Familial context of genetic testing for cancer susceptibility: Sibling interactions and psychosocial responses.

摘要

Mutations in the genes BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer, and in recent years genetic testing has been used to identify such mutations. Researchers have theorized that in addition to an individual's test result, the family context may play an important role in psychosocial responses to genetic testing. The present study compared psychological and physiological responses among three types of adult sibling dyads with different combinations of genetic test results: carrier/carrier, carrier/noncarrier, noncarrier/noncarrier. Ninety-eight sibling participants (49 pairs) completed written questionnaires focused on their feelings and behavior toward each other. Seventy of these siblings (35 pairs) participated in structured, interactive sessions with each other.; Results from the study indicated that carrier/noncarrier pairs reported more state anger and less sibling affiliation during the session than carrier/carrier pairs reported. Compared with noncarrier/noncarrier dyads, carrier/noncarrier pairs reported higher levels of dominant support behavior, lower levels of affiliative support behavior, more state anger, more dominant behavior from their sibling during the session, and displayed fewer skin conductance responses. In a third type of contrast between carrier/carrier and noncarrier/noncarrier pairs, carrier/carrier dyads noted significantly more general sibling affiliation, more dominant support behavior, higher levels of dominance from their sibling, and displayed higher heart rates and skin conductance levels. The results of this study indicated that in general, pairs of siblings with opposite test results may respond with more negative perceptions of each other, while pairs in which both siblings are carriers may respond with more positive perceptions. More studies are needed to further delineate the impact of family context on psychosocial responses to genetic testing.