What is a gene?

[Przemko]

some deletions

>>      No less vexing, to me, is the question "what is a gene?" and how
>>to teach *that* body of ideas and data. This is a question that, both
>>from my own experience & from rumors I've heard over the years, can
>>blow away even a Ph.D.-candidacy-exam student because it seems so simple.
>>
>>      Any thoughts on the matter?
>>
>>
>>-- 
>>Mark D. Garfinkel (e-mail: garfinkl at iitmax.acc.iit.edu)
>>My views are my own, which is why they're copyright 1994
>
>
>How about: 
>
>         A gene is a segment of DNA/RNA that, when
>transcribed/reverse-transcribed, 
>               leads to a biologically functional product.
>
>This covers genes that code for proteins, genes that code for nucleic
>acids (e.g: tRNA genes), and retroviral genes.
>
>Comments?
>
>Ron Kagan
>rkagan at ewald.mbi.ucla.edu

Well, what if the function of a gene is not known and therefore we cannot say
that it codes for a biologically active product. Specifically, let's say
you sequence a piece od genomic DNA, do some magic to find exons and then
what. Do you have a gene or a virtual gene or a potential gene?
Along the same lines I have posted about a year ago a question about gene
locus: what it is- a place on chromosome, and could a few bases define
a locus. The answers I got were rather unsatisfactory. Anyway, many of these
definitions are, unfortunately, more intuitive than anything else.

My 2c

Przemko