Taking the family history in genetic disease: a guide for ophthalmologists

The family pedigree is an important tool in the field of ophthalmology. Recent advances in genetic testing for ophthalmic conditions underlie the need to offer genetic testing to patients when appropriate. Future availability of gene therapy for some ocular diseases further illustrates the importance of gene testing for patients seen in the ophthalmology clinic.

The pedigree is the first step in the genetic screening process and can guide the clinician in determining the likely genetic cause of a given disorder. Although not every patient warrants generating a pedigree, for patients whose condition may have a heritable basis, it is worthwhile to document the family history for several reasons. The pedigree gives us information about the mode of inheritance and can give clues toward a diagnosis. We can also determine whether family members are at risk for developing disease and calculate the recurrence risk for future offspring. The pedigree can help differentiate between a syndrome and an isolated ocular disease and may indicate the need for a specialist referral if there is risk of other systemic abnormalities. The pedigree gives us important information that may guide us in deciding which genes to test for and allows us to counsel the family appropriately.

The purpose of this review is to inform ophthalmologists on how to take a detailed family history relevant to possible genetic disorders, outline the information that can be obtained from the family history, and describe how this information can be used to optimize patient care.