A group of scientists from Penn State, used various Y-specific male chromosomes of great apes to determine how the chromosome developed along with studying the implications it has had on male fertility within humans. Based on the difficulties shared by sequencing a Y chromosome, for instance repetitive sequences, assembling sequences, and aligning sequences for comparison, the team had to create their own computational protocols to address the biological questions at hand. With regards to previous research, teams had already sequenced the DNA of chimpanzees, humans, and gorillas, to determine that the Y chromosome human's possess is more closely related to gorillas than chimp, and this lead to the use of the Bonobo and orangutan DNA for comparison. From the sequencing of the bonobo, it had determined that there were accelerated rates of DNA sequence change and gene loss, which now has the possibility of the pattern change prior to the evolutionary split of the two species. Orangutans acted "as expected" and served as a control group to to the other great apes. The scientists then tried to create a Y-chromosome based on the ancestors of the great apes, to determine the point at which they had separated as a species to help determine the evolutionary chain. Very interesting in terms of genetic evolution, and provides a large amount of insight into the difficulties of determining when and where gene loss occurs within the period of which species split. Hopefully the research the group has done provides a clearer image for the future in more research with regards to the Y-chromosome, and it can help determine the DNA in other species.