Comparative analysis of the Y chromosome in humans and great apes

• Applicant: Professor Dr. Martin Kuhlwilm, Ph.D.
• Subject Area: Evolution, Anthropology ; Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 284798238

The Y chromosome has been used to gain insights into the evolutionary history of humans and other primates. Genes on this chromosome are relevant for sex-determination and regulation of development, but large repeat-rich, heterochromatic regions hampered studies targeting the whole chromosome. In the proposed project, I want to characterize the extent of genetic variation in Y chromosomes in great apes (Chimpanzees, Bonobos, Gorillas and Orangutans), and describe the evolutionary history of this particular chromosome by comparing the different great ape species.The first scope of the project will be the assembly of primate Y chromosomes. I will use de novo assembly tools to generate species-specific reference sequences from long sequencing reads. This will allow me to assess the architecture of the chromosome, and to determine structural variation between species, including humans. This will provide an important resource for evolutionary research on the great ape clade. The second part will be an assessment of genetic variation between individuals from the same species. This will be used to test the extent of natural selection and to estimate sex-specific population parameters. One interesting aspect of the interpretation will be correlations of genetic variation with mating patterns within species. Finally, I want to infer ancestral states and evolutionary rates in coding and putatively neutral regions. This will help elucidating social and environmental effects on the genetic variation in different great apes. The comparison between great ape and human variation, including archaic humans, will lead to a better understanding of the evolutionary context of modern human diversity.Recent technological advances make it possible to sequence Y chromosomes to a high quality. Currently, chromosome sorting and novel sequencing technologies (third generation sequencing) are being explored at the host institute, and will be used to generate high-quality sequencing datasets. I want to build de novo reference sequences from those, compare their architecture, and computationally analyze their variation.This project is relevant because the great ape species are dwindling, and their genetic diversity, which is highly informative for the origins of our own species, should be explored in wild-born individuals. Since Y chromosome diversity is almost absent in comparative evolutionary studies, this will contribute novel aspects to the understanding of human and great ape evolution.

• DFG Programme: Research Fellowships
• International Connection: Spain
• Host: Professor Dr. Tomas Marques-Bonet