This work is related to the characterization of the Chl1 protein of the budding yeast Saccharomyces cerevisiae. A null mutant lacking this protein is affected in several functions of yeast such as sister-chromatid cohesion, rDNA recombination, lifespan, stress response, transcriptional silencing and DNA damage repair. It is not clear whether the protein has several domains for these diverse functions or the loss of one underlying function leads to the loss of all. This book deals with the series of experimentations done to phenotypically characterize the mutation in Chl1 gene.