Publications by authors named "Christina T Lam"

Purpose: Sequencing-based genetic testing often identifies variants of uncertain significance (VUS) or fails to detect pathogenic variants altogether. We evaluated the utility of RNA sequencing (RNA-seq) to clarify VUS or identify missing variants in a clinical setting.

Methods: Over a 2-year period, genetics providers at a single institution referred 26 cases for clinical RNA-seq.

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Article Synopsis
  • - A rare genetic condition involving mitochondrial complex III deficiency and lactic acidosis, characterized by scalp alopecia, was identified in two unrelated cases and discussed further with a participant from the Undiagnosed Diseases Network (UDN).
  • - The participant had two autosomal recessive disorders discovered through genome sequencing: mitochondrial complex III deficiency and cataracts, with specifics on previously documented pathogenic variants for each condition.
  • - A combination of enzyme assays and cellular proteomics showed clear dysfunction in complex III and low levels of a crucial protein, validating the genetic mutations' pathogenic effects and broadening understanding of these rare disorders.
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Purpose: To summarise the clinical, molecular and biochemical phenotype of mannosyl-oligosaccharide glucosidase-related congenital disorders of glycosylation (MOGS-CDG), which presents with variable clinical manifestations, and to analyse which clinical biochemical assay consistently supports diagnosis in individuals with bi-allelic variants in .

Methods: Phenotypic characterisation was performed through an international and multicentre collaboration. Genetic testing was done by exome sequencing and targeted arrays.

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Purpose: Prolidase deficiency is a rare inborn error of metabolism causing ulcers and other skin disorders, splenomegaly, developmental delay, and recurrent infections. Most of the literature is constituted of isolated case reports. We aim to provide a quantitative description of the natural history of the condition by describing 19 affected individuals and reviewing the literature.

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Congenital disorders of glycosylation are a genetically and clinically heterogeneous group of >130 diseases caused by defects in various steps along glycan modification pathways. The vast majority of these monogenic diseases are autosomal recessive and have multi-systemic manifestations, mainly growth failure, developmental delay, facial dysmorphisms, and variable coagulation and endocrine abnormalities. Carbohydrate deficient transferrin (CDT) and protein-linked glycan analysis with mass spectrometry can diagnose some subtypes of congenital disorders of glycosylation (CDG), while many currently rely on massively parallel genomic sequencing for diagnosis.

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