Chronic lymphocytic leukaemia (CLL) is the most common form of adult leukaemia and is characterized by a highly variable clinical course. CLL is essentially divided into indolent (stable) and aggressive forms. Little is known about the molecular correlates underlying different CLL disease patterns that are clinically evident. Among the strongest predictors of outcome is the disease –associated chromosome abnormalities, with 17p and 11q deletion and trisomy 12 associated with more aggressive disease, while 13q deletion (incidence 50-60%) is the lower risk according to Dohner’s cytogenetic classification. More recently, with the advent of whole genome sequencing (WGS) and whole exome sequencing (WES), nearly 50 recurrent coding gene mutations (driver mutations) have been identified that are associated with higher risk cytogenetic abnormalities and are less commonly seen in lower risk cytogenetic abnormalities (indolent form). In fact, very little is known about the genetic abnormalities in indolent CLL. Since the indolent CLL patients live a disease free longer life (10–20 years), not many changes in the genomic sequences are normally predicted during the disease free time. So far, no longitudinal genomic studies have been done on indolent CLL patients. In this study, we attempted longitudinal genomic studies on 10 indolent CLL patients. We isolated pure CLL cells from two time point (3 to 6 years apart) samples of each patient and then did comparative whole genome sequencing and SNP array analysis on paired samples. Results will be discussed at the presentation.