Publications by authors named "R G M Timmermans"

Deep-intronic (DI) variants represent approximately 10%-12% of disease-causing genetic defects in -associated Stargardt disease (STGD1). Although many of these DI variants are amenable to antisense oligonucleotide-based splicing-modulation therapy, no treatment is currently available. These molecules are mostly variant specific, limiting their applicability to a broader patient population.

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Article Synopsis
  • Clinical exome sequencing (ES) aids in diagnosing rare genetic disorders by analyzing protein-coding sequences, but 40-60% of patients still lack a conclusive diagnosis, with some revealing monoallelic variants in recessive disorders.* -
  • The study explored short-read genome sequencing (GS) on 174 individuals with identified monoallelic variants, successfully uncovering additional pathogenic variants in five patients and rare non-coding variants in 24 others, with three variants confirmed to affect splicing.* -
  • Overall, GS increased the diagnostic yield, identifying a likely second pathogenic variant in 4.6% of the cohort and providing a possible diagnosis for 12.1%, suggesting it could be a valuable first-tier
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Background: Current guidelines indicate that patients with extreme oligozoospermia or azoospermia should be tested for chromosomal imbalances, azoospermia factor (AZF) deletions and/or CFTR variants. For other sperm abnormalities, no genetic diagnostics are recommended.

Objectives: To determine whether exome sequencing (ES) with combined copy number variant (CNV) and single nucleotide variant (SNV) analysis is a reliable first-tier method to replace current methods (validation study), and to evaluate the diagnostic yield after 10 months of implementation (evaluation study).

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Background: Maternal cell contamination (MCC) in prenatal samples poses a risk for misdiagnosis, and therefore, testing for contamination is necessary during genetic analysis of prenatal specimens. MCC testing is currently performed as a method separate from the diagnostic method. With the increasing application of whole exome sequencing (WES) in prenatal diagnosis, we sought to develop a method to estimate the level of contamination from WES data, aiming to eliminate the need for a separate MCC test.

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Hypophosphatasia (HPP) is a rare disorder, resulting from loss-of-function variants of the ALPL gene encoding non-tissue specific alkaline phosphatase (TNSALP). Presentation varies largely, with increased severity usually occurring with earlier disease onset. Here we describe the clinical improvement of a 57-year-old woman with childhood onset HPP, after initiating treatment with asfotase alfa (Strensiq®).

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