Start Date: | 6/6/2017 | Start Time: | 12:00 PM |
End Date: | 6/6/2017 | End Time: | 2:00 PM |
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Event Description
BIOMED Master's Thesis Defense
Title:
Analysis of Subtelomeric Regions of Human DNA
Speaker: Eleanor Young, MS Candidate, School of Biomedical Engineering, Science and Health Systems
Advisor: Ming Xiao, PhD, Associate Professor, School of Biomedical Engineering, Science and Health Systems
Abstract: Subtelomeres are the distal 500kb regions on each chromosome which, due to high variation and diversity, are poorly defined and often misassembled to the reference. This region is followed by the telomere cap, which consists of repeating units of 5’TTAGGG3’. Further complicating understanding subtelomere regions is the fact that many different chromosomes share short pattern blocks called subtelomeric repeat elements (SRE). This can make determining whether a variant is truly a haplotype of one chromosome arm or just a misplaced contig from another chromosome challenging. The existing human genome reference for subtelomeric regions are often incomplete, containing padded empty portions to account for the subtelomeric structures and sometimes inaccurate, being a conglomeration of unique haplotypes.
Subtelomeric regions of DNA are important for several reasons. Due to high rates of recombination, subtelomeres give rise to many novel structures. Subtelomeres also help chromosomes recognize their homologous pair during meiosis and the absence of subtelomeres can prevent chromosome pairing. Subtelomeric regions do contain some genes. Subtelomeric regions are also vital for telomere regulation and integrity. Telomeres are dysfunctional in the presence of abnormalities in the subtelomeric region. As telomeres are an indicator of cell viability and stability this makes understanding the variation of subtelomeres extremely relevant. Subterminal deletions of chromosomes lead to serious mental handicaps and other problems but are hard to accurately recognize using G-bands, FISH and Sky methods, as the deviation from the expected results may just be due to diversity in the subtelomeric regions. A better understanding of the variation present would better enable identification of these disorders.
The short sequencing methods cannot resolve these regions due to the high rate of SREs. This is due mostly to the short read length which is unable to definitively be identified as a particular arm or haplotype since the entirety of the short molecule may be shared among several arms. We propose to use the combination of optical mapping and linked-sequencing technologies to completely assemble the human subtelomeric regions. |
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Location: Bossone Research Center, Room 709, located at 32nd and Market Streets. |
Audience: Undergraduate StudentsGraduate StudentsFacultyStaff |
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