Next Generation DNA Sequencing

DNA-SEQ is working with state-of-the-art, Next Generation Sequencing (NGS) partners using the broadest offering of leading sequencing platforms that are CLIA certified and GLP compliant.

Next Generation Sequencing (NGS) of patient DNA is emerging as an important additional source of information for Oncologists to make treatment decisions.  

DNA sequencing is the process of determining the precise order of nucleotides within a DNA molecule; it determines the order of the four bases - A (adenine), G (guanine0, C (cytosine), and T (thymine) in a strand of DNA. 

Cancer genome sequencing is the sequencing of a single, homogeneous or heterogeneous group of cancer cells.  It is a biochemical laboratory method for the characterization and identification of the DNA or RNA sequences of cancer cell(s).  Unlike whole genome, sequencing which is typically from blood cells, cancer genome sequencing involves direct sequencing of primary tumor tissue.  Similar to whole genome sequencing, the information generated from this technique include: identification of nucleotide bases (DNA or RNA), copy number and sequence variants, mutation status, and structural changes such as chromosomal translocations and fusion genes.

As with any genome sequencing project, the reads must be assembled to form a representation of the chromosomes being sequenced; with cancer genomes, this is done by aligning the reads to the human reference genome.  Since even non-cancerous cells accumulate somatic mutations, it is necessary to compare sequence of the tumor to a matched normal tissue in order to discover which mutations are unique to the cancer.

A major goal of cancer genome sequencing is to identify driver mutations: genetic changes which increase the mutation rate in the cell, leading to more rapid tumor evolution and metastasis.  A personal genomics analysis requires further functional characterization of the detected mutant genes, and the development of a basic model of the origin and progression of the tumor; this analysis can be used to make pharmacological treatment recommendations.

Understanding how genetic variation at the molecular level impacts disease is critical in the continued discovery and development of new and more effective therapies, and increasingly in the management of patient care through the use of more precise diagnostic tests.