The exact prevalence of BRCA1 founder mutations in Latvia is difficult to investigate due to relatively high heterogeneity of the Latvian population; however, in the analysis of a population screening of hereditary cancer syndromes in the Valka district of Latvia, the prevalence of BRCA1 founder mutations in the Latvian population was estimated at approximately 0.05% [7]. Here, BRCA1 is linked to Inherited cancer-predisposing syndrome.