Many conditions that result in decreased respiratory function have a genetic basis. In some conditions, DNA variants are the greatest contributor to disease development, and may directly cause disease, such as in Cystic Fibrosis or Alpha-1 Antitrypsin Deficiency. In other cases, genetic variations only play a small contributing role, which mildly increase the individual’s risk of developing a condition, such as in asthma development, and do not alone accurately predict whether an individual will actually develop the condition. In these conditions, the environment and other factors can also interact with genetic variants to contribute to lung diseases, but the biological mechanisms are not currently very well understood.

Medical testing for genetic variants is generally recommended for conditions with a significant genetic contribution. In this setting, genetic testing can be helpful to confirm a diagnosis in conjunction with other clinical diagnostic tests for these conditions. Gene testing may also be indicated to assess carrier status for individuals with a family history of a specific respiratory condition so as to assist with family planning.