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Hematologists are frequently involved in the diagnostic pathway of Gaucher disease type 1 (GD1) patients since they present several hematological signs. However, GD1 is mainly underdiagnosed because of a lack of awareness. In this multicenter study, we combine the use of a diagnostic algorithm with a simple test (β-glucosidase activity on Dried Blood Spot) in order to facilitate the diagnosis in a population presenting to the hematologist with splenomegaly and/or thrombocytopenia associated with other hematological signs. In this high-risk population, the prevalence of GD1 is 3.3%. We propose an equation that predicts the probability of having GD1 according to three parameters that are routinely evaluated: platelet count, ferritin, and transferrin saturation.

A new patient with severe mucopolysaccharidosis (MPS) type VII is reported. Non-immune hydrops fetalis (NIHF) was diagnosed during pregnancy. At birth, he showed generalized hydrops and dysmorphic features typical of MPS. Many diagnoses were excluded before reaching the diagnosis of MPS VII at 8 months of life. During the first year of life he had frequent respiratory infections associated with restrictive and obstructive bronchopneumopathy and underwent three surgical interventions: decompression of the spinal cord at the craniocervical junction, bilateral inguinal hernia, and bilateral clubfoot. At 14 months of life he underwent successful haematopoietic cell transplantation (HCT). During the following 10 months, his bronchopneumopathy progressively worsened, needing chronic pharmacological treatment and O2 administration. The patient died of respiratory insufficiency during a respiratory syncytial virus infection at 25 months of age. Molecular analysis showed the homozygous variant c.1617C > T, leading to the synonymous mutation p.Ser539=. This caused aberrant splicing with partial skipping of exon 10 (r.1616-1653del38) and complete skipping of exon 9 (r.1392-1476del85; r.1616-1653del38). No transcript of normal size was evident. The parents were both confirmed to be carriers. In a subsequent pregnancy, a prenatal diagnosis showed an affected fetus. Ultrasound examination before abortion showed NIHF. The skin and placenta examination by electron microscopy showed foamy intracytoplasmic vacuoles with a weakly electron-dense substrate. MPS VII is a very rare disease but it is possible that some cases go undiagnosed for several reasons, including that MPS VII, and other lysosomal storage diseases, are not included in the work-up for NIHF in many institutions, and the presence of anasarca at birth may be confounding for the recognition of the typical facial characteristics of the disease. This is the eighth patient affected by MPS VII who has undergone HCT. It is not possible to draw conclusions about the efficacy of HCT in MPS VII. Treatment with enzyme replacement is now available and will probably be beneficial for the patients who have a milder form with no or little cognitive involvement. Increased awareness among clinicians is needed for prompt diagnosis and to offer the correct treatment as early as possible.

Morquio A syndrome (MPS IVA) is a systemic lysosomal storage disorder caused by the deficiency of N-acetylgalactosamine-6-sulfatase (GALNS), encoded by the GALNS gene. We studied 37 MPS IV A patients and defined genotype-phenotype correlations based on clinical data, biochemical assays, molecular analyses, and in silico structural analyses of associated mutations. We found that standard sequencing procedures, albeit identifying 14 novel small GALNS genetic lesions, failed to characterize the second disease-causing mutation in the 16% of the patients' cohort. To address this drawback and uncover potential gross GALNS rearrangements, we developed molecular procedures (CNV [copy-number variation] assays, QF-PCRs [quantitative fluorescent-PCRs]), endorsed by CGH-arrays. Using this approach, we characterized two new large deletions and their corresponding breakpoints. Both deletions were heterozygous and included the first exon of the PIEZO1 gene, which is associated with dehydrated hereditary stomatocitosis, an autosomal-dominant syndrome. In addition, we characterized the new GALNS intronic lesion c.245-11C>G causing m-RNA defects, although identified outside the GT/AG splice pair. We estimated the occurrence of the disease in the Italian population to be approximately 1:300,000 live births and defined a molecular testing algorithm designed to help diagnosing MPS IVA and foreseeing disease progression. © 2014 WILEY PERIODICALS, INC.

CONTEXT: High-mobility group A1 (HMGA1) protein is a key regulator of insulin receptor (INSR) gene expression. We previously identified a functional HMGA1 gene variant in 2 insulin-resistant patients with decreased INSR expression and type 2 diabetes mellitus (DM). OBJECTIVE: To examine the association of HMGA1 gene variants with type 2 DM. DESIGN, SETTINGS, AND PARTICIPANTS: Case-control study that analyzed the HMGA1 gene in patients with type 2 DM and controls from 3 populations of white European ancestry. Italian patients with type 2 DM (n = 3278) and 2 groups of controls (n = 3328) were attending the University of Catanzaro outpatient clinics and other health care sites in Calabria, Italy, during 2003-2009; US patients with type 2 DM (n = 970) were recruited in Northern California clinics between 1994 and 2005 and controls (n = 958) were senior athletes without DM collected in 2004 and 2009; and French patients with type 2 DM (n = 354) and healthy controls (n = 50) were enrolled at the University of Reims in 1992. Genomic DNA was either directly sequenced or analyzed for specific HMGA1 mutations. Messenger RNA and protein expression for HMGA1 and INSR were measured in both peripheral lymphomonocytes and cultured Epstein-Barr virus-transformed lymphoblasts from patients with type 2 DM and controls. MAIN OUTCOME MEASURES: The frequency of HMGA1 gene variants among cases and controls. Odds ratios (ORs) for type 2 DM were estimated by logistic regression analysis. RESULTS: The most frequent functional HMGA1 variant, IVS5-13insC, was present in 7% to 8% of patients with type 2 DM in all 3 populations. The prevalence of IVS5-13insC variant was higher among patients with type 2 DM than among controls in the Italian population (7.23% vs 0.43% in one control group; OR, 15.77 [95% confidence interval {CI}, 8.57-29.03]; P < .001 and 7.23% vs 3.32% in the other control group; OR, 2.03 [95% CI, 1.51-3.43]; P < .001). In the US population, the prevalence of IVS5-13insC variant was 7.7% among patients with type 2 DM vs 4.7% among controls (OR, 1.64 [95% CI, 1.05-2.57]; P = .03). In the French population, the prevalence of IVS5-13insC variant was 7.6% among patients with type 2 DM and 0% among controls (P = .046). In the Italian population, 3 other functional variants were observed. When all 4 variants were analyzed, HMGA1 defects were present in 9.8% of Italian patients with type 2 DM and 0.6% of controls. In addition to the IVS5 C-insertion, the c.310G>T (p.E104X) variant was found in 14 patients and no controls (Bonferroni-adjusted P = .01); the c.*82G>A variant (rs2780219) was found in 46 patients and 5 controls (Bonferroni-adjusted P < .001); the c.*369del variant was found in 24 patients and no controls (Bonferroni-adjusted P < .001). In circulating monocytes and Epstein-Barr virus-transformed lymphoblasts from patients with type 2 DM and the IVS5-13insC variant, the messenger RNA levels and protein content of both HMGA1 and the INSR were decreased by 40% to 50%, and these defects were corrected by transfection with HMGA1 complementary DNA. CONCLUSIONS: Compared with healthy controls, the presence of functional HMGA1 gene variants in individuals of white European ancestry was associated with type 2 DM.

Multiple sulfatase deficiency (MSD) is a rare disorder characterized by impaired activity of all known sulfatases. The gene mutated in this disease is SUMF1, which encodes a protein involved in a post-translational modification at the catalytic site of all sulfatases that is necessary for their function. SUMF1 strongly enhances the activity of sulfatases when coexpressed with sulfatase in Cos-7 cells. We performed a mutational analysis of SUMF1 in 20 MSD patients of different ethnic origin. The clinical presentation of these patients was variable, ranging from severe neonatal forms to mild phenotypes showing mild neurological involvement. A total of 22 SUMF1 mutations were identified, including missense, nonsense, microdeletion, and splicing mutations. We expressed all missense mutations in culture to study their ability to enhance the activity of sulfatases. Of the predicted amino acid changes, 11 (p.R349W, p.R224W, p.L20F, p.A348P, p.S155P, p.C218Y, p.N259I, p.A279V, p.R349Q, p.C336R, p.A177P) resulted in severely impaired sulfatase-enhancing activity. Two (p.R345C and p.P266L) showed a high residual activity on some, but not all, of the nine sulfatases tested, suggesting that some SUMF1 mutations may have variable effects on the activity of each sulfatase. This study compares, for the first time, clinical, biochemical, and molecular data in MSD patients. Our results show lack of a direct correlation between the type of molecular defect and the severity of phenotype.

Fabry disease (FD) is an X-linked lysosomal storage disorder (LSD) caused by the deficiency of the enzyme α-galactosidase. It exhibits a wide clinical spectrum that may lead to a delayed or even missed diagnosis and the real incidence can be underestimated. We report the cases of two unrelated Italian families in whom FD was incidentally diagnosed in two females. In both families, the risk for other lysosomal disorders was known from other members affected by fucosidosis or mucopolysaccharidosis I Hurler/Scheie. Some subjects were simultaneously heterozygous for Fabry and the other lysosomal deficiency. Our study shows that the risk for more than one LSDs can occur in a family pedigree. The diagnosis of Fabry in female probands represents a diagnostic challenge, as symptoms and signs can be variably present because of the random X-chromosome inactivation.

Krabbe leukodystrophy (KD) is a neurodegenerative lysosomal disorder caused by mutations in the galactocerebrosidase (GALC) gene. Different clinical forms are described based on the age at onset. In reported series, the early infantile form (EIKD) accounts for more than 90% of the cases. The rarer late onset forms (LOKD) become manifest later than 6 months up to the adult age. We report clinical, imaging, mutational analysis and geographic data in a large cohort of individuals with Krabbe disease examined over a 30-year period. Retrospective analyses of disease onset and long-term follow-up were conducted in 26 KD patients. Molecular analysis was performed in 12 patients and their families. Nine cases had EIKD, and 17 LOKD, accounting for two thirds of our series. No correlation was found between enzymatic activity, onset age and disease progression. Despite common geographical origin, only in a few cases could parental consanguinity be proven. The p.Gly41Ser mutation was associated with longer survival. A wide spectrum of LOKD is found despite similar genotype. Although current knowledge about onset age, residual enzyme activity and molecular analysis still fail to allow the identification of patient candidates for treatment, this information is valuable for long-term outcome prediction and could lead to reconsideration of inclusion criteria for bone marrow transplant (BMT) or other future therapeutic approaches.