The T-Cell Receptor β-Chain Locus Can Undergo Successive Gene Rearrangements

question 20

Essay

The T-cell receptor β-chain locus can undergo successive gene rearrangements to rescue unproductive V(D)J rearrangements.
A.What aspects of gene segment rearrangement at the TCRβ locus make this possible?
B.Can the immunoglobulin heavy-chain locus,which is also composed of V,D,and J segments,undergo successive rearrangements? If not,give the reasons for the difference.

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Definitions:

Antibodies

Proteins produced by the immune system to neutralize or destroy foreign substances such as bacteria and viruses.

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Describes individuals in the United States who have sub-Saharan African ancestry.

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Acquired Immunodeficiency Syndrome, a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV) which damages the immune system.