Essentials of Genetics 9th Edition by Michael Palladino William Klug, Michael Cummings, Charlotte Spencer

Exercise 8

The locations of numerous lacI ? and lacI S mutations have been determined within the DNA sequence of the lacI gene. Among these, lacI ? mutations were found to occur in the 5?-upstream region of the gene, while lacI S mutations were found to occur farther downstream in the gene. Are the locations of the two types of mutations within the gene consistent with what is known about the function of the repressor that is the product of the lacI gene?