New Deletions in the Hermansky-Pudlak Syndrome Type 5 Gene in a Japanese Patient

Abstract

The Hermansky-Pudlak syndrome (HPS) is a rare disease characterized by oculocutaneous albinism and prolonged bleeding. HPS is caused by alterations in HPS1-10 and their related genes, comprising the biogenesis of lysosome-related organelles complex 1–3 and adapter protein 3. Here, we report a Japanese patient with HPS associated with mild hypopigmentation, nystagmus, and impaired visual acuity. Sequencing analyses of the mRNA of this patient revealed new deletions (ΔGA and ΔG) in the HPS5 gene. This was the first case of HPS5 gene deficiency in Japan, and the two above-mentioned deletions have not yet been reported among patients with HPS5.

Current landscape of Oculocutaneous Albinism in Japan

“…For this reason, patients with HPS present not only with albinism but also with systemic complications such as bleeding diathesis, pneumonia, colitis, and immune deficiency (Wei & Li, 2013). In Japan, 7 subtypes of HPS (HPS1, HPS2, HPS3, HPS4, HPS5, HPS6, and HPS9) have been identified so far (Araki et al., 2014; Kato et al., 2019; Miyamichi et al., 2016; Nishikawa et al., 2020; Okamura et al., 2018; Okamura, et al., 2019; Saito, et al., 2020; Saito et al., 2020) (Figure 2).…”