Background: The family history is a time-honoured method for identifying genetic predisposition. In specialist practice the standard approach is to draw up a family tree based on a genetic pedigree interview, but this is too time-consuming and focused on single gene disorders to be applicable in primary care.
Objectives: To assess the ability of a brief self-administered Family History Questionnaire (FHQ), given to patients when they register with a GP, to identify genetic risk.
Methods: A comparative study. Informants completed an FHQ at registration, and later participated in a genetic pedigree interview. Two clinical geneticists independently scored results obtained with each instrument. Discrepancies were agreed by consensus. The genetic risks identified by the two instruments were compared.
Results: 326 new registrants completed the FHQ, and 121 also completed the genetic interview. 24% of FHQs and 36% of genetic interviews resulted in a score 'higher than population risk'. There was 77% agreement in the scores obtained with the two instruments, with a moderate kappa of 0.52. (95% CI 0.40-0.64). There was 90% agreement in the scores for a family history of premature coronary heart disease (Kappa 0.67; 95% CI 0.49 to 0.85). The instruments were equally effective in identifying ethnicity-related risk of common recessive disorders.
Conclusions: The FHQ identified most informants with genetic risks that are appropriately addressed in primary care-those with a family history of premature coronary heart disease, those warranting specialist referral, and those who might appropriately be offered carrier testing. However, it was less effective in identifying those with a possible Mendelian disorder for whom more information was required.