Friday 17 February 2017

Nasty Designer?

Parasitic worm may trigger mystery nodding syndrome | Science

Like all parasites, which have a ready explanation in terms of evolutionary biology, parasitic worms which make children sick and die present Intelligent (sic) Design advocates with special problems, not the least of which is one of creationism's own making.

The problem is that creationists presented with these especially nasty inventions of any assumed intelligence invariably fall back on 'The Fall' and say God allowed evil to enter the world because Eve sinned, so it's all our fault really. The problem for Intelligent (sic) Design advocates is that ID was invented as a concept to make creationism look like science so it could be inserted into American school science classes despite the 'Establishment Clause' and taught at tax-payers expense to vulnerable children.

The problem though is that 'The Fall' is an entirely religious explanation as is the stuff about sin and why we have evil. It simply isn't a scientific explanation but a superstitious one for which there is not a scrap of evidence and which of course is entirely untestable and unfalsifiable.

So, here's a challenge for an creationist who hasn't stopped reading by this point. Explain the following in terms of an intelligent plan by an intelligent designer and without resorting to religious superstition and tales from holy books, please.

Nodding Syndrome. Another triumph for the Intelligent Designer?
Between 1990 and 2013 thousands of children suddenly developed a strange form of epilepsy in which, in response to food or cold, they began nodding their head uncontrollably. Over time the seizures often worsened leaving the children severely disables. Many died through malnutrition, accident or secondary infections. In some communities roughly half of all families had at least one child with the condition. In Uganda alone some 1600 children had been affected by 2013.

Researchers had noticed a coincidence between the area where nodding syndrom was endemic and the area where infection with the parasitic worm, Onchocerca volvulus, which causes river blindness was found. The problem was that the worm was not known to invade the nervous system and no-one could establish a causal link. On the one hand, O. volvulus had been a problem long before nodding syndrome arose; on the other had, treating infection with the drug ivermectin reduced the incidence of nodding syndrome in Uganda to just about zero.

But now, a team of researchers believe they have established a causal link via an autoimmune response triggered in part by the patient making antibodies to an O. volvulus protein which is very similar in shape to the human protein leiomodin-1 which is found in the nervous system and brain, as well as in smooth muscle and thyroid cells where it is believed to influence cell shape. The team believe the antibody to the worm protein also attacks the similarly-shaped leiomodin-1 making the patient attack his or her own nervous system.

The research was conducted by a team led by neuroimmunologists Avindra Nath and Tory Johnson of the National Institutes of Health in Bethesda, Maryland.

Linking parasitic infection to autoimmune epilepsy
Nodding syndrome is a unique seizure disorder affecting children in parts of East Africa. The cause of nodding syndrome has been an enigma, although an epidemiological association with the parasite Onchocerca volvulus has been established. Johnson et al. demonstrate that patients with nodding syndrome have autoantibodies to leiomodin-1 that are neurotoxic in vitro and that leiomodin-1 is expressed in regions of the brain affected during disease. Leiomodin-1 antibodies cross-react with O. volvulus proteins, linking the parasite to the autoantibody. Thus, nodding syndrome may be an autoimmune epilepsy initiated by a parasitic infection and may be preventable by treatment with antiparasitic strategies such as the drug ivermectin.

Nodding syndrome is an epileptic disorder of unknown etiology that occurs in children in East Africa. There is an epidemiological association with Onchocerca volvulus, the parasitic worm that causes onchocerciasis (river blindness), but there is limited evidence that the parasite itself is neuroinvasive. We hypothesized that nodding syndrome may be an autoimmune-mediated disease. Using protein chip methodology, we detected autoantibodies to leiomodin-1 more abundantly in patients with nodding syndrome compared to unaffected controls from the same village. Leiomodin-1 autoantibodies were found in both the sera and cerebrospinal fluid of patients with nodding syndrome. Leiomodin-1 was found to be expressed in mature and developing human neurons in vitro and was localized in mouse brain to the CA3 region of the hippocampus, Purkinje cells in the cerebellum, and cortical neurons, structures that also appear to be affected in patients with nodding syndrome. Antibodies targeting leiomodin-1 were neurotoxic in vitro, and leiomodin-1 antibodies purified from patients with nodding syndrome were cross-reactive with O. volvulus antigens. This study provides initial evidence supporting the hypothesis that nodding syndrome is an autoimmune epileptic disorder caused by molecular mimicry with O. volvulus antigens and suggests that patients may benefit from immunomodulatory therapies.

But this still doesn't tell the whole story because, although the correlation between the syndrome and infection with O. volvulus looks very strong, it doesn't explain why the nodding syndrome never appeared earlier when river blindness was common. It seems very likely then that the autoimmune response has a complex cause involving other factors in addition to infection by O. volvulus; a virus, malnutrition, etc.

However, since Intelligent (sic) Design proponents attribute everything to their assumed designers intelligent intent, any explanation they come up with must also take account of these other factors. Clearly, any real intelligent designer would be capable of designing a syndrome with multiple causes. So, given that they believe their hypothesis of an intelligent designer designing everything, gives a much better explanation of biology than evolution, perhaps a creationist would like to offer one here.

What was the presumed Intelligent (sic) Designer's purpose in designing the parasitic worm O. volvulus? Why did it then design an immune system to help the worm's victim combat infection? And why did it design an antibody which attacks children's nervous system causing them to become sick, disabled and eventually dead, probably with the assistance of other environmental factors yet to be identified?

The evolutionary explanation is simple; there is no plan. How about an Intelligent (sic) Design explanation? And no religion remember, because that gives the game away.

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