Family history red flags

GECKO point of care june 26th

Red flags indicate to healthcare providers that their patient (or their patient’s family) may be at increased risk for a genetic condition.  The best way to identify red flags is by taking a family history (in addition to a personal health history).

Download the quick reference Red flags point of care tool.

Find a family history taking tool here.


Red Flags

Multiple affected family members may

  • Indicate they have the same or a related disorder
    • e.g. family history of endometrial and colon cancer (Lynch syndrome)
  • Illustrate both shared genetics and environmental risk factors
  • Demonstrate pattern of inheritance (recessive, dominant, X-linked)

Earlier age of onset of disease (or symptom) than typically expected

  • May demonstrate genetic predisposition in an individual who is more susceptible to environmental risk factors
    • e.g. pre-menopausal breast cancer (BRCA1 or BRCA2 mutation);  premature ovarian failure before age 40 (fragile X syndrome carrier) 

Disease occurring in an individual of the less commonly affected sex

  • e.g. breast cancer in a male

Presence of disease in the absence of other precipitating factors

  • e.g. sudden unexplained death in an athletic 20-year-old (hypertrophic cardiomyopathy); diabetes mellitus (hereditary hemochromatosis or myotonic dystrophy)


  • Some genetic disorders are more common in certain ethnic groups
    • e.g. Tay-Sachs disease, Gaucher disease, Familial dysautonomia, Canavan disease  in Ashkenazi Jewish individuals;  Hemoglobinopathies (thalassemia, sickle cell anemia) in individuals of Mediterranean, African, Middle Eastern and South East Asian ancestry


  • Generally defined as a union between two individuals related as second cousins or closer
  • The incidence of congenital anomalies in the offspring of first cousins has been estimated to be 1.7–2.8% higher than the background population risk (which is 2-3%), mostly attributable to autosomal recessive diseases.

History of congenital anomalies (e.g. heart defect, imperforate anus), still birth, childhood death, infertility, more than three unexplained miscarriages

  • May be suggestive of underlying genetic etiology such as a single gene disorder or a familial chromosome re-arrangement


GenetiKit project resources

NCHPEG (National Coalition for Health Professional Education in Genetics) for products and programs

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