Re: [asa] lactose tolerance mutation PS

From: Robert Schneider <rjschn39@bellsouth.net>
Date: Tue Dec 12 2006 - 23:17:50 EST

Responding to Randy's note as well as these, I believe that it is a common
assertion among evolutionary biologists that most mutations are adaptively
neutral, the second largest are harmful, but there are some that are
beneficial. So, if this is correct, I'm puzzlied that Nelson would assert
that there are no beneficial mutations--unless he is asserting YEC dogma: no
beneficial mutations, no evolution.

Bob

----- Original Message -----
From: "Don Nield" <d.nield@auckland.ac.nz>
To: "Don Nield" <d.nield@auckland.ac.nz>
Cc: "Jim Armstrong" <jarmstro@qwest.net>; <asa@calvin.edu>
Sent: Tuesday, December 12, 2006 8:57 PM
Subject: Re: [asa] lactose tolerance mutation PS

> PS: I meant a*certain* enzyme! I also leant from the link in Jack's blog
> that there was one European mutation that had the same effect as each of
> the three African mutations, -- a good example of multiple convergent
> evolution.
> Don
>
>
> Don Nield wrote:
>
>> Reading the article from Jim's link I learnt that it was three mutations
>> in one population -- and an unspecified number in another population --
>> having an equivalent effect -- keeping a cratin enzyme active.
>> Don
>>
>> Jim Armstrong wrote:
>>
>>> It sure sounds like the same or an equivalent mutation. This from the
>>> Washington Post article
>>> <http://www.washingtonpost.com/wp-dyn/content/article/2006/12/10/AR2006121000781.html>
>>> :
>>>
>>> "Now, researchers have evidence that the domestication of cattle
>>> thousands of years ago was the key to lactose tolerance emerging
>>> independently in Europe and Africa."
>>>
>>> The easiest explanation is the same mutation. One might speculate about
>>> a certain susceptibility that allowed one mutation to occur, also
>>> allowing the same mutation under similar conditions in another location.
>>>
>>> JimA
>>>
>>> Randy Isaac wrote:
>>>
>>>> This afternoon I listened to the radio program "The Bible Answer Man"
>>>> sponsored by the Christian Research Institute. Paul Nelson was the
>>>> guest. He is very impressive in his style of communication. It was
>>>> generally the standard ID fare but I was surprised at his answer to one
>>>> of the call-in questions. The caller asked whether there were any
>>>> beneficial mutations or if they were all harmful. Paul essentially said
>>>> none was beneficial and mutations may be neutral at best but neutrality
>>>> doesn't drive evolution.
>>>> I wish I could have jumped in and asked about the article that Jack
>>>> Haas posted on his blog on Dec. 11 (I presume you all regularly check
>>>> Jack's blog at http://www.asa3.org/weblog/jackhaas/ ) on lactose
>>>> tolerance. If I understand it correctly this is not only an example of
>>>> a positive mutation (assuming it is positive to be tolerant of lactose)
>>>> but also one of convergent evolution. I'm not an expert in this field
>>>> so I have some questions for those of you who are. Are they implying
>>>> that the same mutation occurred in different populations to achieve
>>>> convergence in lactose tolerance? Or are these different mutations? If
>>>> so, what are the characteristics of the mutations causing this change?
>>>> Is it silencing a specific protein? Activating a silent one? In
>>>> general, I would like to know what you think is the significance of
>>>> this finding.
>>>> Randy
>>>
>>>
>>
>>
>
>
> --
>
> Donald A. Nield
> Associate Professor, Department of Engineering Science
> University of Auckland
> Private Bag 92019
> Auckland 1142, NEW ZEALAND
> ph +64 9 3737599 x87908 fax +64 9 3737468
> Courier address: 70 Symonds Street, Room 235 or 305
> d.nield@auckland.ac.nz
> http://www.esc.auckland.ac.nz/People/Staff/dnie003/
>
>
> To unsubscribe, send a message to majordomo@calvin.edu with
> "unsubscribe asa" (no quotes) as the body of the message.
>

To unsubscribe, send a message to majordomo@calvin.edu with
"unsubscribe asa" (no quotes) as the body of the message.
Received on Tue Dec 12 23:18:30 2006

This archive was generated by hypermail 2.1.8 : Tue Dec 12 2006 - 23:18:30 EST