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Human-Chimpanzee Divergent Genetics Essay

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Being human, we possess a quality that is unlikely to be found in other known organisms. Since perhaps the dawn of existence, the human psyche has strived to explain the origins of this quality and what it reveals about man’s conception. The ancient Greeks surmised that the Titan god Prometheus sculpted humans in the image of the gods from the mud of the earth. The ancient Egyptians posited that humans came into being from their sun god Ra’s tears. Now in modern times, scientists believe the key to our origins lies within our closest relative, Pan troglodytes, commonly known as the chimpanzee. But with nearly 99% of our DNA being completely identical to that of the chimpanzees, it is difficult to comprehend all the phenotypic differences …show more content…

The team, Polavarapu et al., hypothesized then that large sequences of insertions and deletions (INDELS) of between 80 to 12,000 base pairs long were significantly responsible for differences between humans and chimpanzees at the level of gene regulation, and these differences contributed to the phenotypic distinction between humans and chimps. In order to test the hypothesis, Polavarapu et al. identified and categorized the INDEL variation between the two species and mapped the variations in proximity to genes to establish whether or not the variations had any significant relationship to predetermined differences in the expression of the genes. The team discovered that 63% of the variations of INDELs between humans and chimpanzees were mostly due to retrotransposon insertions. Retrotransposons were defined and analyzed by the team as being genetic elements that can insert themselves into a genome, can increase a genome’s size, and are relatively stable. In addition, retrotransposon insertions were found to occur two times greater in the human genome than in the chimpanzee’s (Polavarapu et al., 2011).
Having identified that there were INDEL variations in protein-coding regions between humans and chimpanzees, Polavarapu et al. then reanalyzed a microarray data set that had been previously published by Khaitovich et al. (2005). The previous study had correlated sequence

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