Final answer:
A chromosome duplication with the duplicated region next to the original is called a tandem duplication, and this can have various effects on an organism depending on the genes involved.
Step-by-step explanation:
A chromosome duplication in which the duplicated region is immediately adjacent to the original segment is called a tandem duplication. In this type of duplication, the sequence of genes is repeated in the same order on the same chromosome, which can have various effects on an organism's phenotype and can be involved in certain diseases or disorders.
The term is distinct from other chromosomal mutations such as translocation, where a chromosome segment dissociates and reattaches to a different, nonhomologous chromosome, which can be associated with certain cancers and schizophrenia, but without duplicating genetic material.