The symbolic representation of many different genes can sometimes become confusing. Early on, geneticists adopted the format of representing different alleles by the same letters. This procedure is somewhat confusing because quite often the letters represent conditions totally unlike the terms or trends implied by the letters themselves. On the right, different mutations common to work with Drosophila are listed along with their symbols and the normal allele for the mutation. Note the somewhat awkward expressions for a normal wing or eye color when they have to be represented by Vg or Bn. Note also that Bar eye as the mutation is dominant with the normal allele thus represented by the lower case b. Some of the confusion can be cleaned up by simply representing all the normal alleles, regardless of the gene they belong to, with a + symbol. Click on the + button to achieve this.
