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Gaucher disease (GD) is a common lysosomal storage disorder caused by the deficiency of acid β-glucosidase, due to mutations in the GBA gene. To explore the clinical and molecular characteristics of GD patients from Southern China, GBA gene were analyzed by nest PCR and direct Sanger-sequencing. Novel missense mutations were transiently transfected in COS-7 cells by plasmid system for functional verification. Among the 22 GD patients, 19 patients were classified as type 1 and three as type 2. Over 60% of the type 1 patient had the onset before two years of age and about 42% of them died before three years of age. Six type 1 patients with L444P homozygous genotype, presented with early onset and severe hepatosplenomegaly. Four novel mutations Y22C, F109L, L149F and c.983_990delCCCACTGG were identified. The GBA activities in vitro of novel mutants Y22C, F109L and L149F were 20.2%, 6.9% and 6.5% of the wild-type, respectively. L444P mutation accounted for 47.7% of the mutant alleles. Our results revealed that type 1 GD tends to present with a severe phenotype among southern Chinese. L444P was the most prevalent mutation and L444P homozygous genotype was associated with severe type 1 GD. Three novel missense mutations identified were pathogenic., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Gaucher disease is the most prevalent inherited disorder among Ashkenazi Jews (carrier frequency of about 6%) and six mutations account for about 96% of their mutant alleles. Two mutations, N370S and R496H, have been reported only in mildly affected or asymptomatic patients. Due to the rarity of R496H, it was recommended that it be excluded from screening programs., Objectives: To verify the frequency and trace the origin of Gaucher mutations in screened individuals whose Ashkenazi ethnicity was confirmed by the birthplace of their grandparents., Methods: We conducted a retrospective analysis of the screened results for the period 2006-2011. Mutations were identified by restriction analysis, Tag-It detection system, Pronto diagnostic kit and Nanogen technology (NanoChip 400)., Results: The heterozygote frequency of eight mutations was estimated in a cohort of 16,910 alleles. Two mutations, N370S and R496H, were the most frequent in our population. However, while the occurrence of N370S carriers was similar to other reports (1:19.4), that of R496H carriers was considerably elevated (1:207). Examination of the screened individuals' ethnicity showed a significant difference in the distribution pattern of the country of origin between the carriers of these two mutations., Conclusions: The origin pattern differences between the two groups of heterozygotes might reflect a separate geographic region of introduction for various mutations. As a result, secondary subgroups could be formed within the Ashkenazi population. This might clarify the dissimilarities in the occurrence of R496H mutation reported by various centers.

Objective: To review and investigate the relationship of genotype and phenotype in Chinese patients with Gaucher disease (GD)., Methods: The samples were first screened for known mutations as reported previously in Chinese population. Long chain PCR and nested PCR were employed to amplify the segments of glucocerebrosidase functional gene in patients with unknown mutant alleles. The products of nested-PCR were subjected to DNA sequencing to detect the new mutations., Results: Forty kinds of mutations were detected in this panel of patients. The L444P mutation was the most common one accounting for 33.0% of mutant alleles. It was followed by F213I, N188S, V375L and M416V., Conclusion: There are at least 40 mutations in Chinese GD patients. The spectrum of mutation is significantly different from that in Caucasians. 70% of mutant alleles have been characterized. It becomes feasible to make clinical and prenatal diagnoses through gene analysis.

A body of work has emerged over the past decade demonstrating a relationship between mutations in glucocerebrosidase gene (GBA), the gene implicated in Gaucher disease (GD), and the development of parkinsonism. Several different lines of research support this relationship. First, patients with GD who are homozygous for mutations in GBA have a higher than expected propensity to develop Parkinson's disease (PD). Furthermore, carriers of GBA mutations, particularly family members of patients with GD, have displayed an increased rate of parkinsonism. Subsequently, investigators from centers around the world screened cohorts of patients with parkinsonism for GBA mutations and found that overall, subjects with PD, as well as other Lewy body disorders, have at least a fivefold increase in the number of carriers of GBA mutations as compared to age-matched controls. In addition, neuropathologic studies of subjects with parkinsonism carrying GBA mutations demonstrate Lewy bodies, depletion of neurons of the substantia nigra, and involvement of hippocampal layers CA2-4. Although the basis for this association has yet to be elucidated, evidence continues to support the role of GBA as a PD risk factor across different centers, synucleinopathies, and ethnicities. Further studies of the association between GD and parkinsonism will stimulate new insights into the pathophysiology of the two disorders and will prove crucial for both genetic counseling of patients and family members and the design of relevant therapeutic strategies for specific patients with parkinsonism., (2009 Movement Disorder Society.)

Gaucher disease is the most common lysosomal storage disorder, it results from the inherited deficiency of the enzyme glucocerebrosidase, the accumulation of its substrate causes many clinical manifestations. Since the discovery of GBA gene, more than 200 different mutations have been identified, but only handful mutations are recurrent (N370S, L444P and c.84insG). In order to determine the mutation spectrum in Tunisia, we performed recurrent mutation screening in ten unrelated Tunisian children with Gaucher disease. Screening of recurrent mutation by PCR/RFLP and direct sequencing, has shown that N370S is the most frequent mutation (6/20 mutant alleles, 30%), followed by recombinant allele (RecNciI) which is found in five patients (5/20 mutant alleles, 25%), the L444P mutation represent 20% (4/20 mutant alleles). Our findings revealed that five among ten studied patients, were compound heterozygous N370S/RecNciI (50%). The screening of these mutations provides a simple tool for molecular diagnosis of Gaucher disease in Tunisian patients and allows also genetic counselling for their family members.

Gaucher disease is an autosomal recessive disorder caused by mutations in the lysosomal beta-glucocerebrosidase (GBA) gene. Gaucher disease is a very heterogeneous entity due to the large number of different mutations existing in the GBA gene, resulting in a defective protein whose impaired activity is the cause of the disease. We present a mutation analysis of the GBA gene in 51 unrelated Spanish Gaucher disease patients together with clinical findings. Two common mutations, c.1226A>G (N370S) and c.1448T>C (L444P), were determined by restriction enzyme digestion after PCR amplification of genomic DNA. The remaining alleles were screened by amplifying the entire GBA gene followed by nested PCR and SSCP analysis under four different conditions. The c.1226A>G (N370S) and c.1448T>C (L444P) mutations were common, accounting for 56 alleles (55%) and 16 alleles (15%), respectively. In addition, 25 different mutations were found, 11 of which are described here for the first time: c.(-203)A>G, c.160G>A (V15M), c.256C>T (R47X), c.445-2a>g (IVS4-2a>g), c.485T>C (M123T), c.914C>T (P266L), c.953delT, c.1124T>C (L336P), c.1207A>C (S364R), c.1214delG,C, and c.1510delT,C,T (465delSer). Two mutations, S364R and P266L, were associated with neuronopathic forms of Gaucher disease: S364R mutation in heterozygosity with the L444P mutation and the P266L mutation in a homozygous state. Two type 1 patients were found to be carriers of two mutations in the same allele (genotypes [N370S] + [E326K + N188S] and [N370S] + [IVS4-2a>g+c.(-203)A>G]). This study allowed us to identify 100% of mutant alleles, and therefore we conclude that the method used to screen for mutations in the GBA gene is very reliable and there is a broad spectrum of mutations in the GBA gene in the Spanish population., ((c)2001 Elsevier Science.)

Background: Gaucher disease is an autosomal recessive disorder resulting from mutations in the glucocerebrosidase gene (GBA). The lack of full genotype/phenotype correlation complicates counseling regarding clinical outcome and treatment recommendations., Subjects and Methods: Several mutations in the human beta-glucosidase gene associated with Gaucher disease in 16 Spanish families were identified utilizing a combination of methods: enzymatic restriction, PCR-SSCP, and sequence analyses. Expression studies were performed following the introduction of the mutagenized human acid beta-glucosidase cDNA into COS-1 cells, and the residual enzyme activities of the mutant protein were measured and compared with the normal cDNA., Results: The identified mutations and corresponding residual enzyme activities of the expressed protein are as follows: c.517A>C (T134P), 1%; c.721G>A (G202R), 17%; c.1090G>T (G325W), 13.9%; c.1093G>A (E326K), 26%; c.1208G>A (S364N), 4.1%; c.1226A>G (N370S), 17,8%; c.1246G>A (G377S), 17.6%; c.1289C>T (P391L), 8.5%; c.1448T>C (L444P), 3%; and c.1504C>T (R463C), 24.5%., Conclusions: Site-directed mutagenesis and expression in COS-1 cells are useful methods to increase our understanding of causality in Gaucher disease and the correlation between disease severity, gene defects, and residual enzyme activity. Our study demonstrates the functional consequences of the identified human beta-glucosidase mutations (T134P, S364N, G377S, P391L, and G325W) and provide evidence for the molecular and biochemical basis of Gaucher disease, among patients of Spanish ancestry., (Copyright 2001 Academic Press.)

The N370S mutation at the GBA locus on human chromosome 1q21, which causes Gaucher disease (GD), has a high frequency in the Ashkenazim and is the second-most-widespread GD mutation in the European non-Jewish population. A common ancient origin for the N370S mutation in the Ashkenazi Jewish and Spanish populations has been proposed on the basis of both a similar haplotype for associated markers and an age estimate that suggests that this mutation appeared several thousand years ago. However, a reappraisal of haplotype data, using the Risch formula properly along with a Luria-Delbrück setting of the genetic clock, allows identification of the likely origin of the N370S mutation in Ashkenazi Jews between the 11th and 13th centuries. This result is consistent with the estimated ages of other mutations that are frequent among Ashkenazim, with the exception of type II (Glu117Stop) factor XI deficiency, which is deemed to be >3000 years old, predating the separation of the Ashkenazi and Iraqi Jews. The present finding supports the hypothesis of a more recent origin for the N370S mutation and is consistent with both a founder chromosome transfer from Ashkenazim who assimilated in some European populations and a non-Jewish origin of the European N370S-bearing chromosomes.

Gaucher Disease type 1, the most prevalent lysosomal disease among Caucasians, is due to defects in the activity of acid beta-glucosidase. Over 40 missense, nonsense, and more complex alleles have been described, primarily in Western populations. From these results, predictive genotype/phenotype correlations have been developed and used to guide genetic counseling and therapy. Only a few mutations have been described in Japanese patients with Gaucher disease and many of these have resulted in severe phenotypes. Although rare, Gaucher Disease occurs in Korean and Chinese (Taiwanese) populations. Sequencing of RT-PCR cDNAs from five unrelated Korean and two sibling Chinese (Taiwanese) Gaucher type 1 patients identified three new Gaucher disease mutations. These disease alleles encoded V15L, G46E, and N188S substitutions leading to dysfunctional acid beta-glucosidases. The G46E was present in two Korean patients and the N188S allele was present in the Korean and Chinese (Taiwanese) populations, suggesting an ancient mutation. The commonality of these two mutations in the Korean and Chinese (Taiwanese) population indicates the need for more extensive screening for these mutations in the Gaucher populations.

The prevalence of seven different mutations (84GG, IVS2 + 1, 754A, 1226G, 1342C, 1448C, and 1504T) was investigated in 32 unrelated Japanese Gaucher patients of which 20 were type I, 6 were type II, and 6 were type III). These mutations constitute 95% of the mutations observed in Jewish patients with Gaucher disease and 75% of the mutations in non-Jews (European). The most frequent mutation, 1448C (L444P), accounted for 26 alleles (40.6%); the second most prevalent mutation was 754A (F213I), accounting for 7 alleles (10.9%); 27 alleles (42.2%) were unidentified. To data, neither the 1226G (N370S) nor 84GG mutations have been identified in the Japanese population though these alleles account for approximately 70% and 10% of mutations in the Jewish population. These data suggest that mutant alleles identified from the Japanese population are distinct from those observed in Jewish and non-Jewish (European) patients with Gaucher disease.

Background: Thirty-six mutations that cause Gaucher disease, the most common glycolipid storage disorder, are known. Although both alleles of most patients with the disease contain one of these mutations, in a few patients one or both disease-producing alleles have remained unidentified. Identification of mutations in these patients is useful for genetic counseling., Materials and Methods: The DNA from 23 Gaucher disease patients in whom at least one glucocerebrosidase allele did not contain any of the 36 previously described mutations has been examined by single strand conformation polymorphism (SSCP) analysis, followed by sequencing of regions in which abnormalities were detected., Results: Eight previously undescribed mutations were detected. In exon 3, a deletion of a cytosine at cDNA nt 203 was found. In exon 6, three missense mutations were identified: a C-->A transversion at cDNA nt 644 (Ala176-->Asp), a C-->A transversion at cDNA nt 661 that resulted in a (Pro182-->Thr), and a G-->A transition at cDNA nt 721 (Gly202-->Arg). Two missense mutations were found in exon 7: a G-->A transition at cDNA nt 887 (Arg257-->Gln) and a C-->T at cDNA nt 970 (Arg285-->Cys). Two missense mutations were found in exon 9: a T-->G at cDNA nt 1249 (Trp378-->Gly) and a G-->A at cDNA nt 1255 (Asp380-->Asn). In addition to these disease-producing mutations, a silent C-->G transversion at cDNA nt 1431, occurring in a gene that already contained the 1226G mutation, was found in one family., Conclusions: The mutations described here and previously known can be classified as mild, severe, or lethal, on the basis of their effect on enzyme production and on clinical phenotype, and as polymorphic or sporadic, on the basis of the haplotype in which they are found. Rare mutations such as the new ones described here are sporadic in nature.

Type 1 Gaucher disease families were studied in an attempt to establish a phenotype/genotype correlation in affected persons and also to identify carriers accurately. In the Portuguese type 1 Gaucher patients, screening for mutations N370S, L444P, R463C, and 1066 + 1 G-->A allowed the identification of 85% of the alleles among unrelated patients. A subclinical case with genotype N370S/1066 + 1 G-->A was identified in one family in which there were three other symptomatic sibs. To our knowledge this is the first subclinical case with a genotype other than N370S/N370S. No genotype-phenotype correlation could be established and considerable clinical heterogeneity was found even among sibs with the same genotype. The data collected on the origins of the Gaucher families indicated two areas in northern Portugal where a higher frequency of the disease may be expected to exist.

Glucocerebrosidase is a lysosomal enzyme responsible for hydrolysis of glucosylceramide to ceramide and glucose. Mutations disrupting the function of this enzyme cause autosomal recessive Gaucher disease. This disease is very heterogeneous. The clinical heterogeneity is due to a large number of mutations within the gene encoding glucocerebrosidase. To date 36 mutations have been described in Gaucher disease. In this part we present the mutations and review the more common ones. We also review the glucocerebrosidase natural activator, designated saposin C and mutations in its gene, associated with Gaucher disease.

Reliable estimates of the frequency of Gaucher disease-producing mutations are not available. The high frequency of Gaucher disease in the Ashkenazi Jewish population is due to the occurrence of a mutation at nucleotide (nt) 1226. We have screened 593 DNA samples from normal Ashkenazi Jews, as well as 62 DNA samples from all our Ashkenazi Jewish patients with Gaucher disease, for the presence of the 1226 mutation. In the 593 presumed normal Ashkenazi Jewish individuals the 1226 mutation was identified in the heterozygous state in 37 and in the homozygous state in two, giving a gene frequency of .035 for the mutation. This 1226 mutation represented 73% of the 124 Gaucher disease alleles in Jewish Gaucher disease patients. Accordingly we estimate that the gene frequency for Gaucher disease among the Ashkenazi Jewish population is .047, which is equivalent to a carrier frequency of 8.9% and a birth incidence of 1:450.