title: Molecular and genetic epidemiology of cancer in low- and medium-income countries.
abstract: BACKGROUND
  Genetic and molecular factors can play an important role in an individual's cancer susceptibility and response to carcinogen exposure. Cancer susceptibility and response to carcinogen exposure can be either through inheritance of high penetrance but rare germline mutations that constitute heritable cancer syndromes, or it can be inherited as common genetic variations or polymorphisms that are associated with low to moderate risk for development of cancer. These polymorphisms can interact with environmental exposures and can influence an individual's cancer risk through multiple pathways, including affecting the rate of metabolism of carcinogens or the immune response to these toxins. Thus, these genetic polymorphisms can account for some of the geographical differences seen in cancer prevalence between different populations.
  
  
  OBJECTIVE
  This review explores the role of molecular epidemiology in the field of cancer prevention and control in low- and medium-income countries.
  
  
  RESULTS
  Using data from Human Genome Project and HapMap Project, genome-wide association studies have been able to identify multiple susceptibility loci for different cancers. The field of genetic and molecular epidemiology has been further revolutionized by the discovery of newer, faster, and more efficient DNA-sequencing technologies including next-generation sequencing.
  
  
  CONCLUSIONS
  The new DNA-sequencing technologies can play an important role in planning and implementation of cancer prevention and screening strategies. More research is needed in this area, especially in investigating new biomarkers and measuring gene-environment interactions.
authors.affiliation: Division of Hematology and Oncology, and Institute of Translational Epidemiology, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: jyoti.malhotra@mountsinai.org.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Malhotra
mesh_terms: D003906:Developing Countries; D059647:Gene-Environment Interaction; D020022:Genetic Predisposition to Disease; D006801:Humans; D017720:Molecular Epidemiology; D009369:Neoplasms / Q000453:epidemiology / Q000235:genetics*; D009386:Neoplastic Syndromes, Hereditary / Q000453:epidemiology / Q000235:genetics; D011110:Polymorphism, Genetic
keywords: cancer; genetics; low-income countries; molecular epidemiology