PT - JOURNAL ARTICLE AU - Dawna M. Gilchrist TI - Medical genetics: 3. An approach to the adult with a genetic disorder DP - 2002 Oct 29 TA - Canadian Medical Association Journal PG - 1021--1029 VI - 167 IP - 9 4099 - http://www.cmaj.ca/content/167/9/1021.short 4100 - http://www.cmaj.ca/content/167/9/1021.full SO - CMAJ2002 Oct 29; 167 AB - MANY GENETIC DISORDERS DO NOT MANIFEST themselves until the adult years. Such disorders often involve multiple genetic factors interacting with multiple environmental factors, over time, to produce a phenotype. This paper reviews the modes of inheritance of genetic disorders and describes the types of genetic testing that are currently available. It offers clues that should lead physicians to suspect that an adult patient might have a genetic disorder and raises issues that should be considered in counselling the patient about genetic testing. Resources for patients and their family physicians are also discussed.