While most of the items in the ballot have been the subject of
considerable discussion in the Chlamydomonas Newsgroup, little has been said
about item 6 -- use of the double colon and the inserting DNA to indicate an
insertion. I am opposed to this for two reasons:
1) In Chlamydomonas, insertions are often messy. For example, an
insertion resulting from transformation with pMN24 DNA (consisting of NIT1 in
the pUC119 plasmid) may retain only a portion of the original sequence.
Following selection, this is usually the NIT1 sequence with all, part, or none
of the pUC sequence, but we have obtained insertional mutants in which at
least part of the NIT1 sequence has been lost. These mutants also may have
large deletions at the site of insertion. In any case, there is no simple and
straightforward way of designating what is included in such mutants.
2) The nomenclature is cumbersome and unwieldy.
Since the nature of the insertion would be given in the initial
description of the allele (each insertional mutant should be given a different
allele number) and would normally be reviewed in the Introduction of any
subsequent paper in which the mutant was used, I do not see any pressing need
for attaching so much baggage to the allele designation. Perhaps the use of
the double colon and inserting DNA could be left optional, but I would not
want to see it required for publication or entry of mutant strains into data
bases.
