Breast cancer is the most commonly observed malignancy in women of the western world. The family history is the strongest risk factor for the disease. Two major genes, BRCA1 and BRCA2 that are involved in the familial breast and ovarian cancer have been described. Germ-line mutations of the BRCA1 gene have been linked to 85% of all hereditary breast and ovarian cancers. We performed a mutation screening ofthe entire codingregion of the BRCA1 gene in 29 Slovak families suspected of having inherited predisposition to breast cancer. For the analysis we used a combination of a single strand conformation polymorphism (SSCP), denaturing high-performance liquid chromatography (DHPLC) and sequencing. Genetic alterations were consistently indicated by SSCP and DHPLC and consequently confirmed by DNA sequencing as previously described pathogenic mutations. The patients with inherited BRCA1 mutations will undergo genetic counseling and cancer prevention health care program.