Which genes encode MHC class I and class II proteins?

Which genes encode MHC class I and class II proteins?

• A. MHC-I: HLA-A, -B, -C; MHC-II: HLA-DR, -DP, -DQ
• B. MHC-I: HLA-X, -Y; MHC-II: HLA-Z
• C. MHC-I: HLA-A, -B; MHC-II: HLA-DR
• D. MHC-I: HLA-DR, -DP, -DQ; MHC-II: HLA-A, -B, -C

Answer: (A)

MHC proteins are encoded by distinct gene sets for each class. For humans, the class I heavy chains are produced by HLA-A, HLA-B, and HLA-C, while the class II chains come from HLA-DR, HLA-DP, and HLA-DQ loci. So the genes encoding MHC class I proteins are HLA-A, HLA-B, HLA-C, and the genes encoding MHC class II proteins are HLA-DR, HLA-DP, HLA-DQ. The other options mix incorrect loci or assign the wrong class to the loci, which is why the listed sets align with the correct pairing.

MHC proteins are encoded by distinct gene sets for each class. For humans, the class I heavy chains are produced by HLA-A, HLA-B, and HLA-C, while the class II chains come from HLA-DR, HLA-DP, and HLA-DQ loci. So the genes encoding MHC class I proteins are HLA-A, HLA-B, HLA-C, and the genes encoding MHC class II proteins are HLA-DR, HLA-DP, HLA-DQ. The other options mix incorrect loci or assign the wrong class to the loci, which is why the listed sets align with the correct pairing.