Final answer:
The high DNA similarity between different organisms, including humans and mice, indicates evolutionary relatedness and a shared common ancestor. Comparisons, such as with chimpanzees, show that we have even closer genetic ties to some species. Genomic studies reveal both the conservation of certain genes across species and the small but significant differences that can impact human health.
Step-by-step explanation:
The DNA of humans and mice being almost 92% similar indicates a significant evolutionary relatedness, suggesting that they may have shared a common ancestor at some point in their evolutionary history. Given that chimpanzees have a DNA similarity with humans of over 98%, it is reasonable to infer that chimpanzees shared the most recent common ancestor with humans compared to other organisms. The similarity in structures, such as the tailbone in humans relating to the tail in other mammals, is an example of homologous structures, which support the concept of a common ancestor.
Comparative genomics studies, which include the examination of DNA sequences and protein structures across different species, have shown us that despite the diversity of life, there is a common genetic thread that connects various organisms. The similarities in genetic material suggest the presence of homologous genes that have been preserved throughout evolution due to their essential roles in fundamental biological processes.
Genomic studies have also led to discoveries relating to human health, as the minute genetic differences between humans become significant in fields such as organ transplantation where HLA compatibility is crucial. This highlights the contrast between the overall genetic similarity among humans and the impactful nature of the small percentage of differences.