VARIATION IN AMPLICONIC GENE COPY NUMBER AMONG HUMAN Y CHROMOSOMAL HAPLOGROUPS

Open Access
Author:
Ye, Danling
Area of Honors:
Veterinary and Biomedical Sciences
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Kateryna Makova, Thesis Supervisor
  • Robert Van Saun, Honors Advisor
Keywords:
  • human genetics
  • ampliconic genes
  • evolution
  • Y chromosome
Abstract:
Between the two sex chromosomes, the male-specific Y chromosome remains understudied compared to the X chromosome because it is highly repetitive in nature and difficult to sequence. Nevertheless, studies focusing on the Y chromosome are important as they provide insights on sexually dimorphic traits, as well as on the evolutionary relationships among individuals and their ancestry along the paternal lineage. Approximately 10.2 megabases (Mb) of the Y chromosome is contained in the ampliconic region, which consists of nine multi-copy gene families implicated in male-specific reproductive processes (Bhowmick et al. 2007; Bachtrog 2013). This study analyzes the ampliconic gene copy number variation of sixty-one males representing seventeen different Y chromosomal haplogroups from all over the world. Overall, the results show that copy numbers of ampliconic genes vary among different haplogroups and even among different individuals in the same haplogroup. Higher levels of variation were observed for the RBMY and TSPY gene families, while lower for the BPY2, CDY, DAZ, HSFY, PRY, XKRY, and VCY gene families. This research results pave the way for studying potential associations between ampliconic gene copy number and sexually dimorphic traits in humans in future studies.