Unveiling the untreated: development of a database algorithm to identify potential Fabry disease patients in Germany.

BACKGROUND: Fabry disease (FD), an X-linked lysosomal storage disorder, is caused by mutations in the gene encoding α-galactosidase A, resulting in lysosomal accumulation of globotriaosylceramide and other glycosphingolipids. Early detection of FD is challenging, accounting for delayed diagnosis and treatment initiation. This study aimed to develop an algorithm using a logistic regression model to facilitate early identification of patients based on ICD-10-GM coding using a German Sickness Fund Database. METHODS: The logistic regression model was fitted on a binary outcome variable based on either a treated FD cohort or a control cohort (without FD). Comorbidities specific to the involved organs were used as covariates to identify potential FD patients with ICD-10-GM E75.2 diagnosis but without any FD-specific medication. Specificity and sensitivity of the model were optimized to determine a likely threshold. The cut-point with the largest values for the Youden index and concordance probability method and the lowest value for closest to (0,1) was identified as 0.08 for each respective value. The sensitivity and specificity for this cut-point were 80.4% and 79.8%, respectively. Additionally, a sensitivity analysis of the potential FD patients with at least two codes of E75.2 diagnoses was performed. RESULTS: A total of 284 patients were identified in the potential FD cohort using the logistic regression model. Most potential FD patients were < 30 years old and female. The identification and incidence rates of FD in the potential FD cohort were markedly higher than those of the treated FD cohort. CONCLUSIONS: This model serves as a tool to identify potential FD patients using German insurance claims data.

Using Data from a Sickness Fund Claims Database to Assess the Treatment Patterns and Healthcare Resource Utilization among Patients with Metastatic Renal Cell Carcinoma in Germany.

OBJECTIVES: To characterize real-world prescribing patterns and their clinical and healthcare resource utilization (HRU) implications in patients with metastatic renal cell carcinoma (mRCC) treated in Germany. METHODS: Eligible individuals were enrolled in the "Bundesverband der Betriebskrankenkassen" claims database and received targeted mRCC therapy between 1 January 2008 and 31 December 2016. Prescribing patterns and HRU were characterized by treatment line and summarized by descriptive statistics. Proxy progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier curves. RESULTS: 536 patients receiving mRCC treatment were included. The median treatment duration was 4.2 months (interquartile range [IQR]: 1.7-9.3) for first-line therapy and 3.8 months (IQR: 1.7-9.1) for second-line therapy. Median PFS and OS estimates were similar for the first- and second-line treatments: PFS, 7.4 versus 7.2 months; OS, 14.9 versus 13.6 months. Mean HRU costs were higher for patients receiving first-line therapy (€7,253.2) compared with those receiving second-line therapy (€6,242.9). Exploratory stratification of outcomes by centre expertise suggested a possible trend towards improved OS in the 10 most experienced centres versus all -others: first-line, 18.4 versus 13.2 months; second-line, 16.4 versus 12.4 months. CONCLUSIONS: In routine care, German clinicians make rational prescribing decisions; possible variations in outcomes between centres warrant further investigation.

Design of a new fluorescent cofactor for DNA methyltransferases and sequence-specific labeling of DNA.

Sequence-specific labeling of DNA is of immense interest for analytical and functional studies of DNA. We present a novel approach for sequence-specific labeling of DNA using a newly designed fluorescent cofactor for the DNA methyltransferase from Thermus aquaticus (M.TaqI). Naturally, M.TaqI catalyzes the nucleophilic attack of the exocyclic amino group of adenine within the double-stranded 5'-TCGA-3' DNA sequence onto the methyl group of the cofactor S-adenosyl-L-methionine (AdoMet) leading to methyl group transfer. The design of a new fluorescent cofactor for covalent labeling of DNA was based on three criteria: (1) Replacement of the methionine side chain of the natural cofactor AdoMet by an aziridinyl residue leads to M.TaqI-catalyzed nucleophilic ring opening and coupling of the whole nucleoside to DNA. (2) The adenosyl moiety is the molecular anchor for cofactor binding. (3) Attachment of a fluorophore via a flexible linker to the 8-position of the adenosyl moiety does not block cofactor binding. According to these criteria the new fluorescent cofactor 8-amino[1''-(N''-dansyl)-4''-aminobutyl]-5'-(1-aziridinyl)-5'-deoxyadenosine (3) was synthesized. 3 binds about 4-fold better than the natural cofactor AdoMet to M.TaqI and is coupled with a short duplex oligodeoxynucleotide by M.TaqI. The identity of the expected modified nucleoside was verified by electrospray ionization mass spectrometry after enzymatic fragmentation of the product duplex. In addition, the new cofactor 3 was used to sequence-specifically label plasmid DNA in a M.TaqI-catalyzed reaction.

Rapid parallel mutation scanning of gene fragments using a microelectronic protein-DNA chip format.

We have developed a method for the de novo discovery of genetic variations, including single nucleotide polymorphisms and mutations, on microelectronic chip devices. The method combines the features of electronically controlled DNA hybridisation on open-format microarrays, with mutation detection by a fluorescence-labelled mismatch- binding protein. Electronic addressing of DNA strands to distinct test sites of the chip allows parallel analysis of several individuals, as demonstrated for mutations in different exons of the p53 gene. This microelectronic chip-based mutation discovery assay may substitute for time-consuming sequencing studies and will complement existing technologies in genomic research.

Coupling of a Nucleoside with DNA by a Methyltransferase.

How to outwit a methyltransferase: Methyltransferases (Mtases) catalyze the transfer of the activated methyl group from the cofactor S-adenosyl-L-methionine (1) to acceptors R within a large variety of biomolecules. Through the use of the cofactor analogue 2 a whole nucleoside was coupled to DNA in a Mtase-catalyzed reaction.