Clinical characterization and risk profile of individuals seeking genetic counseling for hereditary breast cancer in Brazil.

Hereditary breast cancer (HBC) accounts for 5-10% of breast cancer cases and it significantly increases the lifetime risk of cancer. Our objective was to evaluate the sociodemographic variables, family history of cancer, breast cancer (BC) screening practices and the risk profile of cancer affected or asymptomatic at-risk women that undergo genetic counseling for hereditary breast cancer in public Brazilian cancer genetics services. Estimated lifetime risk of BC was calculated for asymptomatic women using the Gail and Claus models.

Molecular analysis of homocystinuria in Brazilian patients.

Background: Cystathionine beta-synthase (CBS) deficiency is the most common cause of homocystinuria. However, no data are available concerning the molecular basis of this disease in Brazilian populations.

Methods: We studied 14 Brazilian patients from 11 unrelated families using a combined screening approach, involving restriction analysis, single-strand conformational polymorphism (SSCP) scanning, and sequencing.