Lea and Calzone have provided an outstanding overview of genetics and genomic research applicable to the subspecialty of oncology nursing. The ever-emerging discoveries in this discipline mandate that nurses understand the key concepts of genetics and genomics and their everyday application to comprehensive care of the oncology patient and family throughout all phases of the trajectory of cancer care.
All nurses need to be familiar with the document Essentials of Genetic and Genomic Nursing. This resource emphasizes that all nurses should understand the role of both genetics and genomics in healthcare. Genetics is the study of individual genes and the ways in which their expression or dysfunction impacts the development of relatively rare single-gene disorders. Many mistakenly believe that genetics and genomics are interchangeable and that genetics explains how all disease, including cancer, develops.
Genomics is an exploding area of interest in oncology care and includes the study of all genes in the human genome together, including their interactions with each other and the environment, as well as the influence of psychosocial and cultural factors on the development of disease, such as cancer. Lea and Calzone provide numerous relevant clinical examples of applied genomics, describing how the science of genomics relates to personalized healthcare.
Nurses need to be able to explain basic concepts of genetics and genomics to patients and families. One area that often requires clarification involves the transmission of hereditary risk. Gene mutations can be inherited, spontaneous, or acquired. Inherited gene mutations, called germline mutations, are present in all body cells. They are passed on from parent to child in reproductive cells (the egg and sperm), and are present in all of the cells in that child's body when the body cells reproduce. A spontaneous mutation can occur in individual eggs or sperm at conception. A person who has the new, spontaneous mutation is at risk of passing the mutated gene to his or her children.
Acquired mutations, also called somatic mutations, occur in body cells other than egg or sperm. They involve changes in DNA that take place after conception, during a person's lifetime. Acquired mutations result from cumulative changes in body cells other than egg or sperm, called somatic cells. Somatic gene mutations are passed on when the cells they contain reproduce. Frequently patients will state that they underwent genetic testing, thinking that such testing implies hereditary risk, when in reality they may have had testing of their tumor, such as HER2 (human epidermal growth factor receptor 2) testing to direct treatment decisions. Nurses need to be able to explain basic genetic concepts in terms that can be understood by patients and families.
It is important for oncology nurses to recognize when a person may potentially have a hereditary (germline mutation) risk for developing cancer and when it is appropriate to refer that individual and family for further genetic risk assessment, evaluation, and possibly genetic testing. This relatively small subset of individuals and families should be referred to a credentialed genetics professional for evaluation. Clearly, identification of a germline mutation and family members at significantly high risk for developing cancer can result in targeted and potentially effective prevention and early detection strategies, and this traditional application of genetics is essential to good oncology nursing.