Alleles of the LAN blood group system: molecular and serologic investigations

Anti-Lan has been implicated in hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. The LAN blood group system is encoded by ABCB6, whose gene product, ABCB6, belongs to the ATP-binding cassette (ABC) efflux transporter superfamily. The purpose of this study was to characterize additional alleles by analyzing DNA from 14 (13 unrelated) subjects whose red blood cells were serologically defined as Lan-, Lan+(w) /-, or Lan+(w) .

Genomic DNA was extracted from blood samples recovered from liquid nitrogen storage. Intronic primers flanking each of the ABCB6 coding exons were used for polymerase chain reaction amplification. Amplicons were sequenced and analyzed by standard methods.

Among the study subjects, we identified five alleles (one with a nonsense change, three with frameshifts, one with a missense change) that encode the Lan- phenotype and four alleles (with missense changes) encoding either Lan+(w) or Lan+(w) /- phenotypes.

Of the nine alleles we identified, three were novel and six were previously documented in the dbSNP. Of these six, only one allele was previously associated with Lan negativity. To date, 19 ABCB6 alleles that encode Lan- or Lan+(w) /-, or Lan+(w) phenotypes have been described.