Posted by:
boxienuts
at Fri Jul 25 10:45:04 2008 [ Email Message ] [ Show All Posts by boxienuts ]
If you have only one mutant allele or variation of a gene other than the wild type, then yes the characterizations of dominant, co-dominant and recessive are only relating that variants relationship to the wild type, however if you have multiple alleles at the same loci (or gene or set of genes) then those terms are used to characterize the relationship or how they relate to one another. So example if you have alleles A,B,C,D; A could be dominant to B but B is recessive to C, but A is co-dominant with D which is the wild type. These terms are generally used to characterize what is going on at the genotypical level, based on the visual evidence of the phenotype displayed, but sometimes when looked at on a DNA sequence(genomic) and protein sythethis level it is not that simple, but that is a whole "nother" can of worms and it can get very complicated with regards to what is influencing what. That is why a recessive trait with linebreeding as well(ex. sunglow or bloodred), when outcrossing or hets are produced, may or may not carry the line bred characteristics with that trait. Because line bred traits are usually the result of a set of many different blended genes selected to give the resulting phenotype over several generations, rather than a simple on/off switch of one gene or set of genes, the latter being more desireable for the snake breeder to work with because it's easier to control and predict the outcomes.
Sorry so long, hope that makes some sense ----- Jeff Benfer
1.0 pastel Python regius
1.1 mojave Python regius
0.1 normal Python regius
1.3 Terrapene carolina thriunguis
2.3 Terrapene carolina carolina
4.1 Kinosternon baurii
1.1 Malaclemys terrapin terrapin
2.2 double het albino and anerythristicThamnophis sirtalis parietalis
1.0 anerythristic Thamnophis sirtalis parietalis
2.2 Iowa snow Thamnophis radix
0.2 het Christmas albino Thamnophis radix
1.1 double het cherry erythristic, albino Thamnophis sirtalis sirtalis
1.1 melanistic Thamnophis sirtalis sirtalis
1.1 triple heterozygous for amelanistic,carmel, and stripe Pantherophis guttatus
0.1 anerythristic motley Pantherophis guttatus
0.1 Okeetee Pantherophis guttatus
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