Prenatal genotyping of Gaucher disease in Egypt

Clinical and Genetic Varieties of Gaucher Disease in Iraqi Children

Gaucher disease (GD), which is due to a deficiency in the lysosomal enzyme β-glucocerebrosidase, is a rare genetic disorder. It is characterized by a wide variety of clinical manifestations and severity of symptoms, making it difficult to manage. A cross-sectional hospital-based genetic study was undertaken with 32 pediatric patients. We recruited 21 males and 11 females diagnosed with GD, with a male-to-female ratio of 1.91:1. The mean age of the study population was 8.79 ± 4.37 years with an age range from 8 months to 17 years. We included patients on clinical evaluation from 2011 to 2019. An enzyme assay test was used to measure β-glucosidase enzyme activity in leukocytes and the GBA gene study was performed by polymerase chain reaction technique. We found GD type 1 in 27 (84.37%) participants, GD type 3 in five (15.63%) participants, while none classified as GD type 2. The dominant mutation in GD 1 was N370S in 81.5%, of which two-thirds were homozygous. The second common mutation in this type of disease (L444P) was present in nine cases (40.9%), two of whom were homozygous (9.9%). Meanwhile, R463C was present in six cases (27.27%), of whom one was homozygous. In GD 3, the dominant mutation was L444P as seen in 80% of the patients followed by N370S and R463C in 20%. This study shows that the most common mutant allele in this study was N370S, followed by L444P. Further large-scale studies with more advanced designs are recommended to explore the sequences of GBA genes.

Hyperimmunoglobulinemia and IgG Subclass Abnormalities in Children With Gaucher Disease

Gaucher disease (GD) is the most common lysosomal storage disorder, the aim of the current study was to investigate hyperimmunoglobulinemia and abnormalities of serum immunoglobulin G (IgG) subclasses in children with GD and the relation of those findings to the GD phenotype and genotype, duration of enzyme replacement therapy (ERT), and infection frequency. The study included 20 Egyptian children with GD receiving ERT and 20 age-matched and sex-matched healthy children as controls. Serum Ig and serum IgG subclass levels were measured in the children with GD. Serum IgG subclass levels were measured in the control subjects. Hyperimmunoglobulinemia was present in 15 of the 20 (75%) children with GD. In addition, it is found significantly lower IgG2 levels and significantly higher IgG3 levels in the GD group than in the control group (P<0.001 and <0.006, respectively). Patients with 12 infections per year had significantly higher IgG3 levels compared with patients with 6 infections per year (P=0.022). In conclusion, hyperimmunoglobulinemia and IgG subclass abnormalities occur in children with GD who are on ERT and may be related to recurrent infections.