Final answer:
The Diversity (D) segment is not found in the Human Ig Kappa Chain DNA, wherein only Variable (V) and Joining (J) segments are involved in the genetic rearrangement to produce the light chains of antibodies.
Step-by-step explanation:
The segment not found in the Human Ig Kappa Chain DNA is D (Diversity). The Kappa light chains of immunoglobulins consist of Variable (V) and Joining (J) segments, but not Diversity (D) segments.
In the maturation of germ-line B cells, DNA recombinase excises most of the V and J segments from the light chain gene and splices them together. This specificity is crucial for the formation of antibodies capable of recognising a vast array of antigens. The Kappa chain, specifically, undergoes recombination and splicing to create a large repertoire of VJ combinations resulting in unique antigen-binding sites. Unlike the heavy chain that uses V, D, and J segments to create diversity, the kappa light chain only rearranges V and J segments, as it lacks D segments.
Overall, these genetic rearrangements endow the adaptive immune system with its remarkable ability to target an extensive variety of pathogens through the production of unique immunoglobulin molecules.