Pilot, prospective, mono-center study conducted in a population of healthy participants (free of cancer) for the analytical validation of circulating DNA analysis methods. The participants are employees of the institution. Their recruitement is carried out via internal posting (intranet and bulletin boards). The study participation will be strictly voluntary and without consequences on the professional situation of the participants.

Inclusion Criteria:

• 1 Adult volunteer (≥ 18 y.o.)
• 2 Participant free of cancer
• 3 Participant belonging to the personnel of Oncopole Claudius Regaud (IUCT-O) institution
• 4 Participant affiliated to a Social Health Insurance in France
• 5 Participant who received clear and understandable information about the research
• 6 Participant who signed an informed consent form before inclusion into the study and before any study specific procedure
• 7 Participant who accepts a blood draw in the context of the research
• 8 Participant who agrees to be contacted in the event of an incidental finding of a potential genetic abnormality

Exclusion Criteria:

• 1 Participant presenting with an associated pathology potentially preventing the adequate conduct of the study procedure
• 2 Participant presenting with a contra-indication to blood draw
• 3 Participant who reports to the investigator team
• 4 Participant who has forfeited his/her freedom bu administrative or legal award or who is under legal protection (curatorship and guardianship, protection of justice)