An instance of hemophagocytic lymphohistiocytosis that is caused by an inherited genomic modification in an individual. The disease is hereditary hemophagocytic lymphohistiocytosis (MONDO_0015541, a Monarch Disease Ontology term). Also known as: familial hemophagocytic lymphohistiocytosis, genetic hemophagocytic lymphohistiocytosis, genetic hemophagocytic syndrome, primary hemophagocytic lymphohistiocytosis.