Final answer:
The incorrect statement when comparing the T-cell receptor α-chain locus with the immunoglobulin heavy-chain locus is that both loci are found on the same chromosome. The TCR α-chain is on chromosome 14 and the immunoglobulin heavy-chain is on chromosome 2.
Step-by-step explanation:
When comparing the T-cell receptor α-chain locus with the immunoglobulin heavy-chain locus, the statement that both loci are found on the same chromosome is incorrect. The correct statements about these loci are:
- Both loci undergo V(D)J recombination to generate diverse antigen receptor repertoires.
- Both loci have multiple gene segments, which contribute to the diversity of the antigen receptors.
- Both loci are involved in antigen recognition, as both T-cell receptors and immunoglobulins (or antibodies) are essential for the immune response.
However, the T-cell receptor α-chain locus and the immunoglobulin heavy-chain locus are located on different chromosomes. The TCR α-chain genes are located on chromosome 14 in humans, while the immunoglobulin heavy-chain genes are located on chromosome 2. Therefore, the incorrect statement is number 4, which claims both loci are found on the same chromosome.