Despite how it helps determine the gender of every mammal on Earth, the Y chromosome is puny in comparison to its X counterpart, and makes up only about one or two percent of all genetic material found in the cells of males. Its size has traditionally made analyzing the content on the Y chromosome extremely difficult. However, Penn State researchers recently developed an easier method to sequence the Y chromosome’s genetic information that may help simplify its study in both humans and animals.

The technique, known as flow-sorting, works by increasing the amount of data information on the Y chromosome by 30 percent. After increase, the data is further enhanced using a computation technique called RecoverY. In a recent statement, study co-author Paul Medvedev explained that this works to help “sort the data into Y and non-Y sequences based on how frequently similar sequences appeared” in the data.

By combining flow-sorting with other common gene-sequencing techniques, the team was able to successfully sequence the Y chromosome of a male gorilla. For centuries, the gorilla was believed to be little more than a mythical man-beast who lived in the African bush and kidnapped human women. Today, we know the gorilla to be a gentle, intelligent species of Great Ape. The Penn State team learned we may be even more like this gentle giant than previously known. While chimpanzees are modern-day humans’ closest living genetic relatives, researchers found that human Y chromosomes were actually more related to the male gorillas’ Y chromosomes.

"In regions of the chromosome where we can align all three species, the sequence similarity fits with what we know about the evolutionary relationships among the species — humans are more closely related to chimpanzees,” Kateryna Makova, a study co-author, said in a statement.

What Does This Mean?

The study’s findings have diverse and far-reaching implications. For example, more knowledge of the human Y chromosome could help researchers better understand human male infertility and male-specific mutations. According to the Turek Clinic, a fertility clinic in Beverly Hills, Ca., although about 40 percent of couple infertility is caused by male factors, researchers still know little about the genetics of male infertility.

“There are several genes on the Y chromosome that are involved in male fertility,” Makova told Medical Daily in an email. “By studying their evolution we hope to shed light on male infertility disorders.”

Sequencing of the gorilla Y chromosome may also be useful to help conserve gorillas, an endangered species. Conservation genetics is a science that aims to apply genetics to conserving and restoring species biodiversity. The ability to sequence the Y chromosome could help geneticists link gorilla fathers to gorilla infants, and allow for better tracking of population migration within endangered species.

Source: Tomaszkiewicz M, ,Rangavittal S, Cechova M, et al. A Time- and Cost-Effective Strategy to Sequence Mammalian Y Chromosomes: An Application to the de novo Assembly of Gorilla Y. Genome Research. 2016