| 1. |
- McCreary, D., et al.
(författare)
-
Development and Validation of a Targeted Next-Generation Sequencing Gene Panel for Children With Neuroinflammation
- 2019
-
Ingår i: Jama Network Open. - : American Medical Association (AMA). - 2574-3805. ; 2:10
-
Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE Neuroinflammatory disorders are a range of severe neurological disorders causing brain and spinal inflammation and are now increasingly recognized in the pediatric population. They are often characterized by marked genotypic and phenotypic heterogeneity, complicating diagnostic work in clinical practice and molecular diagnosis. OBJECTIVE To develop and evaluate a next-generation sequencing panel targeting genes causing neuroinflammation or mimicking neuroinflammation. DESIGN, SETTING, AND PARTICIPANTS Cohort study in which a total of 257 genes associated with monogenic neuroinflammation and/or cerebral vasculopathy, including monogenic noninflammatory diseases mimicking these entities, were selected. A customized enrichment capture array, the neuroinflammation gene panel (NIP), was created. Targeted high-coverage sequencing was applied to DNA samples taken from eligible patients referred to Great Ormond Street Hospital in London, United Kingdom, between January 1, 2017, and January 30, 2019, because of onset of disease early in life, family history, and/or complex neuroinflammatory phenotypes. MAIN OUTCOMES AND MEASURES The main outcome was the percentage of individuals with definitive molecular diagnoses, variant classification, and clinical phenotyping of patients with pathogenic variants identified using the NIP panel. The NIP panel was initially validated in 16 patients with known genetic diagnoses. RESULTS The NIP was both sensitive (95%) and specific (100%) for detection of known mutations, including gene deletions, copy number variants, small insertions and deletions, and somatic mosaicism with allele fraction as low as 3%. Prospective testing of 60 patients (30 [50%] male; median [range] age, 9.8 [0.8-20] years) presenting with heterogeneous neuroinflammatory phenotypes revealed at least 1 class 5 (clearly pathogenic) variant in 9 of 60 patients (15%); 18 of 60 patients (30%) had at least 1 class 4 (likely pathogenic) variant. Overall, a definitive molecular diagnosis was established in 12 of 60 patients (20%). CONCLUSIONS AND RELEVANCE The NIP was associated with molecular diagnosis in this cohort and complemented routine laboratory and radiological workup of patients with neuroinflammation. Unexpected genotype-phenotype associations in patients with pathogenic variants deviating from the classic phenotype were identified. Obtaining an accurate molecular diagnosis in a timely fashion informed patient management, including successful targeted treatment in some instances and early institution of hematopoietic stem cell transplantation in others.
|
|
| 2. |
- Nanthapisal, S., et al.
(författare)
-
Deficiency of Adenosine Deaminase Type 2 A Description of Phenotype and Genotype in Fifteen Cases
- 2016
-
Ingår i: Arthritis & Rheumatology. - : Wiley. - 2326-5191. ; 68:9, s. 2314-2322
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. To describe the clinical features, genotype, and treatment in a series of subjects with confirmed adenosine deaminase 2 (ADA2) deficiency. Methods. All symptomatic subjects were referred for genetic testing for suspected ADA2 deficiency; relatives of index cases were also screened. Demographic, clinical, and laboratory characteristics and treatments were recorded. Genetic analyses included whole-exome sequencing in 4 subjects and Sanger sequencing of CECR1 (the gene for cat eye syndrome chromosome region candidate 1) in all subjects. Assays for ADA2 enzyme activity and quantitative polymerase chain reaction analysis of CECR1 messenger RNA (mRNA) were also performed. Results. We identified 15 subjects with ADA2 deficiency, 5 of whom were asymptomatic (relatives of index cases; ages 5-42 years). Homozygous or compound heterozygous mutations in CECR1 were identified in all subjects. Phenotypic manifestations in the patients with symptomatic ADA2 deficiency included livedo racemosa (73.3%), neurologic involvement (53.3%), and immunodeficiency (46.7%). CECR1 mRNA expression in 8 subjects, including 5 who were presymptomatic, was significantly lower than in healthy controls (P=0.0016). Subjects with ADA2 deficiency (with or without symptoms) also had lower ADA2 enzyme activity compared to healthy pediatric controls (P<0.0001) and patients with sporadic (nonfamilial) childhood polyarteritis nodosa (PAN) without CECR1 mutation (P= 0.0108). Anti-tumor necrosis factor therapy was required in 9 of the 10 symptomatic subjects. Conclusion. The clinical manifestations of ADA2 deficiency ranged in severity from limited cutaneous involvement to severe multisystemic vasculitis; one-third of our cases (5 of 15) were currently asymptomatic, and required close monitoring. We recommend CECR1 screening for unaffected siblings of index cases, cases of familial vasculitis, and cases of PAN that is resistant to standard treatment.
|
|
