This study has been set up in order to characterize phenotypes and genotypes of patients with early onset enteropathies.

In that goal, Investigators will collect biological samples (mainly blood) of patients suffering from early onset enteropathies and their healthy relatives.

This study specifically aims at the genetic analysis of early onset enteropathies with the goal in mind to delineate human pathways necessary to maintain intestinal homeostasis despite the considerable density of microbes colonizing the distal part of the human intestine.

Main Inclusion Criteria:

• Severe chronic enteropathy
• Patients developing their first symptoms within the first 6 years of life and, in priority within the first two years of life, or patients with a disease of later onset, in case of a familial history suggestive of inherited mutations notably in families comprising several affected members
• OR : Be a patient's relative, even if presenting with enteropathy of later onset.

Main Exclusion Criteria:

• Subject having participated to any therapeutical clinical study in the 30 days preceding the inclusion in this study,

Inclusion of patients with chronic severe entheropathy and of their healthy relatives