Fabry disease (FD) is a rare X-linked disorder of glycosphingolipid metabolism caused by pathogenic variants within the alpha-galactosidase A (GLA) gene, often leading to neurological manifestations including stroke. Multiple screening programs seeking GLA variants among stroke survivors lacked detailed phenotype description, making the interpretation of the detected variant's pathogenicity difficult. Here, we describe detailed clinical characteristics of GLA variant carriers identified by a nationwide stroke screening program in the Czech Republic. A total of 23 individuals with 8 different GLA variants were included in the study. A comprehensive diagnostic workup was performed by a team of FD specialists. The investigation led to the suggestion of phenotype reclassification for the G325S mutation from late-onset to classical. A novel variant R30K was found and was classified as a variant of unknown significance (VUS). The typical manifestation in our FD patients was a stroke occurring in the posterior circulation with an accompanying pathological finding in the cerebrospinal fluid. Moreover, we confirmed that cornea verticillata is typically associated with classical variants. Our findings underline the importance of detailed phenotype description and data sharing in the correct identification of pathogenicity of gene variants detected by high-risk-population screening programs.

• Klíčová slova
• Fabry disease, GLA gene variants, data sharing, phenotype, screening programs, stroke,
• Publikační typ
• časopisecké články MeSH

We have identified 21 different alpha-galactosidase A gene (GLA) mutations in 22 unrelated Czech and Slovak families with Fabry disease. Eleven of these mutations were novel (point mutations D93N, A135V, D155H, G171R, Q280K, G360S, Q330X, splicing errors c.194ins14, c.801ins36 and deletions c.674_732del59, g.3405_6021del2617). Genotyping of family members for family-specific mutations revealed 55 heterozygotes that manifested clinical symptoms of different severity. To examine the contribution of X-inactivation skewing to disease manifestation in Fabry heterozygotes, we have adopted the Mainz severity scoring scheme and compared the score values with the X-inactivation status in 39 carriers in an age-dependent manner. The age-score trendline of Fabry females who had a predominantly inactivated X-chromosome bearing a wild-type GLA allele (10 of 38 females) was markedly steeper than in the rest of the cohort. One female carrier with an inactivated mutated allele had a low score value when compared to the other heterozygotes of the same age. These data suggest that X-inactivation is indeed a major factor determining the severity of clinical involvement in Fabry heterozygotes. There was a statistically significant difference between the severity score values of heterozygotes with random and non-random X-chromosome inactivation at the 5% level of significance. Further studies will show if the degree of the wildtype allele inactivation will be useful as a predictive marker of severity of phenotype in Fabry heterozygotes. Although the correlation between X-inactivation skewing and presentation of the disease in Fabry heterozygotes has previously been suggested in the literature, this report is among the first attempts to examine this relationship systematically.

• MeSH
• alfa-galaktosidasa genetika   MeSH
• bodová mutace MeSH
• dítě MeSH
• dospělí MeSH
• Fabryho nemoc epidemiologie   genetika   MeSH
• genetické nemoci vázané na chromozom X * MeSH
• heterozygot MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• stupeň závažnosti nemoci MeSH
• umlčování genů * MeSH
• věkové faktory MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Slovenská republika epidemiologie   MeSH
• Názvy látek
• alfa-galaktosidasa MeSH

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by pathogenic variants in the α-galactosidase A (GLA) gene that leads to reduced or undetectable α-galactosidase A enzyme activity and progressive accumulation of globotriaosylceramide and its deacylated form globotriaosylsphingosine in cells throughout the body. FD can be multisystemic with neurological, renal, cutaneous and cardiac involvement or be limited to the heart. Cardiac involvement is characterized by progressive cardiac hypertrophy, fibrosis, arrhythmias, heart failure and sudden cardiac death. The cardiac management of FD requires specific measures including enzyme replacement therapy or small pharmacological chaperones in patients carrying amenable pathogenic GLA gene variants and more general management of cardiac symptoms and complications. In this paper, we summarize current knowledge of FD-related heart disease and expert consensus recommendations for its management.

• Klíčová slova
• Cardiomyopathy, Enzyme replacement therapy, Fabry disease, GLA gene,
• MeSH
• alfa-galaktosidasa genetika   MeSH
• enzymová substituční terapie MeSH
• Fabryho nemoc * komplikace   genetika   terapie   MeSH
• konsensus MeSH
• lidé MeSH
• srdeční selhání * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alfa-galaktosidasa MeSH

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the GLA gene encoding alpha-galactosidase A (AGAL). The impact of X-chromosome inactivation (XCI) on the phenotype of female FD patients remains unclear. In this study we aimed to determine pitfalls of XCI testing in a cohort of 35 female FD patients. XCI was assessed by two methylation-based and two allele-specific expression assays. The results correlated, although some variance among the four assays was observed. GLA transcript analyses identified crossing-over in three patients and detected mRNA instability in three out of four analyzed null alleles. AGAL activity correlated with XCI pattern and was not influenced by the mutation type or by reduced mRNA stability. Therefore, AGAL activity may help to detect crossing-over in patients with unstable GLA alleles. Tissue-specific XCI patterns in six patients, and age-related changes in two patients were observed. To avoid misinterpretation of XCI results in female FD patients we show that (i) a combination of several XCI assays generates more reliable results and minimizes possible biases; (ii) correlating XCI to GLA expression and AGAL activity facilitates identification of cross-over events; (iii) age- and tissue-related XCI specificities of XCI patterning should be considered.

• Klíčová slova
• Fabry disease heterozygotes, GLA transcript expression, X chromosome inactivation assay, alpha-galactosidase A activity,
• MeSH
• alfa-galaktosidasa genetika   MeSH
• chromozomy MeSH
• Fabryho nemoc * diagnóza   genetika   MeSH
• fenotyp MeSH
• inaktivace chromozomu X genetika   MeSH
• lidé MeSH
• mutace MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alfa-galaktosidasa MeSH

BACKGROUND AND AIMS: Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by disease-associated variants in the alpha-galactosidase A gene (GLA). FD is a known cause of stroke in younger patients. There are limited data on prevalence of FD and stroke risk in unselected stroke patients. METHODS: A prospective nationwide study including 35 (78%) of all 45 stroke centers and all consecutive stroke patients admitted during three months. Clinical data were collected in the RES-Q database. FD was diagnosed using dried blood spots in a stepwise manner: in males-enzymatic activity, globotriaosylsphingosine (lyso-Gb3) quantification, if positive followed by GLA gene sequencing; and in females GLA sequencing followed by lyso-Gb3. RESULTS: 986 consecutive patients (54% men, mean age 70 years) were included. Observed stroke type was ischemic 79%, transient ischemic attack (TIA) 14%, intracerebral hemorrhage (ICH) 7%, subarachnoid hemorrhage 1% and cerebral venous thrombosis 0.1%. Two (0.2%, 95% CI 0.02-0.7) patients had a pathogenic variant associated with the classical FD phenotype (c.1235_1236delCT and p.G325S). Another fourteen (1.4%, 95% CI 0.08-2.4) patients had a variant of GLA gene considered benign (9 with p.D313Y, one p.A143T, one p.R118C, one p.V199A, one p.R30K and one p.R38G). The index stroke in two carriers of disease-associated variant was ischemic lacunar. In 14 carriers of GLA gene variants 11 strokes were ischemic, two TIA, and one ICH. Patients with positive as compared to negative GLA gene screening were younger (mean 60±SD, min, max, vs 70±SD, min, max, P = 0.02), otherwise there were no differences in other baseline variables. CONCLUSIONS: The prevalence of FD in unselected adult patients with acute stroke is 0.2%. Both patients who had a pathogenic GLA gene variant were younger than 50 years. Our results support FD screening in patients that had a stroke event before 50 years of age.

• MeSH
• alfa-galaktosidasa krev   genetika   MeSH
• cévní mozková příhoda krev   komplikace   epidemiologie   genetika   MeSH
• exprese genu MeSH
• Fabryho nemoc krev   komplikace   epidemiologie   genetika   MeSH
• genetické testování MeSH
• glykolipidy krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace MeSH
• prevalence MeSH
• prospektivní studie MeSH
• senioři MeSH
• sfingolipidy krev   MeSH
• test suché kapky krve MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• alfa-galaktosidasa MeSH
• GLA protein, human MeSH Prohlížeč
• globotriaosyl lysosphingolipid MeSH Prohlížeč
• glykolipidy MeSH
• sfingolipidy MeSH

We present two sisters with a severe form of Fabry disease, who both carry the same mutation in the alpha-galactosidase A (alpha-gal A) gene (Q330X). Each of the sisters developed renal failure in the third decade of life; the older sibling underwent renal transplantation at 40 years of age. The severe phenotype of the siblings correlates with results of the X-inactivation study: examination of methylation status in human androgene receptor (HUMARA) gene suggests preferential inactivation of the wild-type allele in both patients. Patients' parents had no symptoms of Fabry disease and were tested negative for the mutation Q330X in DNA isolated from peripheral leukocytes, mouth wash cells, and urinary sediment cells. Genotype analysis using DXS7424 marker showed paternal origin of the mutation. The father's sperm was then tested for presence of the mutation to examine the possibility of the germline mosaicism. Both mutant and wild-type alleles were found in DNA isolated from father's sperm. The apparent explanation of these findings is germline mosaicism due to mutation event during the embryonic development of sperm producing cells (spermatogonia). This is the first case of germline mosaicism in Fabry disease reported in the literature.

• MeSH
• alfa-galaktosidasa genetika   metabolismus   MeSH
• androgenní receptory genetika   MeSH
• dospělí MeSH
• Fabryho nemoc enzymologie   genetika   MeSH
• kompenzace dávky (genetika) MeSH
• lidé MeSH
• mozaicismus * MeSH
• rodokmen MeSH
• zárodečné mutace genetika   MeSH
• zdraví rodiny MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alfa-galaktosidasa MeSH
• androgenní receptory MeSH

The zebrafish (Danio rerio) genome contains a single gene fads2 encoding a desaturase (FADS2) with both Δ6 and Δ5 activities, the key player in the endogenous biosynthesis of long-chain polyunsaturated fatty acids (LC-PUFAs), which serve essential functions as membrane components, sources of energy and signaling molecules. LC-PUFAs include the precursors of eicosanoids and are thus predicted to be indispensable molecules for reproductive health in virtually all vertebrates. In mice, an amniotic vertebrate, fads2 deletion mutants, both males and females, have been confirmed to be sterile. In anamniotic vertebrates, such as fish, there is still no information available on the reproductive (in)ability of fads2 mutants, although zebrafish have become an increasingly important model of lipid metabolism, including some aspects of the generation of germ cells and early embryonic development. In the present study, we apply the CRISPR/Cas9 genome editing system to induce mutations in the zebrafish genome and create crispants displaying a degree of fads2 gene editing within the range of 50-80%. Focusing on adult G0 crispant females, we investigated the LC-PUFA profiles of eggs. Our data suggest an impaired pathway of the LC-PUFA biosynthesis of the ω6 and ω3 series in the first-rate limiting steps of the conversion of linoleic acid (LA) into γ-linolenic acid (GLA), and α-linolenic acid (ALA) into stearidonic acid (SDA), respectively, finally resulting in bad-quality eggs. Our data suggest the existence of an alternative Δ8 pathway, which bypasses the first endogenous LC-PUFA biosynthetic step in zebrafish in vivo, and suggest that the zebrafish bifunctional FADS2 enzyme is actually a trifunctional Δ6/Δ5/Δ8 desaturase.

• Klíčová slova
• CRISPR/Cas9, dihomo γ-linolenic acid (DGLA), fads2, long-chain polyunsaturated (LC-PUFAs) biosynthesis, zebrafish (Danio rerio) reproduction, Δ6/Δ5/Δ8 desaturase,
• MeSH
• dánio pruhované * genetika   metabolismus   MeSH
• desaturasy mastných kyselin * genetika   MeSH
• genový knockout MeSH
• mastné kyseliny MeSH
• myši knockoutované MeSH
• myši MeSH
• rozmnožování genetika   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• desaturasy mastných kyselin * MeSH
• mastné kyseliny MeSH

BACKGROUND: Anderson-Fabry disease (AFD) is an X-linked inherited lysosomal disease caused by a defect in the gene encoding lysosomal enzyme α-galactosidase A (GLA). Atrio-ventricular (AV) nodal conduction defects and sinus node dysfunction are common complications of the disease. It is not fully elucidated how frequently AFD is responsible for acquired AV block or sinus node dysfunction and if some AFD patients could manifest primarily with spontaneous bradycardia in general population. The purpose of study was to evaluate the prevalence of AFD in male patients with implanted permanent pacemaker (PM). METHODS: The prospective multicentric screening in consecutive male patients between 35 and 65 years with implanted PM for acquired third- or second- degree type 2 AV block or symptomatic second- degree type 1 AV block or sinus node dysfunction was performed. RESULTS: A total of 484 patients (mean age 54 ± 12 years at time of PM implantation) were enrolled to the screening in 12 local sites in Czech Republic. Out of all patients, negative result was found in 481 (99%) subjects. In 3 cases, a GLA variant was found, classified as benign: p.Asp313Tyr, p.D313Y). Pathogenic GLA variants (classical or non-classical form) or variants of unclear significance were not detected. CONCLUSION: The prevalence of pathogenic variants causing AFD in a general population sample with implanted permanent PM for AV conduction defects or sinus node dysfunction seems to be low. Our findings do not advocate a routine screening for AFD in all adult males with clinically significant bradycardia.

• Klíčová slova
• Bradycardia, Fabry disease, Permanent pacing, Screening,
• MeSH
• atrioventrikulární blokáda * diagnóza   epidemiologie   terapie   MeSH
• bradykardie komplikace   terapie   MeSH
• dospělí MeSH
• Fabryho nemoc * diagnóza   epidemiologie   genetika   MeSH
• kardiostimulátor * škodlivé účinky   MeSH
• lidé středního věku MeSH
• lidé MeSH
• prospektivní studie MeSH
• senioři MeSH
• syndrom chorého sinu diagnóza   epidemiologie   terapie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH

CONTEXT: Fabry disease is a rare X-linked genetic disease due to pathogenic variants in the GLA gene. Classic Fabry disease is characterized by glycosphingolipids accumulation in all organs including the kidney, resulting in end-stage renal disease in a subset of male patients. Fabry disease should therefore be considered in the differential diagnosis of patients with unexplained end-stage renal disease. OBJECTIVE: We performed a prospective screening study in Western France to determine the prevalence of Fabry disease in a large population of dialyzed and transplanted patients. PATIENTS AND METHODS: Patients meeting the inclusion criteria (males, 18-70 years with end-stage renal disease of unknown or vascular origin) were selected from the REIN® registry and the CRISTAL® database. Screening on filter papers was performed after patient consent was obtained during either a dialysis session or a transplantation follow-up visit. RESULTS: One thousand five hundred and sixty-one end-stage renal disease male patients were screened and 819 consented (dialysis: n=242; transplant: n=577). One single patient was found with decreased alpha-galactosidase levels <25%. GLA sequencing identified the p.Phe113Leu variant in favor of an unknown superimposed kidney disease responsible for end-stage renal disease since this GLA pathogenic variant is associated with a later-onset cardiac form of Fabry disease with minimal kidney involvement. Family cascade genotyping revealed a previously undiagnosed affected brother. CONCLUSION: The prevalence of Fabry disease in end-stage renal disease patients was 0.12%, questioning the efficacy of this screening strategy with respect to the low prevalence. However, beside the benefit for the patient and his family, the increased awareness of Fabry disease among participating nephrologists may be of interest for future patients.

• Klíčová slova
• Dialysis, Dried blood spot, End-stage renal disease, Fabry disease, Transplantation,
• MeSH
• alfa-galaktosidasa genetika   MeSH
• chronické selhání ledvin * diagnóza   epidemiologie   etiologie   MeSH
• dialýza ledvin MeSH
• Fabryho nemoc * komplikace   diagnóza   epidemiologie   MeSH
• lidé MeSH
• prospektivní studie MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alfa-galaktosidasa MeSH

BACKGROUND: Fabry disease (FD) is an X-linked lysosomal storage disease resulting from pathogenic variants in the GLA gene coding α-galactosidase A (AGAL) and cleaving terminal alpha-linked galactose. Globotriaosylceramide (Gb3) is the predominantly accumulated sphingolipid. Gb3, deacylated-Gb3 (lysoGb3), and methylated-Gb3 (metGb3) have been suggested as FD biomarkers. MATERIALS AND METHODS: We developed a novel LC-MS/MS method for assessing lysoGb3 levels in plasma and Gb3 and metGb3 in urine and tested 62 FD patients, 34 patients with GLA variants of unknown significance (VUS) and 59 healthy controls. AGAL activity in white blood cells (WBCs) and plasma was evaluated in parallel. RESULTS: In males, lysoGb3 concentrations in plasma separated classic and late-onset FD patients from each other and from individuals carrying GLA VUS and healthy controls. Calculating AGAL activity/plasmatic lysoGb3 ratio allowed to correctly categorize all females with classic and majority of patients with late-onset FD phenotypes. Correlation of AGAL activity in WBCS with lipid biomarkers identified threshold activity values under which the biomarkers' concentrations increase. CONCLUSION: We developed a novel simplified LC-MS/MS method for quantitation of plasma lysoGb3. AGAL activity/plasma lysoGb3 ratio was identified as the best predictor for FD. AGAL activity correlated with plasma lysoGb3 and corresponded to individual FD phenotypes.

• Klíčová slova
• Diagnostics, Fabry disease, Globotriaosylsphingosine, Lysosomal storage, Mass spectrometry, Phenotype,
• MeSH
• alfa-galaktosidasa genetika   metabolismus   MeSH
• biologické markery krev   MeSH
• chromatografie kapalinová MeSH
• dospělí MeSH
• Fabryho nemoc * krev   diagnóza   moč   MeSH
• fenotyp MeSH
• glykolipidy krev   moč   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• senioři MeSH
• sfingolipidy * krev   MeSH
• tandemová hmotnostní spektrometrie * MeSH
• trihexosylceramidy metabolismus   krev   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alfa-galaktosidasa MeSH
• biologické markery MeSH
• globotriaosyl lysosphingolipid MeSH Prohlížeč
• globotriaosylceramide MeSH Prohlížeč
• glykolipidy MeSH
• sfingolipidy * MeSH
• trihexosylceramidy MeSH