The current proposal requests funds for the purchase of Illumina HiSeq 2500 sequencer, a next- generation, massively parallel sequencing platform. The ultra-high throughput of Illumina instruments, coupled with substantially reduced sequencing costs have made this a platform of choice for interrogating regulatory genomic sequences and function. Massively parallel sequencing is particularly well-suited for epigenomic and functional genomic studies, including chromatin structure, Chromatin accessibility, histone modifications and variants, regulatory factor localization;DNA methylation;transcription;and quantification of genome modifications such as localization of retroviral vector integrations. HiSeq2500 sequencer has dual flow cells with high density clusters generated in each channel that produces high quality passing filter data of 600 GB per 2X100 bp run. The two flow cells can be operated independently using different chemistries. The sequencer has the capability to operate in dual mode;in rapid run mode the clusters are generated on the sequencer, allows producing up to single or paired end 150 base long reads, and run times are several fold shorter , while in high output mode the sequence yields are up to 600 Gb per run. This allows tailoring the sequence run to the desired outcome in terms of speed vs. significantly large data output. The advances in Illumina sequencing technologies and chemistries, the price per Mb sequence output has made HiSeq a platform of choice for functional genomics research, These advances have led to explosive growth in demand for massively parallel sequencing, as more investigators realize the potential of the technology to impact and accelerate their research. The new instrument will be deployed in the context of a well-established, self-supporting core facility that already provides substantial epigenomics-focused next-generation sequencing services and associated bioinformatics support, and is therefore ideally positioned to rapidly translate the HiSeq 2500 potential to meet the needs of specific investigator projects as well as those of the general research community.