title: Functional characterisation of a complex mutation in the α(1,4)galactosyltransferase gene in Taiwanese individuals with p phenotype.
abstract: OBJECTIVE
  Individuals with p phenotype lack P1, P(k) and P antigens on red blood cells, presumably as a result of deficiency in the enzyme α(1,4)galactosyltransferase (A4GALT). The aim of this study was to explore the molecular background of a Taiwanese family with p phenotype.
  
  
  METHODS
  Blood samples from two p siblings and seven family members were investigated. The coding region of the A4GALT gene was analysed by polymerase chain reaction and direct sequencing. The wild- and mutant-complementary DNAs (cDNAs) of A4GALT were cloned into an expression vector and transfected to Chinese hamster ovary (CHO) cells. P(k) expression on the transfected cells was analysed by flow cytometry and the activities of A4GALT were measured by high-performance liquid chromatography.
  
  
  RESULTS
  The two individuals with p phenotype were homozygous for the complex mutation, which was caused by a combined deletion and insertion between nt 418 and 428. No expression of P(k) and no enzyme activity were observed in cells transfected with the mutant construct.
  
  
  CONCLUSIONS
  The first case of p phenotype in Taiwan was caused by a non-functional allele resulting from a homozygous complex mutation of A4GALT gene.
authors.affiliation: Kaohsiung Blood Center, Taiwan Blood Services Foundation, Kaohsiung, Taiwan.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Wang
authors.forename: C-F
authors.initials: CF
authors.lastname: Chang
authors.forename: H-C
authors.initials: HC
authors.lastname: Lin
authors.forename: K-S
authors.initials: KS
authors.lastname: Lin
authors.forename: K-T
authors.initials: KT
authors.lastname: Lin
authors.forename: C-M
authors.initials: CM
authors.lastname: Hung
authors.forename: T-M
authors.initials: TM
authors.lastname: Lin
mesh_terms: D000483:Alleles; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D005700:Galactosyltransferases / Q000172:deficiency / Q000235:genetics*; D006801:Humans; D008297:Male; D016254:Mutagenesis, Insertional; D010127:P Blood-Group System / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype; D017384:Sequence Deletion; D013624:Taiwan; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D010127:P Blood-Group System; D005700:Galactosyltransferases; C045097:UDP-galactose-lactosylceramide alpha 1-4-galactosyltransferase