SMIM1 variants rs1175550 and rs143702418 independently modulate Vel blood group antigen expression.

ABSTRACT: The Vel blood group antigen is expressed on the red blood cells of most individuals. Recently, we described that homozygosity for inactivating mutations in SMIM1 defines the rare Vel-negative phenotype. Still, Vel-positive individuals show great variability in Vel antigen expression, creating a risk for Vel blood typing errors and transfusion reactions. We fine-mapped the regulatory region located in SMIM1 intron 2 in Swedish blood donors, and observed a strong correlation between expression and rs1175550 as well as with a previously unreported tri-nucleotide insertion (rs143702418; C > CGCA). While the two variants are tightly linked in Caucasians, we separated their effects in African Americans, and found that rs1175550G and to a lesser extent rs143702418C independently increase SMIM1 an

SUBMITTER: Christophersen MK 

PROVIDER: S-EPMC5233989 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature