Viroporin
Jeg kom over denne spennende artikkelen i sommer og har spart på den med hensikt om å legge den ut i bloggen min, men det har liksom aldri blitt noe av det – før nå. Årsaken til at jeg nå legger det ut er at jeg i dag oppdaget at det har skjedd en spennende utvikling i saken.

Artikkelen er skrevet av en student, Abbie Smith, som jobber til daglig med HIV-viruset, og hovedpoenget i artikkelen er å vise til et konkret eksempel som motbeviser IDernes hoved-argument om at evolusjon ikke kan produsere nye egenskaper i en organisme. Tilhengere av Intelligent Design hevder at alle mutasjoner alltid er skadelige og at det ikke finnes et eneste eksempel på at mutasjoner har “skapt ny informasjon” (hva nå enn det betyr) eller frembringt en fordelaktig egenskap. Dette er også hovedargumentet i Michael Behes siste bok, The Edge of Evolution.


Selv om artikkel er veldig “teknisk” og detaljene går langt over hodet mitt, så er det lett å se at hovedessensen i det hun skriver totalt radbrekker Behes sentrale argument, som han fremstiller slik:

Like malaria, HIV is a microbe that occurs in astronomical numbers. What’s more, its mutation rate is 10,000 times greater than that of most other organisms. So in just the past few decades HIV has actually undergone more of certain kinds of mutations than all cells have endured since the beginning of the world. Yet all those mutations, while medically important, have changed the functioning virus very little. It still has the same number of genes that work in the same way. There is no new molecular machinery. If we see that Darwin’s mechanism can only do so little even when given its best opportunities, we can decisively conclude that random mutation did not build the machinery of life.

Men, som Abbie Smith påpeker, ble et nytt gen oppdaget tilbake i 1988. Genet heter Vpu, og Smith forklarer i detalj hvorfor og hvordan dette totalt undergraver hans egen påstand om at HIV-viruset ikke har endret seg over tid på tross av hyppige mutasjoner. Se også denne illustrasjonen som viser dette tydelig.

Det verste av alt er at denne informasjonen har vært tilgjengelig i snart 20 år, men Behe skriver likevel en bok til forsvar for Intelligent Design hvor han totalt overser denne helt sentrale informasjonen. Velkjent taktikk fra IDerne. Som Abbie Smith skriver i artikkelen:

Look, the fact of the matter is, all of this information on Vpu is publicly available. No one was hiding this information. This wasn’t a ‘trick.’ Vpu was not discovered yesterday – it was discovered in 1988. There is no excuse for you to write an entire book on the premise of HIV not being able to do something, when it is clear that these impossible feats did happen. This is just one of a billion plus examples of lazy Creationists taking advantage of the ignorance of their followers. I’m just a friggen pre-grad student who knew what the HIV-1 genome looked like and had a few minutes to do a PubMed search. I haven’t even taken a course in biochemistry.

Etter et par måneder kom endelig et svar fra Michael Behe. Et svar som var både arrogant og som ignorerte hennes sentrale poeng. Han konkluderer som følger:

Darwinists overlook the considerable power of the example of the relatively minor changes in HIV: there have been a truly astronomical number of copies produced in just the past fifty years or so. And because of its much increased mutation rate, it has undergone in the past half century as many of some kinds of mutations as all the cells have undergone in the history of the world. If Darwinism had the power that its boosters claim, we should expect to see truly fundamental changes. Yet despite the enormous number of opportunities, only minor changes have appeared. That is very strong evidence of the strict limits on what Darwinian processes can accomplish.

I dag ble det lagt ut et svar til Behe skrevet av Ian Musgrave, en av Smiths lærere og han som har laget illustrasjonene til hennes artikkel om Vpu. Hans svar starter slik:

I have recently read your response to Abbie Smith’s article on the HIV-1 protein VPU. Ms Smith showed how Vpu’s recently evolved viroporin activity directly contradicts your statement that HIV has evolved no new biding sites since it entered humans (Edge of Evolution, page 143 and figure 7.4, page 144 ). I was greatly disappointed in your response. I must admit to having a special involvement in this case. Firstly, I drew the illustrations for Ms Smith’s article, and its follow up. But secondly, as a member of my professional association’s education committee, I am directly concerned with the support and nurturing of the new generations of enquiring minds, those that we will pass the torch of enquiry on to when we retire. It is in this regard that your response very disturbing. It is almost the exact opposite of what a concerned scientist and science communicator should have done.

It was bad enough that you chose to ignore her for over two months and then did not do her the courtesy of replying on her blog (1). It was bad enough that you chose to start by belittling her and playing the “I’m a Professor and she is a mere student” card (conveniently ignoring the fact that she actually works on HIV). This is particularly egregious in science, where we pay attention to the evidence and logic of an argument, rather than the letters after an author’s name. Doubly so if we wish to guide young scientists into a demanding profession.

But by far the worst, you ignored her core argument. That in the space of a decade HIV-1 Vpu developed a series of binding sites that made it a viroporin, a multisubunit structure with a function previously absent from HIV-1. Dr. Behe, it is not enough to cite a generalist review and claim that the differences between HIV-1 strains are “not all that great”. You actually have to show why Vpu developing binding sites to form a multi-subunit structure with a novel function does not falsify your claim that HIV has developed no new binding sites. Ironically, the very paper you cite to dismiss Ms Smith contains evidence of at least two new binding sites in HIV. I will not dwell on this any further, as Ms Smith is producing her own response.

Han fortsetter med å påpeke hvordan Behe misforstår Smiths argument. Spennende lesning!

Som Musgrave skriver, så er Abbie Smith i gang med sitt eget svar til Behe, og jeg venter i spenning. Det er fint med litt ammunisjon i kanonen når man skal argumentere med kreasjonister som har lest seg blinde på AiG-tøvet.