MOLECULAR ANALYSIS OF SEVERAL MUTANT DERI VATIVES OF THE UNSTABLE WHITE-STARKA ALLELE

Molecular analysis of several mutations of the white locus was perform ed. The mutations were obtained as a result df mutagenesis in the unst able white-starka locus described previously. A large insert (approxim ately 15 kb in length) downstream of the first exon of the white gene was shown to be partly excised. Simultaneous excisions of various regi ons from the natural regulatory region of the white locus were also ob served. Restriction enzyme analysis showed that the observed mutations and reversions resulted from large deletions from the regulatory gene region. Southern and Northern blot hybridization showed the presence of unknown regulatory regions within and outside the insert.