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how do mutations have no effect if it's on a non coding region of DNA

How would a mutation not cause change to an organism if it's in a non coding region of the DNA? Don't non-coding regions of DNA have regulatory functions? Or do some regions of DNA have no function?
Multiple bases can code for the same amino acids so the base can change without changing the protein the overal gene codes for. Does that help?
Precisely it. Some regions of DNA are pretty redundant. 'Filler' if you will. I don't know of you've covered how mRNA is made in detail but basically 1 DNA strand is copied. Of this copy only some sequences of bases will make it into mature mRNA (called introns) while the rest if left out (called exons). Because only intron sequences are used in protein production mutations in exons will not effect the protein product for sure.


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Original post by Jacob :)
Multiple bases can code for the same amino acids so the base can change without changing the protein the overal gene codes for. Does that help?


That's a 'silent mutation' and does not relate to noncoding DNA mutations as it'd be in the coding region


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Original post by Eljamaispa
Precisely it. Some regions of DNA are pretty redundant. 'Filler' if you will. I don't know of you've covered how mRNA is made in detail but basically 1 DNA strand is copied. Of this copy only some sequences of bases will make it into mature mRNA (called introns) while the rest if left out (called exons). Because only intron sequences are used in protein production mutations in exons will not effect the protein product for sure.


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Other way around: introns are chopped out; exons are kept.

You're exactly right, though. There is a certain amount of 'junk' DNA, although nowhere near as much as we used to think. A lot of scientists even think a lot of junk DNA has a function, but we just haven't found it yet. But on top of this, functional non-coding sequences are more tolerant to mutations than coding DNA is - they have more "flexibility" in what'll still allow them to function, if you prefer.

Original post by Jacob :)
Multiple bases can code for the same amino acids so the base can change without changing the protein the overal gene codes for. Does that help?


That answers the exact opposite of her question. :tongue:
Original post by Hype en Ecosse
Other way around: introns are chopped out; exons are kept.

You're exactly right, though. There is a certain amount of 'junk' DNA, although nowhere near as much as we used to think. A lot of scientists even think a lot of junk DNA has a function, but we just haven't found it yet. But on top of this, functional non-coding sequences are more tolerant to mutations than coding DNA is - they have more "flexibility" in what'll still allow them to function, if you prefer.



That answers the exact opposite of her question. :tongue:


Haha! Sorry! It's been two years since I touched genetics. I'll have to go back over it. I always found it interesting.
Reply 6
Original post by Hype en Ecosse
Other way around: introns are chopped out; exons are kept.

You're exactly right, though. There is a certain amount of 'junk' DNA, although nowhere near as much as we used to think. A lot of scientists even think a lot of junk DNA has a function, but we just haven't found it yet. But on top of this, functional non-coding sequences are more tolerant to mutations than coding DNA is - they have more "flexibility" in what'll still allow them to function, if you prefer.



That answers the exact opposite of her question. :tongue:


From what i was reading, it seemed that we had nearly 53% junk dna. Not sure if i remember that correct.:biggrin:

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Original post by Eljamaispa
Precisely it. Some regions of DNA are pretty redundant. 'Filler' if you will. I don't know of you've covered how mRNA is made in detail but basically 1 DNA strand is copied. Of this copy only some sequences of bases will make it into mature mRNA (called introns) while the rest if left out (called exons). Because only intron sequences are used in protein production mutations in exons will not effect the protein product for sure.


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Original post by Hype en Ecosse
Other way around: introns are chopped out; exons are kept.

You're exactly right, though. There is a certain amount of 'junk' DNA, although nowhere near as much as we used to think. A lot of scientists even think a lot of junk DNA has a function, but we just haven't found it yet. But on top of this, functional non-coding sequences are more tolerant to mutations than coding DNA is - they have more "flexibility" in what'll still allow them to function, if you prefer.



That answers the exact opposite of her question. :tongue:



Original post by Dynamo123
From what i was reading, it seemed that we had nearly 53% junk dna. Not sure if i remember that correct.:biggrin:

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Oh so non-coding regions of DNA don't have a function? But we're non exactly sure of that as we have to investigate more?
Original post by celina10
Oh so non-coding regions of DNA don't have a function? But we're non exactly sure of that as we have to investigate more?


Yep


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Reply 9
Original post by celina10
Oh so non-coding regions of DNA don't have a function? But we're non exactly sure of that as we have to investigate more?


Exactly. There is some research going on, but so far, its mum:biggrin:

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Original post by celina10
Oh so non-coding regions of DNA don't have a function? But we're non exactly sure of that as we have to investigate more?


NO. NO. NO.

Many non-coding regions do have functions; some do not. Of the ones that do not have a function, they might have a function that we haven't found yet.

There's a list of functions here.

Non-coding DNA isn't one homogenous entity. Lots of different parts have lots of different functions - some don't have any function at all. We can't talk about "non-coding DNA" as if it's all the same thing.

Original post by Dynamo123
From what i was reading, it seemed that we had nearly 53% junk dna. Not sure if i remember that correct.:biggrin:

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The ENCODE project suggests that >80% of our DNA is functional.
(edited 10 years ago)
Original post by Hype en Ecosse
NO. NO. NO.

Many non-coding regions do have functions; some do not. Of the ones that do not have a function, they might have a function that we haven't found yet.

There's a list of functions here.

Non-coding DNA isn't one homogenous entity. Lots of different parts have lots of different functions - some don't have any function at all. We can't talk about "non-coding DNA" as if it's all the same thing.

The ENCODE project suggests that >80% of our DNA is functional.


Oh right I see. Can I ask you one more question?

For the lac operon, what are the regulatory sequences? Is it just the operator and promoter region, or is the regulatory gene part of the regulatory sequences?
(edited 10 years ago)
Reply 12
Original post by Hype en Ecosse
NO. NO. NO.

Many non-coding regions do have functions; some do not. Of the ones that do not have a function, they might have a function that we haven't found yet.

There's a list of functions here.

Non-coding DNA isn't one homogenous entity. Lots of different parts have lots of different functions - some don't have any function at all. We can't talk about "non-coding DNA" as if it's all the same thing.



The ENCODE project suggests that >80% of our DNA is functional.


Got ir opposite then :facepalm:

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