I had a discussion recently with someone regarding the merle gene which went wider into genes and heritability generally, we got into diabetes, homosexuality, blue eyes, the works .They said genes could be turned on and off. I said initially that was rubbish, a gene was either present or not.

I looked into it and found this http://en.wikipedia.org/wiki/Gene_regulationHere it says it occurs at the cellular level, what are the implications? What is the end result of a change in a gene at the cellular level? Ha, someone may also be kind enough to tell me how to hyperlink properly to this site.

Can some of you brainiacs out there explain what this means. Can for example the diabetes gene be switched off? Can the merle gene be switched off? Can someone explain in laymans language how this occurs, or link me to an article. I hate to loose an argument, but if I have to I'd at least like to know why. Is it all kinds of genes, why? etc etc.

Thanks folks!

I think we might need a geneticist to explain that article to us, it's beyond me.

I have thought of genes being turned on and off in terms of the controls on when the lifespan genes work. Like the genes that control head shape in dogs, where the growth of different areas' of the skull is switched off at different times so that the range of different shapes are possible. But other than that, I don't know.

I believe it is at the singular level cells of genes that can be turned on and off. The one that I understand is when we have a wound, the genes or to be more correct the cells turn on to fight the intruders, then another level of cells are switched on to repair the wound. It is the same with our hormones. So I think only certain cells can be turned on and off. What were you specifically talking about, DNA and our genetic make up is that different to our single cells or is it all incorporated into one?

We were talking about how behaviors in particular can be caused by a gene/genes. The other person said that genes can be turned on and off. Using the examples of the merle gene and diabetes. I said that the merle gene is not turned off or on, it is simply present or not, and once present the obvious would follow in the physical appearance of the dog, that even at the stage of the cells splitting after conception, the gene stays put and manifests its affect at birth. I said that the type 2 diabetes gene is the same except you can lower your risk by consciously modifying your eating behavior (I guess employing your behavioral gene for self discipline...which is not a question of on/off but of employing what is already there. The other person then said that in homosexuals (I guess because he thinks it must be genetic) that the gene can be turned off. I said no, that all that would occur is behavior change, ie not acting on the urges, which is a bit like the diabetes example but like diabetes would not change the fact someone is gay. Then they went on and on, they are a bit of a religious nut. Hard to get them to think straight!Thank you for the above....I hate to loose! I guess this is all helpful info in a way for serious dog people because even though a dog may be predisposed to a certain thing...well the classic is scavenging fat Lab's LOL, the dog can be trained to not scavenge from tables...well maybe not in the case of most labs I've met he he.... But say a Koolie who comes from a strong line of Cattle workers and who naturally is a hard dog on stock. If the dog is trained early, and not shown bad examples, to take it easier, but that dog must also be genetically predisposed to good bidability.The new behavior will also have to be reinforced from time to time.

Well I can say with homosexuality it is pre-disposed at birth, and it is to do with the X and Y chromosomes. More importantly it is to do with the X chromosome which is passed down from the mother. This cannot be changed by singular cells and cannot be turned on/off otherwise we could change from boy to girl if that was the case. Don't you love people that have strong beliefs and will generally not hear what other people have to say unless it is in line with what they believe in.

Yeah, I've heard something similar. You wouldn't be able to link me to an article about that would you. Geez I hate God Botherers.

Here is a link

X Chromosome findings

Last copyright was 2004, but the report was done in 1995. Yep can understand your thoughts my two girls tend to keep them away from the front door, my OH encourages them too (the dogs not the door knockers). They came past yesterday and the girls were barking my OH went outside and told the dogs quite loudly "Good dogs", the door knockers heard him then went across the street eyeing our dogs quite suspiciously.

None so blind as those that cannot see! Diabetes 1 - autoimmune disease - genetically predisposed. I think there is still a long way to go before we can actually turn off genes. If only it were that simple! From what I've read esp in regard to autoimmune disease there is sometimes a trigger that "turns it on" eg a virus but that is still yet to be confirmed. However there is suggestion that the infestation of parasites may help with autoimmune diseases. Experiments are being carried out in the next 12 months with regard to hookworm and Coeliac Disease.

http://en.wikipedia.org/wiki/Autoimmunity

OK, speaking of the Y and X chomosone, where does the Merle gene sit, if it sits on either?

Not on either, I think. If it was on Y or X I'm sure it would have sex-linked inheritance.

This is the closest to a quotable quote about it's location I could find in the articles I have about it - 'A short interspersed element insertion at the boundary of intron10/exon 11 was found, and this insertion segregates with the merle phenotype in multiple breeds.' (They are talking about SILV or Pmel17 which is the merle gene). I don't know enough about it to know where intron 10/exon 11 is.


Interesting - a bit like the cats/asthma link.

up until my girl was diagnosed with her autoimmune condition, she hadn't been sick a day in her life, the same with her mom, our recently departed Dot, healthy then, bang! pancreatitis and renal failure.
Our vet said we would never be able to discover the trigger which set Titch off.
She has made a full recovery and is off all medication, but we know it can simply choose to re-activate, so she will be regularly monitored.

Yeah, true. Cheers

My understanding is that some genes can be present but not active until triggered by something. This isn't genes for colour or coat pattern as merle is, one example I remember was anorexia where it sits dormant until enough stress or triggers happen to 'wake it up' so this could be similar to families having a tendancy to problems such as diabetes which might be a similar gene.
Merle isn't a sex linked gene but is referred to as partially dominant which creates the merle effect - it isn't active in the solid parts of the dog but is where the colour is reduced.
We recently met up with a "born again" who somehow (not through our efforts) got to gay bashing, after he had gone on about being such a good christian I shut him up by asking doesn't God preach tolerance so shouldn't you leave them alone. He had a really stunned look on his face and I found it very hard not to laugh.

I didn't know about that with anorexia, learn something new everyday. So it is termed as a disease is it? Or is the brain and the gene linked somehow? I wonder if it is the same with Bipolar and sychzophrenia (not sure on spelling)? We certainly get onto some varied discussions in here don't we!

Well, look at depression caused by excessive seratonin reuptake. There is a much greater prevalence of depression around nowdays. I believe modern life has switched it on, ie less excercise, more complex choices etc. I spoke last night with a psychologist who also studied genetics before she did her psych quals. I raised the hereditability of anorexia with her. She said it may have always been around, but under reported. I said that it was highly likely that anorexia in particular would likely to be reported even a hundred or fifty years ago because of the obvious physical symptom of radical weight loss, which general doctors would have picked up, and there doesn't seem to be reported anywhere a plague of very skinny young women in the western world last century. She actually agreed with me on that, and said it probably was a more modern phenomenon, say since the mid 1970's, and plateauing out in the mid 90's.

Yes our lifestyle has become more complicated due to society and what it dictates to us. 24/7 lifestyle, which is not healthy. Pressures that are on us are becoming greater. And everyone seems to be hurried and worried about small things. The media and advertising gurus saying what we should buy, what lifestyle we could achieve, how to improve ourselves by buying "stuff", instead of being satisfied by what we have. People have forgotten how to get joy from the little things in life, a beautiful sunny day, a walk on the beach and to concentrate on the feel of the sand between the toes, taking a deep breath and smelling the gum trees in flower, enjoying the embrace of your loved one and being in the moment. 24/7 living is not healthy and we need time out for ourselves to recharge the batteries. Depression is coming more common and so is bipolar, anorexia is prevalent amongst teens due to outside pressures too, it is one part of their world that they can control as they feel they have no control. And in part I think this is also a problem with alcohol and why it is popular, people forget about pressures when they are drunk. Society can bring people together but it can also tear them down, a very two edged sword.

Okay I shall get off my soapbox now. Sorry about that my brain gets away with my fingers on the keyboard.

Hi All,

I will try to explain what I think you are after.

I believe that the term to turn on or off a gene simply means that it is not apparent in the present state.

let me explain if you breed breed a dog with a defective gene to its daughter you in fact double the defective gene and it becomes dominant.

if you breed a dog with a defective gene with a dog without the defective gene some of the progeny will not show the defective gene as it will be dominated by another.

I dont think that a gene is turned off as much as it is dominated by another,
it won't disappear but will lay dormant until it is doubled or increases in intensity and again becomes dominant.

I have used this principle recently to supress a defective gene in a dog by using a dog that had a similar good gene to the problem dog so that this was doubled and the defective gene was supressed and didn't appear in the progeny.

The trick then is to ensure that the defective gene doesn't again become dominant by increasing it's intensity by introducing the same or similar gene again.

A good example of this is when you breed 2 dogs with full tails together and have in the litter some stumpt tailed pup's.
It would probably then be the case that one or both the dogs had stumpy tailed cattle dogs in their history and by combining the 2 gene sets so doubling the stumpy tail gene.

Another good example is breeding 2 dogs with green eyes and getting Wall/Blue eyes in the progeny. I believe that this happens because both dogs have the Wall/Blue eye gene but have it depressed but when the 2 dogs are mated the gene doubles and becomes dominant in some pup's.
I think that if you want Wall/Blue eye you will have a far greater chance if you were to use a green eyed dog and a brown eyed dog.
This should if both dogs have Wall/Blue eye in their history cause a doubling of the Wall/Blue eye only as the brown and green eye genes would remain singular and there you have it in a nut shell.

When speaking to the registrar about my current litter I said that I expected to get red merles some mainly solids and some with Wall/Blue eye. I predicted this as I was using 1 green eyed dog and 1 brown eyed dog both with Wall/Blue eye in their histories.

So you see that the genes can't be turned off as this wouldn't have happened but merely depressed compared to other genes that were at the time dominant.

Gene therapy is done along the same lines by malipulating 1 gene so it becomes dominant and overrides the faulty gene.

you then need to take in consideration that both gene manipulation and things such as enviromental influences can have an effect on a gene at the cellular level.
I hope that this makes sense to all as I don't think I can put it any simpler

Jack @ Wilja Koolies

To All,

For those interested I will try to explain in simple terms what cellular genetics is about.

The first thing you need to know is that all things are made up of atoms, Us our dogs our houses the water that we drink etc.

The atom's structure determines what the atom is whether it be steel or flesh water or anything else.

the way that this is determined is in the structure of the atom itself.
The atom consists of a nucleas and an amount of rings around the nucleus called VALENCE SHELLS.

These Valence shells are like rings around the nucleus and can be many in number.

These Valence shells have different numbers of electrons in them which determines what the atom is.

I will give examples in a simple way but not using actual numbers to simplify.

Say an atom to make steel has 4 electrons in the 5th valence shell and brass has 6 electrons in the 5th valence shell. This would mean that if something were to change the 5th Valence shell from 4 to 6 electrons the atom will change from steel to brass.

Say an atom making up eye color has 2 electrons in the 7th valence shell for brown and 4 electrons for green and 6 electrons for blue. this would mean that by changing the electron count in the 7th valence shell would change the
atom from one color to another.

when something is bred the atoms from both mix and you may have additive or subtractive combination in the electrons in the atom.

Once you then understand that an atom can have a different electron count in several different valence shells you will start to understand the complexity the geneticists have to work with.

You must also understand that us, our dogs a house brick etc are made up of Millions of these atoms.

this is called ATOMIC THEORY. the basis of everything.

Jack @ Wilja Koolies

The Question at the beginning of this post concerns the Cellular level.
The Atomic level is a level below the Cellular level.
In other words a cell is made up of a large number of Atoms.
It is impossible to change an Atom without it degrading.
Today’s technology does not allow us to effect the Atom on a minor level, such as eye colour.
If you were able to change the Atoms in a dog today the resulting outcome would be gloop.
There for we are restricted to influencing that which we can, which is found on the Cellular level, namely DNA!!

Recessive Genes can be suppressed through breeding clear to clear (non carrier) but without a DNA screen test to identify your carriers from non carriers it is impossible to just select.
A recessive gene will always be recessive it can never be doubled up, nor can it become dominant.

It can remain dormant for decades of generations then re-emerge, the only way to keep a recessive gene dormant it through the use of a DNA screen test which will identify the gene, so carriers can be bred to non carriers.