title: Mutations of the KLF1 gene detected in Japanese with the In(Lu) phenotype.
abstract: In(Lu) is characterized by a reduced expression of antigens in the Lutheran blood group system as well as other blood group antigens. Mutations of the erythroid transcription factor, KLF1, have been reported to cause the In(Lu) phenotype, and we investigated Japanese In(Lu) to estimate the prevalence of the phenotype and KLF1 polymorphism.
  
  
  
  Blood samples were screened by monoclonal anti-CD44 and the In(Lu) phenotype was confirmed by tube tests including adsorption and elution tests using anti-Luaand anti-Lub. KLF1, LU, and A4GALT genes were analyzed by polymerase chain reaction and sequencing.
  
  
  
  We identified 100 of 481,322 blood donors (0.02%), and the previously characterized 20 donors, who had the In(Lu) phenotype with the LUB/LUB genotype. A total of 100 of the 120 In(Lu) individuals had mutant KLF1 alleles, and we identified 13 known and 21 novel alleles. The mutant KLF1 alleles with c.947G>A (p.Cys316Tyr), c.862A>G (p.Lys288Glu), or c.968C>G (p.Ser323Trp) were major in the In(Lu) individuals. The P1 antigen of 29 In(Lu) (two P1/P1, 27 P1/P2) showed significantly weakened expression by hemagglutination.
  
  
  
  The prevalence of the In(Lu) phenotype in the Japanese population was 0.02%, and we identified 13 known and 21 novel KLF1 alleles. The KLF1 mutations cause the reduced expression of the P1 antigen.
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center, Saitama, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center, Saitama, Japan.
authors.forename: Kumi
authors.initials: K
authors.lastname: Obara
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center, Saitama, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Onodera
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center, Saitama, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Enomoto
authors.affiliation: Japanese Red Cross Central Blood Institute, Tokyo, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Ogasawara
authors.affiliation: Japanese Red Cross Central Blood Institute, Tokyo, Japan.|Japanese Red Cross Kanto-Koshinetsu Block Blood Center, Tokyo, Japan.
authors.forename: Hatsue
authors.initials: H
authors.lastname: Tsuneyama
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Blood Center, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Uchikawa
authors.affiliation: Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center, Saitama, Japan.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Inaba
mesh_terms: D019943:Amino Acid Substitution; D044466:Asian People; D015815:Cell Adhesion Molecules / Q000097:blood / Q000235:genetics*; D005260:Female; D005700:Galactosyltransferases / Q000096:biosynthesis / Q000235:genetics; D005915:Globosides / Q000096:biosynthesis / Q000378:metabolism; D006801:Humans; D007564:Japan; D051741:Kruppel-Like Transcription Factors / Q000097:blood / Q000235:genetics*; D008188:Lutheran Blood-Group System / Q000097:blood / Q000235:genetics*; D008297:Male; D020125:Mutation, Missense; D010641:Phenotype
chemical_list: C090228:BCAM protein, human; D015815:Cell Adhesion Molecules; D005915:Globosides; D051741:Kruppel-Like Transcription Factors; D008188:Lutheran Blood-Group System; C080774:erythroid Kruppel-like factor; C480041:galactopyranosyl-1-4-paragloboside; D005700:Galactosyltransferases; C045097:UDP-galactose-lactosylceramide alpha 1-4-galactosyltransferase