Probing disease-related genome variations for personalized medicine

As a result of advances in human genomics, a bold new era of personalized medicine is upon us. Identifying patterns of genetic variation will be crucial in helping physicians diagnose and treat diseases - even before symptoms appear.

IGS scientists are helping catalog the differences in DNA sequence among individuals to better understand the relationship among genes, physical traits, and disease, including cancer.

Many such studies here and elsewhere rely on robust analysis of genetic variation from small sequence differences (SNPs) in the genome. IGS are leaders within some large international consortia analyzing 100Ks of whole genomes, including the Trans-Omics for Precision Medicine (TOPMed) Project in collaboration with the Program in Personalized and Genomic Medicine. These studies are not also integrating multi-omics profiles of deeply phenotyped individuals to understand the systems biology of human personalized medicine.

At IGS, scientists have also developed new experimental approaches to identify and study alternative forms of genetic variation — such as insertions and deletions (INDELs) and transposon insertions — that are not as well studied. Such small additions and subtractions are common in the human genome and can impact a person's susceptibility to disease. IGS researchers are mapping such variations, examining insertion patterns in human populations, and identifying differences caused by transposable genetic elements.

The ultimate goal of such research is to "crack the code" and fully understand how a person's genetic variation affects health to enable physicians to predict a person's susceptibility to diseases and disease outcome.

As part of that quest, IGS scientists affiliated with the Greenebaum Cancer Center are helping find the genomic fingerprints of cancer, a term that encompasses more than 100 diseases — with disparate causes and risk factors — responsible for nearly 15% of all deaths. Cancer results from alterations (mutations) in the genome of cancerous cells. Research at IGS focuses on understanding both the breadth of mutations underlying specific cancers and how improving genomic data could reduce health disparities. As part of their research, IGS scientists are using cutting-edge sequencing and bioinformatics techniques to pinpoint mutations, chromosomal rearrangements, and gene expression profiles of cancerous cells. IGS is also incorporating population genetics approaches into the personalized analysis of non-European populations that have been traditionally understudied in cancer studies to address health disparities of these groups.

The goal is to identify the genes which are abnormally active or silenced compared to normal cells. That, in turn, will help scientists target the most important genes involved in various forms of cancer. Ultimately, determining the genetic makeup of a person's cancer will help physicians choose the most effective therapy for that individual.

University of Maryland School of Medicine