A personalized treatment decision for Gaucher disease (GD) patients should be based on relevant markers that are specific to GD, play a direct role in GD pathophysiology, exhibit low genetic variation, reflect the therapy, and can be used for all patients. Thirty-four GD patients treated with enzyme replacement therapy (ERT) or substrate reduction therapy (SRT) were analyzed for platelet count, chitotriosidase, and tartrate-resistant acid phosphatase activity in plasma samples, and quantitative measurement of Lyso-Gb1 was performed in dried blood spots. In our ERT and SRT study cohorts, plasma lyso-GL1 correlated significantly with chito-triosidase (ERT: r = 0.55, p < 0.001; SRT: r = 0.83, p < 0.001) and TRAP (ERT: r = 0.34, p < 0.001; SRT: r = 0.88, p < 0.001), irrespective of treatment method. A platelet count increase was associated with a Lyso-Gb1 decrease in both treatment groups (ERT: p = 0.021; SRT: p = 0.028). The association of Lyso-Gb1 with evaluated markers was stronger in the SRT cohort. Our results indicate that ERT and SRT in combination or in a switch manner could offer the potential of individual drug effectiveness for particular GD symptoms. Combination of the key biomarker of GD, Lyso-Gb1, with other biomarkers can offer improved response assessment to long-term therapy.

• MeSH
• biologické markery MeSH
• enzymová substituční terapie MeSH
• Gaucherova nemoc * diagnóza   farmakoterapie   MeSH
• lidé MeSH
• počet trombocytů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika 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.

• 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

• Publikační typ
• abstrakt z konference MeSH

Cullin 4B (CUL4B), lysosomal-associated membrane protein Type 2 (LAMP2), ATP1B4, TMEM255A, and ZBTB33 are neighboring genes on Xq24. Mutations in CUL4B result in Cabezas syndrome (CS). Male CS patients present with dysmorphic, neuropsychiatric, genitourinary, and endocrine abnormalities. Heterozygous CS females are clinically asymptomatic. LAMP2 mutations cause Danon disease (DD). Cardiomyopathy is a dominant feature of DD present in both males and heterozygous females. No monogenic phenotypes have been associated with mutations in ATP1B4, TMEM255A, and ZBTB33 genes. To facilitate diagnostics and counseling in CS and DD families, we present a female DD patient with a de novo Alu-mediated Xq24 rearrangement causing a deletion encompassing CUL4B, LAMP2, and also the other three neighboring genes. Typical to females heterozygous for CUL4B mutations, the patient was CS asymptomatic, however, presented with extremely skewed X-chromosome inactivation (XCI) ratios in peripheral white blood cells. As a result of the likely selection against CUL4B deficient clones, only minimal populations (~3%) of LAMP2 deficient leukocytes were identified by flow cytometry. On the contrary, myocardial LAMP2 protein expression suggested random XCI. We demonstrate that contiguous CUL4B and LAMP2 loss-of-function copy number variations occur and speculate that male patients carrying similar defects could present with features of both CS and DD.

• MeSH
• chromozomální delece MeSH
• dospělí MeSH
• elementy Alu genetika   MeSH
• exony genetika   MeSH
• glykogenóza typu IIb diagnóza   genetika   patofyziologie   MeSH
• inaktivace chromozomu X genetika   MeSH
• kardiomyopatie genetika   patofyziologie   MeSH
• kulinové proteiny genetika   MeSH
• lidé MeSH
• membránový protein 2 asociovaný s lyzozomy genetika   MeSH
• mentální retardace vázaná na chromozom X genetika   patofyziologie   MeSH
• mutace ztráty funkce genetika   MeSH
• myokard metabolismus   MeSH
• sodíko-draslíková ATPasa genetika   MeSH
• transkripční faktory genetika   MeSH
• variabilita počtu kopií segmentů DNA genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH

BACKGROUND: Niemann-Pick type C (NP-C) is a rare neurovisceral genetic disorder caused by mutations in the NPC1 or the NPC2 gene. NPC1 is a multipass-transmembrane protein essential for egress of cholesterol from late endosomes/lysosomes. To evaluate impacts of NPC1 mutations, we examined fibroblast cultures from 26 NP-C1 patients with clinical phenotypes ranging from infantile to adult neurologic onset forms. The cells were tested with multiple assays including NPC1 mRNA expression levels and allele expression ratios, assessment of NPC1 promoter haplotypes, NPC1 protein levels, cellular cholesterol staining, localization of the mutant NPC1 proteins to lysosomes, and cholesterol/cholesteryl ester ratios. These results were correlated with phenotypes of the individual patients. RESULTS: Overall we identified 5 variant promoter haplotypes. Three of them showed reporter activity decreased down to 70% of the control sequence. None of the haplotypes were consistently associated with more severe clinical presentation of NP-C. Levels of transcripts carrying null NPC1 alleles were profoundly lower than levels of the missense variants. Low levels of the mutant NPC1 protein were identified in most samples. The protein localised to lysosomes in cultures expressing medium to normal NPC1 levels. Fibroblasts from patients with severe infantile phenotypes had higher cholesterol levels and higher cholesterol/cholesteryl ester ratios. On the contrary, cell lines from patients with juvenile and adolescent/adult phenotypes showed values comparable to controls. CONCLUSION: No single assay fully correlated with the disease severity. However, low residual levels of NPC1 protein and high cholesterol/cholesteryl ester ratios associated with severe disease. The results suggest not only low NPC1 expression due to non-sense mediated decay or low mutant protein stability, but also dysfunction of the stable mutant NPC1 as contributors to the intracellular lipid transport defect.

• MeSH
• fibroblasty metabolismus   MeSH
• intracelulární signální peptidy a proteiny MeSH
• lidé MeSH
• membránové glykoproteiny * genetika   metabolismus   MeSH
• mladiství MeSH
• mutace genetika   MeSH
• transportní proteiny * genetika   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• Publikační typ
• abstrakt z konference MeSH

Danon disease (DD) is an X-linked disorder caused by mutations in the lysosomal-associated membrane protein 2 (LAMP2) gene (Xq24). DD is characterized by cognitive deficit, myopathy, and cardiomyopathy in male patients. The phenotype is variable and mitigated in females. The timely identification of de-novo LAMP2 mutated family members, many of whom are heterozygous females, remains critical for their treatment and family counseling. DD laboratory testing builds on minimally invasive quantification of the LAMP2 protein in white blood cells and characterization of the specific mutation. This integrative approach is particularly helpful when assessing suspect female heterozygotes. LAMP2 exon-copy number variations (eCNVs) were so far reported only in X-hemizygous male DD probands. In heterozygous female DD probands, the wild-type allele may hamper the identification of an eCNV even if it results in the complete abolition of LAMP2 transcription and/or translation. To document the likely underappreciated rate of occurrence and point out numerous potential pitfalls of detection of the LAMP2 eCNVs, we present the first two DD heterozygote female probands who harbor novel multi-exon LAMP2 deletions. Critical for counseling and recurrence prediction, we also highlight the need to search for somatic-germinal mosaicism in DD families.

• MeSH
• dítě MeSH
• dospělí MeSH
• exony genetika   MeSH
• glykogenóza typu IIb genetika   MeSH
• heterozygot MeSH
• lidé MeSH
• membránový protein 2 asociovaný s lyzozomy genetika   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• rodina MeSH
• rodokmen MeSH
• sekvence nukleotidů MeSH
• variabilita počtu kopií segmentů DNA genetika   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH

Ornithine transcarbamylase (OTC) deficiency is an X-linked disorder that causes recurrent and life-threatening episodes of hyperammonemia. The clinical picture in heterozygous females is highly diverse and derives from the genotype and the degree of inactivation of the mutated X chromosome in hepatocytes. Here, we describe molecular genetic, biochemical, and histopathological findings in the livers explanted from two female patients with late-onset OTC deficiency. Analysis of X-inactivation ratios by DNA methylation-based assays showed remarkable intra-organ variation ranging from 46:54 to 82:18 (average 70:30, n = 37), in favor of the active X chromosome carrying the mutation c.583G>C (p.G195R), in the first patient and from 75:25 to 90:10 (average 82:18, n = 20) in favor of the active X chromosome carrying the splicing mutation c.663+1G>A in the second patient. The X-inactivation ratios in liver samples correlated highly with the proportions of OTC-positive hepatocytes calculated from high-resolution image analyses of the immunohistochemically detected OTC in frozen sections that was performed on total area > 5 cm2. X-inactivation ratios in blood in both female patients corresponded to the lower limit of the liver values. Our data indicate that the proportion of about 20-30% of hepatocytes expressing the functional OTC protein is not sufficient to maintain metabolic stability. X-inactivation ratios assessed in liver biopsies taken from heterozygous females with X-linked disorders should not be considered representative of the whole liver.

• MeSH
• biopsie MeSH
• genotyp MeSH
• glutaminsynthetasa genetika   metabolismus   MeSH
• heterozygot MeSH
• inaktivace chromozomu X * MeSH
• játra enzymologie   MeSH
• lidé MeSH
• lidské chromozomy X genetika   MeSH
• nemoc z nedostatku ornithinkarbamoyltransferázy genetika   MeSH
• ornithinkarbamoyltransferasa genetika   metabolismus   MeSH
• pohlavní dimorfismus MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• abstrakt z konference MeSH

Mucopolysaccharidosis type II (MPS II) is an X-linked lysosomal storage disorder resulting from deficiency of iduronate-2-sulphatase activity. The disease manifests almost exclusively in males; only 16 symptomatic heterozygote girls have been reported so far. We describe the results of X-chromosome inactivation analysis in a 5-year-old girl with clinically severe disease and heterozygous mutation p.Arg468Gln in the IDS gene. X inactivation analysed at three X-chromosome loci showed extreme skewing (96/4 to 99/1) in two patient's cell types. This finding correlated with exclusive expression of the mutated allele. Induced pluripotent stem cells (iPSC) generated from the patient's peripheral blood demonstrated characteristic pluripotency markers, deficiency of enzyme activity, and mutation in the IDS gene. These cells were capable of differentiation into other cell types (cardiomyocytes, neurons). In MPS II iPSC clones, the X inactivation ratio remained highly skewed in culture conditions that led to partial X inactivation reset in Fabry disease iPSC clones. Our data, in accordance with the literature, suggest that extremely skewed X inactivation favouring the mutated allele is a crucial condition for manifestation of MPS II in females. This suggests that the X inactivation status and enzyme activity have a prognostic value and should be used to evaluate MPS II in females. For the first time, we show generation of iPSC from a symptomatic MPS II female patient that can serve as a cellular model for further research of the pathogenesis and treatment of this disease.

• MeSH
• iduronátsulfatasa genetika   metabolismus   MeSH
• inaktivace chromozomu X * MeSH
• indukované pluripotentní kmenové buňky * MeSH
• kultivované buňky MeSH
• lidé MeSH
• mukopolysacharidóza II diagnóza   enzymologie   genetika   MeSH
• mutace MeSH
• předškolní dítě MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH