Codominance CScs×cc0 Gametes F,( all identical)9csc×dcc Ccscs Cccpc 1 c5C(spotted): 2 Cc(spotted/dotted): 1 c c(dotted
Codominant alleles Codominant alleles show both parental phenotypes ex ABo blood type: one gene with three alleles Different alleles different antigens IA= produces the A antigen produces the B antigen i(or o)=produces neither antigen Individuals produce antibodies to the antigen they do not have: IA/ JA= anti-B antibodies 卩/卩B=anti- A antibodies di= anti-B and anti-A antibodies
Codominant alleles • Codominant alleles show both parental phenotypes. • ex. ABO blood type: one gene with three alleles. Different alleles = different antigens • I A = produces the A antigen • I B = produces the B antigen • i (or Io ) = produces neither antigen. • Individuals produce antibodies to the antigen they do not have: • I A/ IA = anti-B antibodies • I B/ IB = anti-A antibodies • i/ i = anti-B and anti-A antibodies
ABo blood types Blood type AB Corresponding Red Phenotypes: blood Genotypes cell Type(s)of DEsugar B sugar A and B Molecule on cell sugars AIA B1B B B AB
e The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Phenotypes at Normal Carrier Diseased Dominance Different Levels of AA AS Ss Relations at Each Analysis Level of Analysis B-Globin polypeptide o A and are production 8 codominant Red blood cell shape at sea level Sickled cells u Normal Normal present A is dominant is recessive Red blood cell concentration at sea level Normal cells Normal Lower Red blood cell shape at high altitudes Sickled cells A and S show Normal present_______ Severe sickling incomplete dominance Red blood cell concentration at high altitudes 圈国: Normal Lower Very low, anemia Susceptibility is dominant to malaria A is recessive Normal susceptibility Resistant Resistant