Journal of Sciences, Islamic Republic of Iran

Identification of TYR Whole Gene Deletion in a Patient With Oculocutaneous Albinismby Next Generation Sequencing

Document Type : Original Paper

Authors

1 1 Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Islamic Republic of Iran. 5 Department of Research and Development, Harmonic Medical Genetics Lab, Isfahan, Islamic Republic of Iran

2 2 Department of Genetics and Molecular Biology, Najafabad Branch, Islamic Azad University, Najafabad, Islamic Republic of Iran. 5 Department of Research and Development, Harmonic Medical Genetics Lab, Isfahan, Islamic Republic of Iran

3 3 Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Islamic Republic of Iran. 5 Department of Research and Development, Harmonic Medical Genetics Lab, Isfahan, Islamic Republic of Iran

4 1 Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Islamic Republic of Iran. 4 Pediatric Inherited Diseases Research Center, Research Institute for Primordial Prevention of Noncommunicable Disease, Isfahan University of Medical Sciences, Isfahan, Islamic Republic of Iran. 5 Department of Research and Development, Harmonic Medical Genetics Lab, Isfahan, Islamic Republic of Iran

Abstract

Oculocutaneous albinism (OCA) comprises a group of genetically heterogeneous, autosomal recessive disorders characterized by a partial or complete absence of melanin pigmentation in the skin, hair, and eyes, associated with visual impairment. In this study, we analyzed several genes in an Iranian male infant affected by OCA. Clinical investigations and laboratory evaluations were performed for the proband. A pedigree chart was also drawn. Genomic DNA was extracted from the proband and both parents. A targeted gene panel was sequenced by next-generation sequencing to identify pathogenetic variants. A deletion of exons 1–5 in the TYR gene was confirmed in the proband. Logically, the parents should be heterozygous for this mutation. The results of this research demonstrate the efficiency of targeted high-throughput sequencing in diagnosing heterogeneous disorders like OCA and detecting large genomic rearrangements. This deletion mutation may have resulted from an unequal crossing-over event in an ancestral lineage.

Keywords

Main Subjects

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Journal of Sciences, Islamic Republic of Iran
Volume 35, Issue 4
October 2024
Pages 305-310