Genetic Throwbacks?

[Vita Curator]

I don't know if this is for real or not, one of my friends called me this afternoon and told me to watch NOVA on PBS this Tuesday Night.

The show is entitled Family That Walks On All Fours.

It profiles a family of five Turkish adults who walk in a manner that the human body is no longer built to do.  The scientist who discovered them calls them "genetic throwbacks". 

As I said, I don't know what this is all about, but it sounds like an interesting episode of NOVA.

[The Black Spot]

This was on the BBC show "Horizon" a few months ago (are Nova and Horizon the same show rebranded?)

Anyway, the thing I found most interesting was that the family in question walk on their wrists, while apes walk on their knuckles.

Wrists seem (to me at least) a bit too delicate to be weight bearing when bent; if this family are truely a form of throwback, it may help explain why our ancestors became true bipeds.

[Vita Curator]

I don't know if Horizon and NOVA are sister shows or not, I do know that my PBS station gets many of their fine shows from the BBC (I still watch old reruns of Are You Being Served?)

I am definitely going to watch the show Black Spot, so I'll let you know about the method of locomotion.  After my friend told me about the upcoming show, I went to the TV Graphic magazine that comes in my Sunday paper and looked for it.  Sure enough, there was a picture of one of the family members.  It appeared that she was walking on the heel of her hands, but her fingers were kind of sticking up (if you know what I mean).

Since you already saw a show Re: this family of "genetic throwbacks" as the scientist termed them, may I ask you if the family was mentally handicapped?

This sounds like some of the shows I have seen in the past where a child lives and vocalizes in an unhuman manner, but the child has been subject to years of isolation, neglect and abuse.

[The Black Spot]

I'm going by memory here, but I don't know if the family were classed as mentally handicapped or not.Their language skills were poor, but whether that was because they kept themselves isolated from the local townsfolk I don't know. Guess I'll have to look on the BBC archive for a transcript.

[Sibling Spoffish]

Here's a photo:


Looks like they walk on their hands flat, like feet. I too would be interested to find out if they were mentally handicapped.

[Griffin NoName]

This reminds me of the film by Werner Herzog - Enigma of Casper Hauser.  A brilliant film IMHO.

For Goat especially, but for anyone interested more information about Casper Hauser here

It seems that the brain develops certain aspects like language/voice at certain stages and if the appropriate environment is missing at that time of growth/development the chance is missed. I wonder if this relates to walking upright too?

[Vita Curator]

I think that you hit the nail on the head NoName.  I saw a snippet Re: tomorrow night's broadcast of NOVA and the geneticist being interviewed was postulating that this might just be a movement disorder arising from an anomaly in the cerebellum.

It seems that this family had NINETEEN children, and if they were given the opportunity to go through physical therapy, using a walker and parallel bars, it would have helped them enormously. 

It was very sad, watching these adults with this movement disorder.   I will have to leave my final opinion as to whether this is a "genetic throwback" though until after I watch this episode of NOVA.

[The Meromorph]

I must admit, I find it difficult to even consider whether this is a 'genetic throwback', as it seems to me blindingly obvious that it can't possibly be.
Even assuming the modality of locomotion to be 'directly' genetically determined, and dis-linked from the genetics of the physical 'apparatus' of locomotion (muscle size and placement, bone proportions, spine to skull angle, etc.), this modality of locomotion is unrelated to any possible (or even viable - except in a supportive modern [last 10,000 years] environment) modality in the transition of a Primate from partly arboreal to ground dwelling.
Walking with the rear limbs straight when they're twice the length of the forelimbs? Come on! 

[Griffin NoName]

I don't want to detract from a serious discussion by my wretched sense of humour being in overdrive tonight, but following on from Quasi's thoughts...... is it possible that it could be a partial evolutionary throwback - like those legs were still the thrown forward form but other parts weren't?  I think we best wait for Vita to scrutinise this TV programme with great focus on our pressing questions.

I'd be more convinced if they weren't using their hands palm down to the ground - that's the bit that looks odd to me. (ok, Ok, humour me!!)

I hope the programme is sensitive. I worry that this is our modern form of visiting the fairground to see the elephant man. We have an ever increasing number of such programmes here and I'm not sure I am always keen to watch them for the "right" reasons.

[Vita Curator]

Well, in the end, the question of reverse evolution was left unresolved.  The mutation of the responsible gene that controls the regulatory process of upright motion was not identified.

It came out in the program that the parents were cousins, so the children inherited two defective genes. 

Simple neuro checks showed deficits in intellect, language and fine motor skills.  The program showed one of the sons that was not quadrupedal but he ambulated with an ataxic gait (staggering, off balance) and also with a wide base.

Brain CT's were done and read by Roger Keynes, a Cambridge neuroscientist.  On the CT scan the loss of tissue in the cerebellum could be clearly seen.

We are clearly genetically hardwired but cultural influences play such an important role here (the old nature vs. nurture).  This woman had 19 children.  She had 7 children in a time span of five years, and out of these seven children, four were afflicted with this ataxia/quadrupedal ambulation.  Upon questioning, the parents did reveal that these children at ten months of age were doing the bear crawl instead of the standard crawl. 
If these were any of our children, we would have gone to the pediatrician and started on PT, braces, walkers, etc.  Walkers and parallel bars were given to the family by Nicholas Humphrey (one of the researchers) from The London School of Economics, and it showed that after one year, several of the children were using the walkers to walk, and to use the parallel bars for exercise.

As a side note, the discussed the single family in Great Britain where members of three generations had severe difficulty in speaking.  They had a single letter of the DNA code misspelled on the FOXP2 gene on chromosome 7.

The FOXP2 gene has changed in structure only three times.  The sequence of this same FOXP2 gene has been stable in all mammals with the exception of humans where two significant changes occurred in the coding region of the gene as recently as 100,000 years ago.    It is postulated that these changes may have contributed to the development of language in human beings.  Fascinating, no?

[Bob in a quantum-state-of-faith]

  Fascinating, no?

Fascinating, YES!

Thanks for the excellent summary - I did not find time to watch, unfortunately.

It's good, I think, that they are trying to help the other children.

Somewhere I read, that humans, with their great, huge heads, gave up quite a bit of instinctive behaviors (which are more-or-less locked into place) in exchange for culture-based behaviors, which are more flexible.  That is, a young human had few if any survival instincts, and if he is not raised in a human culture, will not likely survive.  A young cheetah, on the other hand, has an instinct for hunting and survival - the cheetah may not be as proficient as one raised by a mother-cheetah, but he would have a good chance of surviving anyway.

Humans gave up instincts for big-brains.  Our "instincts" consist of our social behavior, and we take an inordinate length of time to "ingest" it all-- as compared to other mammals.

But. (and it's a big but) By moving our survival behavior out of the genetic-level of coding, and up into the behavioral one, we became hugely adaptable - indeed, humans have adapted to more and varied environments than any other mammal*.

Cool beans, Vita!


_________________________

*With the possible exception of the lowly rat. However, it should be pointed out, that the rat, in placing it's chief survival portfolio (at least in terms of numbers of individuals committed) in firmly with the humans, shares in the humans' adaptive abilities.  Riding on the humans' coattails, as it were.

One could even say "symbiosis" with humans-- but most would say "parasite".

Me, I think it's somewhere in between parasitic and symbiotic.  Who knows? Some day, we may embrace our ratty cousins, and modify them to actually help us exist in our environments.  Can you imagine a disease-free rat, sneaking around, cleaning up after your meals? One that was trained not to eat the stored provisions, but only clean up the fallen leftovers? And, was trained to leave it's "exhaust" in a sanitary location, instead of behind your cereal boxes.

I can see it now: rat street-cleaners, dragging our tossed garbage over to collection points, living on our discarded foodstuffs and also being a predator on other pesky things, like cockroaches ...

[Opsa]

I saw the show and thought it was very well done. It didn't reach a firm conclusion, but it was quite compassionate.

I didn't think that they were genetic throwbacks. I felt the same way as Quasi, that their legs were much too long and/or their arms too short to be physically characterized as an earlier primate form.

It seemed to be a combination of circumstances that made them walk like that: the cousin-parents, the overwhelmed-with-kids-mom and the poverty. I was tremendously impressed that the scientists tried to help them by giving them a walker and parallel bars for physical therapy, which really seemed to help them by the end. They might have been a bit slow mentally, but they were sharp enough to want to learn how to walk like  other people do.

I had to say I cried a little bit when Hussein (was it?) came around the corner on twos. Very moving.

[Griffin NoName]

I wish I'd seen the programme. I'm glad to hear it was sensitive. Thanks for all the info.

As a side note, the discussed the single family in Great Britain where members of three generations had severe difficulty in speaking.  They had a single letter of the DNA code misspelled on the FOXP2 gene on chromosome 7.

The FOXP2 gene has changed in structure only three times.  The sequence of this same FOXP2 gene has been stable in all mammals with the exception of humans where two significant changes occurred in the coding region of the gene as recently as 100,000 years ago.    It is postulated that these changes may have contributed to the development of language in human beings. 

I'm trying to get my head round this in terms of mistakes in coding and natural selection. I just don't know enough about these things so my head is spinning. But then I'm all mixed up trying to tie Freud and Darwin together at present (essay time).

[Sibling Chatty]

Having been constantly blindsided by the differences that the tiniest change in DNA code can make, one would think that we'd be less astounded by these changes. Only the very bizarre and obvious ones are really studied until there's an outcry to do so.

[Swatopluk]

I am not a geneticist either but there are certain common forms of "throwbacks" called atavisms that usually are dysfunctional because they are useless alone and not in combination with others. Examples are multiple nipples (though not functional ones), primitive gills (not working either) or fur (bearded women are the harmless version but there are also "werewolves" [no bloodlust but thick hair an the whole body]).
The described quadrupedal throwback would be uncommon (because only affecting the brain) but would fit into the usual "useless if not combined with..." pattern.
The distinction might be that "common" atavisms are not mutations in the normal sense but the reactivation of unused genetic code we all still carry with us. The described case looks more like a point mutation at a critical position.
That's just my 2 cents to the discussion (not having seen the docu, I deliberately do not own a TV set).

[Sibling Chatty]

There's a kid at MD Anderson that has neurofibromatosis and the werewolf thing going on at the same time. He was being kept at home in his remote village somewhere in eastern Europe, with a mostly blind grandmother taking care of him.

A doc from Doctors Without Borders found out about him when they were doing inoculations in the region. They brought him to Houston 5 years ago. He's learned English (no accent) and is 12 years old, doing math and science on a beginning college level, and is high school level in all other school courses, plus had learned to play 7 musical instruments.

He doesn't want publicity. Can't blame him. But there's a wealthy individual that's paying a fortune for electrolysis for this kid...and he hopes to someday be able to attend college full time. (Rice University, across the street from the Medical Center, will take him at any time. Rice is very difficult to get into.) Having done gift and toy deliveries to MDA for a number of years (and being a neurofibro patient myself) i've met this kid. He's just a sweet, normal kid who loves Halloween, because he can pretend to be "acceptable" normal for a little while.

[Sibling Kephra (Tansy)]

I have a tail.  No joke.  My spinal cord is 2 vertebrae 'too long'. 
It isn't noticeable unless I bend over, and even then it's 'tucked under' a bit.  School was fun with those hard metal chairs attatched to the desks.  Many a bruised tailbone...  lol
An ex liked to joke alot about 'getting a piece of tail'... 

[Sibling Chatty]

Mine's one short. Too bad a transfer would be messy, expensive and no help to either of us.

[Sibling Kephra (Tansy)]

lol... hey...  wonder if I could 'sting' people....

[The Meromorph]

I have a tail.  No joke.  My spinal cord is 2 vertebrae 'too long'. 
It isn't noticeable unless I bend over, and even then it's 'tucked under' a bit.  School was fun with those hard metal chairs attatched to the desks.  Many a bruised tailbone...  lol
An ex liked to joke alot about 'getting a piece of tail'... 

Between four to seven weeks of foetal development, all humans have a tail. It is later reabsorbed. Not only that, but we share with mice (in whose genome they've been found) the same tail-making genes. It appears that there is a separate mechanism controlling the tail's apoptosis*, so that the occasional human born with a tail isn't like that because of the reactivation of old genes, but rather because the genes to remove it have malfunctioned.

Thought you might be interested.


*Apoptosis is a process in the development of an embryo which involves programmed cell death. Cells are formed... only to be destroyed.

[Sibling Kephra (Tansy)]

Nifty!

I malfunction...  I *knew* I had an excuse there somewhere! 

[Swatopluk]

You should have protested within the 9-month guarantee time
I hope there are no protusions on your head too or we could get a nasty suspicion

[Sibling Kephra (Tansy)]

No... nothing other than the piercings. 
I figure the Powers That Be thought I was innately 'evil' enough.  Nothing really needs to be announced there...
Believe me; the offspring are proof enough.