Significant association of the tumor necrosis factor receptor 2 (TNFR2) gene with human narcolepsy

Acknowledgments: This work was supported by Grants‐in‐Aid from the Ministry of Education, Science, Sports and Culture of Japan and by the grant provided by the Uehara Memorial Foundation. Abstract: We report on the association study of the tumor necrosis factor receptor 2 (TNFR2) gene with human narcolepsy. A single‐nucleotide polymorphism in TNFR2, which is involved in an amino acid substitution [methionine(M)/arginine(R)] at position 196, was investigated in 149 Japanese narcoleptic patients and 204 healthy individuals as controls. Results reveal that the frequency of the TNFR2–196R allele significantly increased in the patients as compared with that in the controls (P=0.029), suggesting that TNFR2 is likely associated with the susceptibility to narcolepsy. In addition, the analyses of the relationship of TNFR2 and TNF‐α with the susceptibility to narcolepsy indicate the possibility that an additive effect on the susceptibility to the disorder lies between TNFR2–196R and TNF‐α(–857T) alleles.