Introduction: Familial Mediterranean fever is the most frequent monogenic auto-inflammatory disorder that mostly affects Mediterranean population. Although this auto-inflammatory disease has historically been described as a recessive genetic disorder with homozygous or compound heterozygous mutations in the MEFV gene, an increasing number of cases are described with the detection of new single MEFV gene heterozygous mutations with modern molecular techniques. Case description: We report the cases of Caucasian French descent father and daughter who exhibited joint and abdominal inflammatory attacks resembling Familial Mediterranean Fever. Genetic studies revealed in both a heterozygous mutation p.T577N in exon 8 of MEFV gene, and in which colchicine was effective for preventing the attacks. Conclusion: Single heterozygous mutation of MEFV can be responsible for typical Familial Mediterranean Fever clinical pattern and, what is more, in non-Mediterranean ethnic background patients.