(Fwd) Re: Genetics (fwd)
- Subject: (Fwd) Re: Genetics (fwd)
- From: j*@redrose.net
- Date: Tue, 20 Feb 96 19:36:36 MST
------- Forwarded Message Follows -------
Date: Tue, 20 Feb 96 18:10:16 MST
Reply-to: iris-l@Rt66.com
From: Sue Madison <smadison@comp.uark.edu>
To: Multiple recipients of list <iris-l@Rt66.com>
Subject: Re: Genetics (fwd)
Below is message from my son at WASH Univ. with info on questions we have
had about maternal influence on heredity. Sue
---------- Forwarded message ----------
Date: Tue, 20 Feb 1996 13:01:56 -0600 (GMT-0600)
From: Blair Madison <bbmadiso@artsci.wustl.edu>
To: Sue Madison <smadison@comp.uark.edu>
Subject: Re: Genetics
It is true that mitochondria and choloroplasts contain circular pieces of
DNA. This DNA mainly functions to create proteins used within the
mitochondria or chloroplasts for internal function or replication, and
the pathway of proteins appear "to be unidirectional, inasmuch as no
protein is known to be exported from mitochondria or chloroplasts to the
cytosol." [Molecular Biology of the Cell 2nd ed. Garland Publishing: New
York, London, 1989] So parental female haploid cells should have no
effect of passing on more traits to filial generations than the male
haploids. If traits were somehow sex-linked there may be some correlation
between female traits and filial traits but I'm not exactly sure how this
may work. I'll let you know if I find anything else.
Note_
I do not agree that non-nuclear DNA is not expressed outside of the
phenotype. Male-sterility is maternally and extranuclearly inherited
in maize, as is the susceptibility t-cytoplasm confers for Southern
Corn Leaf Blight.
In what I said previously, however, I think that it may be more in
animals that any significant amount of non-nuclear DNA
(mitochondrial) is transmitted. I think by the time the pollen tubes
grow down, any cytoplasm in that tiny cell has been spread out fairly
thinly.
Steve Brown
J. Steven Brown Mt. Gretna Gardens
Genetic Consultant
Iris and Daylilies:
Breeding and Production
2493 Pinch Road
Manheim, PA 17545-9466
USA Internet:jsbrown@redrose.net
(717) 664-5080 Homepage:"http://www.success.net/
mggarden/"
fax 5081
