BRCA1/2-associated hereditary breast and ovarian cancer is the most common form of hereditary breast and ovarian cancer and occurs in all ethnicities and racial populations. Different BRCA1/BRCA2 pathogenic variants (PVs) have been reported with a wide variety among populations. In this study, we retrospectively analyzed prevalence and geographic distribution of pathogenic germline BRCA1/2 variants in families from Apulia in southern Italy and evaluated the genotype–phenotype correlations. Data were collected from Oncogenetic Services present in Apulian hospitals and a shared database was built containing Apulian native probands (n = 2026) that had undergone genetic testing from 2004 to 2019. PVs were detected in 499 of 2026 (24.6%) probands and 68.5% of them (342 of 499) were in the BRCA1 gene. We found 65 different PVs in BRCA1 and 46 in BRCA2. There were 10 most recurrent PVs and their geographical distribution appears to be significantly specific for each province. We have assumed that these PVs are related to the historical and geopolitical changes that occurred in Apulia over time and/or to a “founder effect”. Broader knowledge of BRCA1/2 prevalence and recurring PVs in specific geographic areas could help establish more flexible genetic testing strategies that may enhance our ability to detect high-risk subjects.

Background: Genetic testing has led to a considerable enhancement in the ability to identify individuals at risk of Hereditary Breast and Ovarian Cancer syndrome related to BRCA1/2 pathogenic variants, thus necessitating personalised prevention programs. However, barriers related to intrafamilial communication, privacy regulations, and genetic information dissemination hinder preventive care, particularly in Italy, where legal constraints limit the disclosure of genetic risks to at-risk relatives. This study examines the relationship between BRCA1/2 carriers’ communication challenges and three factors: cancer status, comprehension of genetic information, and the genetic counseling pathway accessed (Traditional Genetic Counseling, TGC vs. Mainstream Cancer Genetics, MCG). Methods: This multicenter, prospective, observational study included 277 BRCA1/2 carriers (probands and relatives) aged 18–80 from various Italian centers. Participants completed a sociodemographic form, a self-administered survey, and psychological assessments (Impact of Event Scale, IES and Distress Thermometer, DT). Categorical variables were compared using Pearson’s Chi-squared test or Fisher’s exact test based on sample size and expected frequencies, whereas continuous variables were analyzed using the Wilcoxon rank-sum test because of non-normal data distribution. Results: Among the 277 carriers (115 probands, 162 relatives), 79.4% received TGC and 20.6% MCG. The cancer prevalence was higher in probands (83%) than in relatives (22%). The probands exhibited greater psychological distress (higher IES and DT scores), and cancer-affected relatives had higher distress levels than healthy relatives (p = 0.008). While no severe psychological distress or PTSD was found, distress was more associated with cancer diagnosis than genetic status. Genetic comprehension was significantly higher in relatives (p = 0.007) and in those who underwent TGC compared to MCG (p < 0.001). TGC carriers also better understood genetic risks and management strategies (p < 0.001). Conclusions: Psychological distress and genetic comprehension significantly influenced the communication. TGC enhances understanding more effectively than MCG, highlighting the need for tailored support for both carriers and healthcare professionals to improve cascade counseling and testing rates, and cancer prevention. As we look into the future, we need to critically approach MCG, and determine how to address carriers understanding and prevention needs and reincorporate a more comprehensive genetic risk assessment into the MCG model.