Familial haemophagocytic lymphohistiocytosis in patients who are heterozygous for the A91V perforin variation is often associated with other genetic defects

Summary The heterozygous A91V mutation in PRF1 is identified more frequently in patients with familial haemophagocytic lymphohistiocytosis (FHLH) than in healthy individuals in North America. Additional mutation(s) in either Munc13‐4 or PRF1 were found in 10 of 24 patients with FHLH who are heterozygous for A91V. A91V‐ PRF1 by itself is not disease causing.