Breast cancer are common on mediterranean basin. Epidemiological data suggest that breast cancer in young women (< 40years old) is more aggressive in the Maghreb countries comparatively to western countries. This aggressiveness could be associated with phenotypic and genotypic differences between this two populations.

The object of this study is to compare the genotypic and phenotypic differences between south and north shore of the mediterranean sea.

Inclusion Criteria:

• Patient have or have had a breast cancer diagnosed before 40 years old
• Breast cancer proven by histology
• BRCA1/2 analysis proposed, realized, ongoing
• Women >18 years old
• Patient with insurance
• Patient informed and no-opposed

Exclusion Criteria:

• Patient have or have had a breast cancer diagnosed after 40 years old
• Patient requiring tutorship or guardianship
• Adult patient protected by law

Patients have or have had a breast cancer diagnosed before 40 years old in two shores of the Mediterranean sea (France, lgeria, Marocco, Egypt, Tunisia)