Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues

Cancer is a significant concern in Malaysia, influenced by genetic defects from heredity and environment. Recent cancer research has focused on short tandem repeat (STR) markers for alteration studies in both solid and blood cancers. STRs, characterized by repetitive sequences with short repeat moti...

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Main Author: Omar, Izzah Syahira
Format: Thesis
Language:English
Published: 2025
Subjects:
Online Access:http://eprints.usm.my/62764/
http://eprints.usm.my/62764/1/IZZAH%20SYAHIRA%20BINTI%20OMAR-TESIS%20P-SKM002821%28R%29-E.pdf
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author Omar, Izzah Syahira
author_facet Omar, Izzah Syahira
author_sort Omar, Izzah Syahira
building USM Institutional Repository
collection Online Access
description Cancer is a significant concern in Malaysia, influenced by genetic defects from heredity and environment. Recent cancer research has focused on short tandem repeat (STR) markers for alteration studies in both solid and blood cancers. STRs, characterized by repetitive sequences with short repeat motif units, area valuable for forensic identification and paternity testing due to their high polymorphism. In diagnostic pathology, STR analysis could aid in tissue identification, addressing sample mislabelling and contamination. However, applying STR markers to cancerous tissues is challenging due to microsatellite instability (MSI) and loss of heterozygosity (LOH), which can affect STR genotyping. Despite their utility, there is a gap in understanding STR alterations across different molecular subtypes of breast cancer and leukemia. Therefore, this study aims to investigate the prevalence of STR alterations on breast cancer and leukemia sample tissues using QIAGEN Investigator 24plex QS kit. A total of 85 samples were genotyped, comprising 20 paired formalin-fixed paraffin-embedded (FFPE) breast cancer tissues and their corresponding normal adjacent tissues, 20 blood samples and five buccal swab samples from leukemia patients, and 20 blood samples from unrelated healthy individuals serving as controls. The findings revealed that among the four molecular subtypes of BC tissues, Luminal A subtype exhibited the highest LOH rate, while basal cell-like subtype displayed had highest MSI rate. No significant genetic alterations were found between the paired leukemia and their normal tissue samples but the D19S433 locus was significantly associated with leukemia compared to unrelated normal control. In summary, the genetic instability observed in human carcinomas has been recognized and may present difficulties for forensic genotyping and DNA profile comparison.
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spelling usm-627642025-09-17T04:14:49Z http://eprints.usm.my/62764/ Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues Omar, Izzah Syahira R Medicine RC254-282 Neoplasms. Tumors. Oncology (including Cancer) Cancer is a significant concern in Malaysia, influenced by genetic defects from heredity and environment. Recent cancer research has focused on short tandem repeat (STR) markers for alteration studies in both solid and blood cancers. STRs, characterized by repetitive sequences with short repeat motif units, area valuable for forensic identification and paternity testing due to their high polymorphism. In diagnostic pathology, STR analysis could aid in tissue identification, addressing sample mislabelling and contamination. However, applying STR markers to cancerous tissues is challenging due to microsatellite instability (MSI) and loss of heterozygosity (LOH), which can affect STR genotyping. Despite their utility, there is a gap in understanding STR alterations across different molecular subtypes of breast cancer and leukemia. Therefore, this study aims to investigate the prevalence of STR alterations on breast cancer and leukemia sample tissues using QIAGEN Investigator 24plex QS kit. A total of 85 samples were genotyped, comprising 20 paired formalin-fixed paraffin-embedded (FFPE) breast cancer tissues and their corresponding normal adjacent tissues, 20 blood samples and five buccal swab samples from leukemia patients, and 20 blood samples from unrelated healthy individuals serving as controls. The findings revealed that among the four molecular subtypes of BC tissues, Luminal A subtype exhibited the highest LOH rate, while basal cell-like subtype displayed had highest MSI rate. No significant genetic alterations were found between the paired leukemia and their normal tissue samples but the D19S433 locus was significantly associated with leukemia compared to unrelated normal control. In summary, the genetic instability observed in human carcinomas has been recognized and may present difficulties for forensic genotyping and DNA profile comparison. 2025-04 Thesis NonPeerReviewed application/pdf en http://eprints.usm.my/62764/1/IZZAH%20SYAHIRA%20BINTI%20OMAR-TESIS%20P-SKM002821%28R%29-E.pdf Omar, Izzah Syahira (2025) Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues. Masters thesis, Universiti Sains Malaysia.
spellingShingle R Medicine
RC254-282 Neoplasms. Tumors. Oncology (including Cancer)
Omar, Izzah Syahira
Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title_full Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title_fullStr Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title_full_unstemmed Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title_short Forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
title_sort forensic short tandem repeat markers alteration in leukemia cells and breast cancer tissues
topic R Medicine
RC254-282 Neoplasms. Tumors. Oncology (including Cancer)
url http://eprints.usm.my/62764/
http://eprints.usm.my/62764/1/IZZAH%20SYAHIRA%20BINTI%20OMAR-TESIS%20P-SKM002821%28R%29-E.pdf