Genetic Variability in Slovenian Cohort of Patients with Oculocutaneous Albinism

• Main Authors: Tinka Hovnik, Maruša Debeljak, Manca Tekavčič Pompe, Sara Bertok, Tadej Battelino, Brabka Stirn Kranjc, Katarina Trebušak Podkrajšek
• Format: Article
• Language: English
• Published: Slovenian Chemical Society 2021-09-01
• Series: Acta Chimica Slovenica
• Subjects: oculocutaneous albinism; hermansky-pudlak syndrome type 1; next generation sequencing; genetic variant
• Online Access: https://journals.matheo.si/index.php/ACSi/article/view/6690
• ISSN: 1318-0207; 1580-3155

Oculocutaneous albinism (OCA) is an inherited disorder affecting the visual system and skin pigmentation. Our aim was to evaluate genetic and clinical heterogeneity in a cohort of Slovenian paediatric patients with clinically suspected OCA using advanced molecular-genetics approach. In as much as 20 out of 25 patients, genetic variants explaining their clinical phenotype were identified. The great majority of patients (15/25) had genetic variants in TYR gene associated with OCA type 1, followed by variants in TYRP1, SLC45A2 and HPS1 genes causative for OCA3, OCA4 and Hermansky-Pudlak syndrome type 1, respectively. We concluded that OCA phenotype could not predict genotype and vice versa. Nevertheless, the diagnostic yield after targeted next generation sequencing (NGS) was 80% and proved to be affective in our paediatric cohort of patients with various degree of OCA. Even in 16 patients with normal complexion the diagnostic yield was 62,5%. Interestingly, we have identified a patient of white European ancestry with OCA3, which is an extremely rare report, and one patient with OCA due to the Hermansky-Pudlak syndrome type 1.