Mike the Mad Biologist

Blogging on Peer-Reviewed Research
…the Chikungunya virus might have something to say about that (if it could speak). From PLoS Pathogens:

Chikungunya virus (CHIKV) is an emerging arbovirus associated with several recent large-scale epidemics of arthritic disease, including one on Reunion island, where there were approximately 266,000 cases (34% of the total island population). CHIKV is transmitted by Aedes species mosquitoes, primarily Ae. aegypti. However, the 2005-2006 CHIKV epidemic on Reunion island was unusual because the vector responsible for transmission between humans was apparently the Asian tiger mosquito, Ae. albopictus. Interestingly, the same epidemic was associated with a strain of CHIKV with a mutation in the envelope protein gene (E1-A226V). In this work we investigated the role of the E1-A226V mutation on the fitness of CHIKV in Ae. aegypti and Ae. albopictus mosquitoes. We found that E1-A226V is directly responsible for CHIKV adaptation to Ae. albopictus mosquitoes, which provides a plausible explanation of how this mutant virus caused an epidemic in a region lacking the typical vector. This research gives a new insight into how a simple genetic change in a human pathogen can increase its host range and therefore its geographic distribution. Ae. albopictus is abundant and widely distributed in urban areas of Europe and the United States of America, and this work suggests that these areas are now vulnerable to CHIKV establishment.

Let’s just try to ignore that last sentence. Onto the creationists. One common creationist argument is that mutation can’t be responsible for adaptive change because mutations are always harmful or cause of loss of function. The unspoken, illogical corollary stemming from this discipline of Vichy science is that God must therefore create things and not evolution. Nuts, but people really do walk among us who thinkengage in non-random neurological activity like this.

What this article suggests is that the species range of the Chikungunya virus has increased due to a…mutation. It doesn’t seem to have significantly affected the novel virus’ ability to infect the original mosquito host either.

But what do these authors know? They’re just biologists.

Citation: Tsetsarkin KA, Vanlandingham DL, McGee CE, Higgs S (2007) A Single Mutation in Chikungunya Virus Affects Vector Specificity and Epidemic Potential. PLoS Pathog 3(12): e201 doi:10.1371/journal.ppat.0030201

Comments

  1. #1 Ian
    December 19, 2007

    “But what do these authors know? They’re just biologists.”

    But they’re not _mad_ biologists!

  2. #2 FlyonTheWall
    December 19, 2007

    I just read a very interesting article a few days ago on how viruses and our own DNA have played crucial roles in human evolution, and how a lot of the junk between active gene’s, and some active gene’s themselves, are fused viruses from millennia past. And they found this in all species.

    They even been able to isolate the broken chains, put them back together, and bring back viruses that effected life millions of years ago. Crazy stuff! Let creationists think what they like, hopefully Darwinism will deal rightfully with them just like parents who are against inoculation.

  3. #3 Lindbarger
    December 20, 2007

    Well, I have never argued that mutations are always harmful.

    But the overwhelming majority, that are not neutral, are.

    Why do you gloss this over?

  4. #4 Brian
    December 20, 2007

    Lindbarger, what is there to gloss over? Even accepting your contention, what does it imply?