A somewhat misused term that simply refers to the formation of a red blood cell antigen from the action of only a single allele. This is in direct contrast to the term “double dose,” which refers to the antigen formed when two identical alleles for that antigen are present (the person is genetically “homozygous”). This is further outlined (with pictures!) in the discussion on the dosage effect; please click that link for more details.
Back to Glossary List