Investigating the genetic cause of oculocutaneous albinism type 2 in individuals of African descent through exome sequencing

Date
2024
Journal Title
Journal ISSN
Volume Title
Publisher
University of the Witwatersrand, Johannesburg
Abstract
Oculocutaneous Albinism type 2 (OCA2) is a hypopigmentation disorder caused by variants in the OCA2 gene. A 2.7kb intragenic deletion is known to be the common variant that causes OCA2 in individuals of African descent. This variant accounts for 78% of OCA2-causing variant in the Southern African population. The diagnostic utility for individuals who tested either negative or heterozygous for the common 2.7kb deletion remained unsolved. This study reports on the identification of the NM 000275.3:c.1503+5G>A variant found in 3/8 (37.5%) non-2.7kb deletion OCA2 chromosomes within a small sample of OCA2 patients from the Southern African population, strongly suggesting the possibility of a second common variant, pending a larger screening study. This variant has been previously described in this population, but new variant interpretation tools have now permitted its reclassification. Furthermore, limitations encountered during the interpretation of data step in this study highlight the importance of informative clinical and phenotypic data for improved and sensible interpretation of genetic results.
Description
A research report (in the format of a “submissible” paper) submitted in partial fulfillment of the requirements for the Degree of Master of Science in Medicine (Genomic Medicine) by Research and Coursework. to the Faculty of Health Sciences, School of Pathology, University of the Witwatersrand, Johannesburg 2024
Keywords
Oculocutaneous Albinism Type 2, OCA2, African, Exome sequencing, Common mutation, UCTD
Citation
Mmbi, Phophi Mmapole. (2024). Investigating the genetic cause of oculocutaneous albinism type 2 in individuals of African descent through exome sequencing [Master’s dissertation, University of the Witwatersrand, Johannesburg]. WireDSpace.