title: An AQP1 allele associated with co(a-b-) phenotype.
abstract: The Colton (CO) blood group system consists of four antigens, Co(a), Co(b), Co3, and Co4, located on aquaporin-1 (AQP1), with Co(a) highly prevalent in all populations (99.8%). The Colton null phenotype, Co(a-b-), is very rare, and individuals with this phenotype lack the high-prevalence antigen Co3. To date, only six Co(a-b-) probands have been reported and four silencing alleles characterized. We identified an AQP1-null allele in a white woman with anti-Co3 caused by deletion of a G at nucleotide 601 (nt601delG) that results in a frameshift and premature termination (Val201Stop). Available family members were tested for the allele. Although anti-Co3 has been associated with mild to severe hemolytic disease of the fetus and newborn, the antibody was not clinically significant as evidenced by a low titer and delivery of asymptomatic newborns with moderate to weakly positive direct antiglobulin tests for all four pregnancies.
authors.affiliation: Immunohematology and Genomics Laboratory, New York Blood Center, Long Island City, NY 11101, USA.
authors.forename: S
authors.initials: S
authors.lastname: Vege
authors.forename: S
authors.initials: S
authors.lastname: Nance
authors.forename: D
authors.initials: D
authors.lastname: Kavitsky
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: T
authors.initials: T
authors.lastname: Horn
authors.forename: G
authors.initials: G
authors.lastname: Meny
authors.forename: C M
authors.initials: CM
authors.lastname: Westhoff
mesh_terms: D000328:Adult; D000937:Antigen-Antibody Reactions; D051398:Aquaporin 1 / Q000235:genetics*; D001483:Base Sequence; D001789:Blood Group Antigens / Q000235:genetics*; D003298:Coombs Test; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D010375:Pedigree; D010641:Phenotype; D011247:Pregnancy; D017422:Sequence Analysis, DNA
chemical_list: C496020:AQP1 protein, human; D001789:Blood Group Antigens; D051398:Aquaporin 1