Takashi Sasaki1, Norihiro Furusyo2, Aiko Shiohama3, Satoshi Takeuchi4, Takeshi Nakahara5, Hiroshi Uchi5, Tomomitsu Hirota6, Mayumi Tamari6, Nobuyoshi Shimizu7, Tamotsu Ebihara8, Masayuki Amagai8, Masutaka Furue5, Jun Hayashi2, Jun Kudoh9. 1. Center for Integrated Medical Research, Keio University School of Medicine, Tokyo, Japan; Department of Dermatology, Keio University School of Medicine, Tokyo, Japan. 2. Department of General Medicine, Kyushu University Hospital, Fukuoka, Japan. 3. Laboratory of Gene Medicine, Keio University School of Medicine, Tokyo, Japan. 4. Department of Dermatology, Kyushu University Hospital, Fukuoka, Japan. Electronic address: takeuchs@dermatol.med.kyushu-u.ac.jp. 5. Department of Dermatology, Kyushu University Hospital, Fukuoka, Japan. 6. Laboratory for Respiratory and Allergic Diseases, Core for Genomic Medicine, Center for Integrative Medical Sciences, The Institute of Physical and Chemical Research (RIKEN), Kanagawa, Japan. 7. Advanced Research Center for Genome Super Power, Keio University, Tsukuba, Ibaraki, Japan. 8. Department of Dermatology, Keio University School of Medicine, Tokyo, Japan. 9. Laboratory of Gene Medicine, Keio University School of Medicine, Tokyo, Japan; Advanced Research Center for Genome Super Power, Keio University, Tsukuba, Ibaraki, Japan. Electronic address: jkudoh@dmb.med.keio.ac.jp.
Abstract
BACKGROUND: Filaggrin (FLG) is a major protein component of the stratum corneum (SC) layer, and FLG loss-of-function mutations are a predisposing factor for atopic dermatitis (AD). Previous cohort studies of children from northern and western Europe have reported FLG loss-of-function mutation frequencies of 15.1-20.9% and 5.8-13.0% in AD and non-AD groups, respectively. OBJECTIVE: To elucidate the association between AD prevalence of FLG loss-of-function mutation carriers and climate conditions, we determined the AD prevalence and FLG loss-of-function mutation frequencies in a cohort of children from Ishigaki Island. Ishigaki Island has a subtropical climate with high humidity (monthly average, 60.8-78.7%) and high temperature (monthly average, 18.5-29.4°C) throughout the year. METHODS: We diagnosed AD prevalence and analyzed eight FLG loss-of-function mutations in the Japanese population against a cohort of 721 children from the Kyushu University Ishigaki Atopic Dermatitis Study (KIDS) cohort. Parents gave consent for the mutation analysis during their medical examinations from 2001 to 2006. RESULTS: Average AD prevalence was 7.3% per year, and a total of 127 children (17.6%) were diagnosed with AD at least once between 2001 and 2006. The average total serum IgE level differed significantly between the AD and non-AD groups (199.0 and 69.0IU/ml, respectively). Although five kinds of FLG loss-of-function mutations isolated in previous Japanese FLG mutation studies were identified, the FLG loss-of-function mutation frequency in children of the KIDS cohort was not significantly different between the AD and non-AD groups (7.9% and 6.1%, respectively; P=0.174). CONCLUSION: The FLG loss-of-function mutation frequency was not significantly different between the AD and non-AD groups in a cohort of children from Ishigaki Island, which has a subtropical climate, suggesting that FLG loss-of-function mutations are not always a predisposing factor for AD prevalence.
BACKGROUND:Filaggrin (FLG) is a major protein component of the stratum corneum (SC) layer, and FLG loss-of-function mutations are a predisposing factor for atopic dermatitis (AD). Previous cohort studies of children from northern and western Europe have reported FLG loss-of-function mutation frequencies of 15.1-20.9% and 5.8-13.0% in AD and non-AD groups, respectively. OBJECTIVE: To elucidate the association between AD prevalence of FLG loss-of-function mutation carriers and climate conditions, we determined the AD prevalence and FLG loss-of-function mutation frequencies in a cohort of children from Ishigaki Island. Ishigaki Island has a subtropical climate with high humidity (monthly average, 60.8-78.7%) and high temperature (monthly average, 18.5-29.4°C) throughout the year. METHODS: We diagnosed AD prevalence and analyzed eight FLG loss-of-function mutations in the Japanese population against a cohort of 721 children from the Kyushu University Ishigaki Atopic Dermatitis Study (KIDS) cohort. Parents gave consent for the mutation analysis during their medical examinations from 2001 to 2006. RESULTS: Average AD prevalence was 7.3% per year, and a total of 127 children (17.6%) were diagnosed with AD at least once between 2001 and 2006. The average total serum IgE level differed significantly between the AD and non-AD groups (199.0 and 69.0IU/ml, respectively). Although five kinds of FLG loss-of-function mutations isolated in previous Japanese FLG mutation studies were identified, the FLG loss-of-function mutation frequency in children of the KIDS cohort was not significantly different between the AD and non-AD groups (7.9% and 6.1%, respectively; P=0.174). CONCLUSION: The FLG loss-of-function mutation frequency was not significantly different between the AD and non-AD groups in a cohort of children from Ishigaki Island, which has a subtropical climate, suggesting that FLG loss-of-function mutations are not always a predisposing factor for AD prevalence.
Authors: Laura Cau; Valérie Pendaries; Emeline Lhuillier; Paul R Thompson; Guy Serre; Hidenari Takahara; Marie-Claire Méchin; Michel Simon Journal: J Dermatol Sci Date: 2017-02-20 Impact factor: 4.563