Homozygous Expression of a Missense Mutation at Nucleotide 385 in the FUT2 Gene Associates with the Le(a+b+) Partial-Secretor Phenotype in an Indonesian Family

Abstract A new point mutation was found in the coding sequence of the secretor FUT2 gene. This missense mutation with an A→T substitution at nucleotide 385 resulted in an amino acid change of Ilel29 to Phe129. This mutation showed a clear genetic trait in an Indonesian pedigree and, when appearing in a homozygous form, it was associated with the red cell Le(a+b+) and salivary partial-secretor phenotype. This result suggests that the molecular basis for the Le(a+b+) and associated partial-secretor phenotype is caused by a partially inactivating amino acid change in the α(1,2)fucosyltransferase coded for by this new FUT2 allele.