DNA Sequencing and Screening for Point Mutations in the Human Lewis (FUT3) Gene Enables Molecular Genotyping of the Human Lewis Blood Group System

摘要

ABSTRACTThe human Lewis gene encodes an α(1,3/1,4)‐fucosyltransferase responsible for synthesis of the Leaand Lebantigens. To define the molecular background for non‐functional Lewis genes we have sequenced PCR‐amplified DNA fragments from two Le(a‐b‐) individuals. One was homozygously mutated at nucleotides 202 (T→C) and 314 (C→T), altering Trp68to Arg and Thrl05to Met, and the other was homozygously mutated at nucleotides 59 (T→G) and 1067 (T→A), altering Leu20to Arg and Ile356to Lys. Using PCR we screened for these and additionally one other mutation atnucleotide 508 (G→A) among 40 Caucasians. Of 15 Le(a‐b‐) individuals, 7 typed asle59/1067le202/314, 4 asle202/314le202/314and 1 asle59/10671e59/1067. Of 21 Le(a‐b+) and 4 Le(a+b‐), 17 typed asLeLeand 7 asLele202/314. A pedigree study of 8 Lewis‐positive individuals showed that the mutations at nucleotides 202 and 314 w