This strategy aims to provide a more comprehensive understanding of immune dysregulation in CVID, of potential hereditary patterns, and subclinical immunological traits within families.<h4>Methods</h4>Fifty-eight participants from nine families were included: Five families with a negative family history for CVID (FH-) and four families with a positive family history for CVID (FH+). This evidence concerns the gene FH and common variable immunodeficiency.