Final answer:
Gene duplication during meiosis is typically a result of homologous recombination during the prophase I stage, where crossing-over and DNA breakage and rejoining can lead to duplicated gene sequences.
Step-by-step explanation:
The process generally thought to produce gene duplication during meiosis is called homologous recombination. During the prophase I stage of meiosis, when homologous chromosomes undergo synapsis, crossing-over may occur. This involves the breakage and rejoining of DNA between nonsister chromatids, which can lead to gene duplication. Errors that occur and are not corrected can produce duplications or translocations of DNA sequences. Duplications can elongate the chromosome and result in multiple copies of specific genes within an organism's genome, which can contribute to genetic variation and evolution. These extra gene copies can become the raw material for genetic diversification, potentially taking on new functions or regulatory patterns over time.