Collecting genetic information in primary care: evaluating a new family history tool

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.

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.

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.

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.

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.