Final answer:
Using a transposon that contains the transposase gene within the IR regions may lead to increased transposition activity that could disrupt essential genes. Transposase aids in the transposition process, and its presence within IR regions can make the element hyperactive. However, transposition is often regulated by cellular mechanisms that limit its impact.
Step-by-step explanation:
Using a transposon that includes the transposase gene within the inverted repeats (IR) could potentially result in several issues. Transposase is an enzyme that facilitates the cut-and-paste mechanism of transposons, allowing them to be excised from one location in the genome and inserted into another. If the transposase gene is within the IR regions of a transposon, it may result in a high frequency of transposition, which could disrupt essential genes and interfere with normal cellular function.
Moreover, having the transposase gene within the IR regions might also make the transposon a composite element, like a Tn element, which can carry additional genes—for example, antibiotic resistance genes—thereby spreading these genes to other locations within the cell's DNA. The constant shuffling of genetic material due to a highly active transposase can have severe consequences if it interrupts vital genes or regulatory sequences.
However, it is also true that not all transpositions are problematic. Many occur in the non-coding regions of the genome, which account for a significant portion and do not necessarily disrupt gene function. Additionally, eukaryotic organisms, including humans, generally have two copies of each gene, so even if one copy becomes inactivated due to transposition, the other may suffice for survival. Furthermore, cells have developed mechanisms to regulate the activity of transposons, including silencing by small interfering RNAs (siRNAs) to mitigate the effects of rampant transposition.