We used the Ongen et al., 2017 methodology to detect regulatory drivers in tumour development. This method starts by discovering cis regulatory domains (CRDs) and tests to see which of them accumulate an excess of somatic mutations. Some significant genes discovered had altered allelic imbalance when comparing to non significant CRDs indicative that allele specific expression can be used as a proxy to discovering somatic mutations, something already shown by Ongen et al., 2014. Since we had unmatched samples, we had to come up with a novel methodology to discover regulatory drivers using ASE as a proxy to somatic mutations. However, due to the small sample size, we could not detect any significant genes under selection in CLL but showed that the methodology has potential. Overall, the approaches presented in this study can be generalized to multiple cancers, providing the opportunity to learn about the understudied non-coding regulatory drivers.