Chapter 20 – Genetic Factors Involved in Susceptibility to Lung Disease

Many diseases are complex disorders that involve multiple extrinsic (external) and intrinsic (internal) components. An important role for environmental factors in disease is supported by numerous epidemiological studies that demonstrate strong associations between exposure and disease morbidity and mortality, including pulmonary diseases such as asthma, chronic obstructive pulmonary disease (COPD), and lung cancer. While extrinsic factors are important for disease development and progression, not everyone responds to the environment in the same way, indicating intrinsic components are important as well. Studies have found evidence of linkage between genetic markers and unobserved susceptibility loci for many lung diseases and their associated phenotypes, although such evidence is seldom definitive within any one study and often is conflicting across studies. Additional considerations for disease susceptibility are the multiple possible interactions between environmental factors and genetic make-up that together affect disease state. In this chapter, we review the genetic factors that may contribute to environmental and occupational lung diseases, and approaches used to identify these factors. Identification of important susceptibility genes and their interaction with the environment should provide novel insight to prevention and treatment of lung disease.