Standardized Human Pedigree Nomenclature: Update and Assessment of the Recommendations of the National Society of Genetic Counselors

In 1995, the Pedigree Standardization Task Force (PSTF) of the National Society of Genetic Counselors (NSGC) proposed a system of pedigree nomenclature. Recently, the PSTF (now called the Pedigree Standardization Work Group or PSWG) sought evidence that the published symbols met the needs of health professionals, were incorporated into health professional training and were utilized in publications. We searched PubMed and reference lists of select publications, reviewed the Instructions for Authors of several journals, searched the websites of professional societies, sought comment from the membership of the NSGC, and looked at recommendations and training practices of various health professional organizations. Many journals still do not cite specific standards for pedigrees, but those found cited the PSTF nomenclature. We did not find significant objections or alternatives to the 1995 nomenclature. Based on our review, we propose only a few minor stylistic changes to the pedigree symbols. The pedigree nomenclature of the NSGC is the only consistently acknowledged standard for drawing a family health history. We recommend regular and continued review of these pedigree standards to determine if additional symbols are needed to accommodate changes in clinical practice to ensure that the symbols continue to meet the needs of health professionals and researchers as well as adhere to evolving ethical and privacy standards. All health professionals, trainees, and researchers should be made aware of the utility of using a common pedigree nomenclature in clinical practice and publication. This will become particularly important as electronic medical records become more widely utilized.