Chapter 13: Genetics in Medical-Surgical Nursing

Cell division processes are examined through mitosis and meiosis, highlighting their roles in maintaining genetic integrity and producing reproductive cells. The chapter thoroughly explores genetic mutations, distinguishing between inherited germline mutations and acquired somatic mutations caused by environmental factors, and categorizes genetic disorders into single-gene conditions like cystic fibrosis and sickle cell disease, multifactorial diseases such as diabetes and cardiovascular disease, and chromosomal abnormalities including Down syndrome. Inheritance patterns receive detailed attention, covering autosomal dominant conditions like Huntington disease and Marfan syndrome, autosomal recessive disorders requiring two mutated alleles, X-linked recessive conditions predominantly affecting males, and rare Y-linked inheritance. The Human Genome Project's contributions to modern medicine are discussed alongside epigenetic mechanisms that modify gene expression without altering DNA sequences. Comprehensive coverage of genetic testing modalities includes carrier screening, newborn screening programs, prenatal and preimplantation genetic testing, diagnostic and predictive testing for conditions like BRCA-associated cancers, and forensic applications. Pharmacogenomics receives emphasis as a personalized medicine approach using genetic variation to optimize drug therapy, exemplified by cytochrome P450 enzyme testing for warfarin dosing and HER-2 testing for targeted cancer treatment. Emerging therapeutic approaches including gene therapy using viral vectors and stem cell therapy utilizing various cell potency levels are explored. The chapter addresses critical ethical, legal, and social implications of genetic testing, including privacy concerns, insurance discrimination protections under the Genetic Information Nondiscrimination Act, and family decision-making processes. Nursing responsibilities are emphasized throughout, including family history collection, pedigree construction, patient education regarding genetic risks and screening options, collaboration with genetic counselors, and providing comprehensive support during genetic testing decisions and their emotional consequences.