Blood Group, Vel System; Vel

Description

The Vel blood group system is defined by the presence of the Vel antigen on red blood cells. Vel is a high frequency antigen that shows variable strength, ranging from strong to weak. The rare Vel-negative blood type is inherited as an autosomal recessive trait and is typically unveiled when Vel-negative individuals develop anti-Vel antibodies after transfusion or pregnancy; Vel alloantibodies are never 'naturally occurring.' Individuals with anti-Vel antibodies may develop severe acute hemolytic transfusion reactions when transfused with Vel-positive blood. Individuals negative for the Vel antigen are rare and are required for the safe transfusion of patients with antibodies to Vel (summary by Daniels, 2002; Storry et al., 2013; Cvejic et al., 2013; Ballif et al., 2013).

Clinical Features

• Neoplasm
• Colon cancer