RNAseq Supports the Molecular Genetic Diagnosis of Late-Onset ADA Deficiency
To the Editor:
Adenosine deaminase (ADA) deficiency is an autosomal recessive disorder of purine metabolism that typically presents as a severe combined immunodeficiency in infancy (OMIM: 102700). Approximately 10–15% of patients have a delayed clinical onset (6–24 months) and a smaller proportion present later still (4 years to adulthood) with a milder phenotype and gradual immunological deterioration .
Despite the expanding application of modern genetic techniques, the diagnosis of primary immunodeficiencies (PIDs) can be difficult due to the ever-increasing phenotypic heterogeneity of these disorders . Here, we report a case of late-onset ADA deficiency caused by two novel mutations. Both the clinical and genetic diagnoses were challenging and only achieved following the application of several molecular approaches. This case also illustrates the increasing importance of collaborative working between clinicians and laboratory diagnostic scientists.
A 7-year-old girl was...
This work is supported by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre and a Medical Research Council grant awarded to Professor Bonthron (MR/M009084/1).
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Disclosure of Potential Conflict of Interest
The authors declare that they have no conflicts of interest.
The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health.
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