. 314. no. 5803, pp. 1249 - 1250