We have recently established the landscape of germline mitochondrial DNA (mtDNA) variants and somatic mtDNA mutations in pediatric malignancies, from mining the paired tumor-normal whole-genome sequencing data of over 600 pediatric cancer patients of 23 subtypes. A main finding of the study is that the mtDNA mutation profile, as well as the composition, varies significantly from one tumor subtype to another. This finding argues strongly for the contributory roles of both germline mtDNA variants and somatic mtDNA mutations to tumorigenesis and tumor heterogeneity of pediatric cancers, which differ from one tumor subtype to another.
We are mining the WGS data sets for germline mtDNA variants and tumor-only mtDNA mutations, determine the mitochondrial haplogroup of each patient, establish the genetic profile of somatic mtDNA mutations in each patient and overall, and compare all of the above with that of other tumor subtypes from our earlier study.
What are the goals of this project?
The goal of this study is to interrogate the whole-genome sequencing data of the pediatric brain tumor patients for germline mitochondrial DNA (mtDNA) variants and somatic mtDNA mutations, in order to understand their contributory roles, if any, to both the genetic risk for and the cancer development of pediatric brain tumors.
The Children's Brain Tumor Network contributed to this project by providing access to the Pediatric Brain Tumor Atlas.
PI: Xiaowu Gai, PhD - Children's Hospital Los Angeles