DNA sequencing and screening for point mutations in the human Lewis (FUT3) gene enables molecular genotyping of the human Lewis blood group system.
The human Lewis gene encodes an alpha(1,3/1,4)-fucosyltransferase responsible for synthesis of the Le(a) and a Le(b) antigens. 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 Trp68 to Arg and Thr105 to Met, and the other was homozygously mutated at nucleotides 59 (T --> G) and 1067 (T --> A), altering Leu20 to Arg and Ile356 to Lys. Using PCR we screened for these and additionally one other mutation at nucleotide 508 (G --> A) among 40 Caucasians. Of 15 Le(a-b-) individuals, 7 typed as le59/1067le202/314, 4 as le202/314le202/314 and 1 as le59/1067le59/1067. Of 21 Le(a-b+) and 4 Le(a+b-), 17 typed as LeLe and 7 as Lele202/314. A pedigree study of 8 Lewis-positive individuals showed that the mutations at nucleotides 202 and 314 were located on the same allele.
Elmgren
A
A
Department of Clinical Chemistry, Göteborg University Sahlgrenska Hospital, Sweden.
Börjeson
C
C
Svensson
L
L
Rydberg
L
L
Larson
G
G
D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D004912:Erythrocytes / Q000378:metabolism; D005838:Genotype; D006801:Humans; D007983:Lewis Blood Group Antigens / Q000235:genetics*; D008969:Molecular Sequence Data; D009710:Nucleotide Mapping; D010375:Pedigree; D017354:Point Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction; D044465:White People / Q000235:genetics
D007983:Lewis Blood Group Antigens