Author ORCID Identifier
0000-0002-6403-8548
Date of Graduation
5-2020
Document Type
Thesis (MS)
Program Affiliation
Genetic Counseling
Degree Name
Masters of Science (MS)
Advisor/Committee Chair
David Rodriguez-Buritica, M.D.
Committee Member
Syed S. Hashmi, M.D., MPH, Ph.D
Committee Member
Janice L. Smith, Ph.D
Committee Member
Victoria F. Wagner, M.S.
Committee Member
Kathryn Gunther, M.S.
Abstract
Copy number variants (CNVs) are a common finding in the clinical setting and contribute to both genetic variation as well as disease. Recently, studies have described the accumulation of multiple CNVs as a disease modifying mechanism. While it has been characterized how additional CNVs may play a role in phenotype, in which ways and to what extent sex chromosomes are involved has not been fully described. We performed a secondary data analysis using the DECIPHER database on 2,273 de-identified individuals with 2 CNVs. CNVs were designated primary and secondary based on our criteria and characteristics of both CNV groups were described. Further analysis was performed identifying differences in CNVs on the sex chromosomes vs autosomes. We found that CNVs on the sex chromosome have a significant difference compared to autosomes when comparing median size (p=0.013), pathogenicity classifications (p<0.001), and variant classification (p=0.001). We identified chromosome combinations for primary and secondary CNVs, and identified the X chromosome was the most common site for a secondary CNV. Additionally, we observed the plurality of secondary CNVs fell in the same chromosome as the primary CNV. From this study, we can conclude that the X chromosome is the most common site for secondary CNVs in a clinical setting. Identification of chromosome combinations for primary and secondary CNVs is essential in explanation of complex phenotypes and highlights areas of importance of the human genome.
Keywords
copy number variants, CNVs, sex chromosomes, additional CNVs