Genotypes and phenotypes in 20 Chinese patients with type 2 Gaucher disease

Current opinion on pluripotent stem cell technology in Gaucher's disease: challenges and future prospects

Gaucher's disease (GD) is a rare autosomal recessive genetic disorder caused by mutations in the GBA1 gene. Mutations in the gene lead to the deficiency of glucocerebrosidase, an enzyme that helps in the breakdown of glucosylceramide (GlcCer) into ceramide and glucose. The lack of the enzyme causes GlcCer accumulation in macrophages, resulting in various phenotypic characteristics of GD. The currently available therapies, including enzyme replacement therapy and substrate reduction therapy, only provide symptomatic relief. However, they grapple with limitations in efficacy, accessibility, and potential side effects. These observations laid the foundation to search for new approaches in the management of GD. Induced pluripotent stem cells (iPSCs) technology emerges as a beacon of hope, offering novel avenues for future GD therapies. The true magic of iPSCs lies in their ability to differentiate into various cell types. By reprogramming patient-derived cells into iPSCs, researchers can generate personalized models that recapitulate the genetic and phenotypic characteristics of the GD. These models are valuable tools for dissecting intricate disease pathways, developing novel therapeutic targets, and enhancing the drug development process for GD. This review emphasizes the significance of iPSCs technology in GD management. Further, it addresses several challenges that are being encountered in the application of iPSC technology in the management of GD. In addition, it provides several insights into the future aspects of iPSC technology in the management of GD.

c.754T>A homozygous mutation described for the first time in three Moroccan patients with Gaucher disease

Gaucher disease (GD) is a lysosomal storage disorder caused by glucocerebrosidase (GBA) deficiency. There are three subcategories of GD: Type 1 is characterized by the absence of primary central nervous system involvement; type 2 is an acute neuropathic disorder; and type 3 is chronic neuropathic. The correlation between genotype and phenotype is sometimes difficult to establish. The F213I (c.754T>A p.Phe252Ile) mutation was reported to be a unique mutation in Asia. To our knowledge, this is the first time the c.754T>A p.(Phe252Ile) mutation (homozygous state) is reported in a Moroccan population and is associated with GD type 2 (two patients) and GD type 3 (one patient).

Diagnosing neuronopathic Gaucher disease: New considerations and challenges in assigning Gaucher phenotypes

Gaucher disease (GD), resulting from biallelic mutations in the gene GBA1, is a monogenic recessively inherited Mendelian disorder with a wide range of phenotypic presentations. The more severe forms of the disease, acute neuronopathic GD (GD2) and chronic neuronopathic GD (GD3), also have a continuum of disease severity with an overlap in manifestations and limited genotype-phenotype correlation. In very young patients, assigning a definitive diagnosis can sometimes be challenging. Several recent studies highlight specific features of neuronopathic GD that may provide diagnostic clues. Distinguishing between the different GD types has important therapeutic implications. Currently there are limited treatment options specifically for neuronopathic GD due to the difficulty in delivering therapies across the blood-brain barrier. In this work, we present both classic and newly appreciated aspects of the Gaucher phenotype that can aid in discriminating between acute and chronic neuronopathic GD, and highlight the continuing therapeutic challenges.

High risk screening for Gaucher disease in patients with splenomegaly and/or thrombocytopenia in China: 55 cases identified

Gaucher disease (GD) is a common lysosomal storage disorder caused by deficiency of glucocerebrosidase (GCase) due to the pathogenic variants in the GBA gene. The aim of this study was to evaluate the performance of high risk screening program for GD by measuring the enzyme activities of GCase and chitotriosidease in dried blood spots of patients with splenomegaly and/or thrombocytopenia. A total of 787 subjects (364 females and 423 males) with unexplained splenomegaly and/or thrombocytopenia were enrolled in this study from May 2016 to Aug 2019. The cutoff value of GCase activity was set as less than 3.0 pmol/punch/h for screening positive. The diagnosis of GD was confirmed by Sanger sequencing of the GBA gene. Among 131 screening positive cases, 49 patients were confirmed GD. The positive predictive value was 37.4%.Three patients with boundary values (GCase 3-4 pmol/punch/h) and other three splenectomic patients with normal GCase activity were confirmed GD by GBA genetic analysis because of increased chitotriosidase or Gaucher cells in bone marrow. A total of 55 GD cases were identified. The sensitivity and specificity of the high risk screening were 98.2% and 89.5%, respectively. These 55 GD patients presented splenomegaly (100%), hepatomegaly (70.9%), thrombocytopenia (83.6%). The level of GCase in GD patients was (1.7 ± 1.6) pmol/punch/h. The increased chitotriosidase (383.8 ± 130.2 pmol/punch/h) was found in 42 (76.4%) patients with GD. Molecular genetic analysis identified 44 variants in the GBA gene, including 11 novel variants. The results showed the high risk screening for GD is accurate, rapid and cost-effective.