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Detecting mutations in the plasma of patients with solid tumors is becoming a valuable method of diagnosing and monitoring cancer. The TERTpromoter is mutated at high frequencies in multiple cancer types, most commonly at positions -124 and -146 (designated C228Tand C250T, respectively). Detection of these mutations has been challenging because of the high GC content of this region (approximately 80%). We describe development of novel probe-based droplet digital PCR assays that specifically detect and quantify these two mutations, along with the less common 242-243 CC>TTmutation, and demonstrate their application using human tumor and plasma samples from melanoma patients. Assay designs and running conditions were optimized using cancer cell line genomic DNAs with the C228Tor C250Tmutations. The limits of detection were 0.062% and 0.051% mutant allele fraction for the C228Tand C250Tassays, respectively. Concordance of 100% was observed between droplet digital PCR and sequencing-based orthogonal methods in the detection of TERTmutant DNA in 32 formalin-fixed, paraffin-embedded melanoma tumors. TERTmutantDNA was also identified in 21 of 27 plasma samples (78%) from patients with TERTmutanttumors, with plasma mutant allele fractions ranging from 0.06% to 15.3%. There were no false positives in plasma. These data demonstrate the potential of these assays to specifically detect and quantify TERTmutantDNA in tumors and plasma of cancer patients.

Insulin-degrading enzyme (IDE) is a 110 kDa chambered zinc metalloendopeptidase that degrades insulin, amyloid β, and other intermediate-sized aggregation prone peptides that adopt β-structures. Structural studies of IDE in complex with multiple physiological substrates have suggested a role for hydrophobic and aromatic residues of the IDE active site in substrate binding and catalysis. Here, we examine functional requirements for conserved hydrophobic and aromatic IDE active site residues that are positioned within 4.5 Å of IDE-bound insulin B chain and amyloid β peptides in the reported crystal structures for the respective enzyme–substrate complexes. Charge, size, hydrophobicity, aromaticity, and other functional group requirements for substrate binding IDE active site residues were examined through mutational analysis of the recombinant human enzyme and enzyme kinetic studies conducted using native and fluorogenic derivatives of human insulin and amyloid β peptides. A functional requirement for IDE active site residues F115, A140, F141, Y150, W199, F202, F820, and Y831 was established, and specific contributions of residue charge, size, and hydrophobicity to substrate binding, specificity, and proteolysis were demonstrated. IDE mutant alleles that exhibited enhanced or diminished proteolytic activity toward insulin or amyloid β peptides and derivative substrates were identified.

Nearly 80% of cancer patients do not have genetic mutation results available at initial oncology consultation; up to 25% of patients begin treatment before receiving their results. These factors hinder the ability to pursue optimal treatment strategies. This study validates a blood-based genome-testing service that provides accurate results within 72 hours. We focused on targetable variants in advanced non–small cell lung carcinoma—epidermal growth factor receptor gene (EGFR) variant L858R, exon 19 deletion (ΔE746−A750), and T790M; GTPase Kirsten ras gene (KRAS) variants G12C/D/V; and echinoderm microtubule associated protein like and 4 anaplastic lymphoma receptor tyrosine kinase fusion (EML4-ALK) transcripts 1/2/3. Test development included method and clinical validation using samples from donors with (n = 219) or without (n = 30) cancer. Clinical sensitivity and specificity for each variant ranged from 78.6% to 100% and 94.2% to 100%, respectively. We also report on 1643 non–small cell lung carcinoma samples processed in our CLIA-certified laboratory. Mutation results were available within 72 hours for 94% of the tests evaluated. We detected 10.5% mutations for EGFR sensitizing (n = 2801 samples tested), 13.8% mutations for EGFR resistance (n = 1055), 13.2% mutations in KRAS(n = 3477), and 2% mutations for EML4-ALKfusion (n = 304). This rapid, highly sensitive, and actionable blood-based assay service expands testing options and supports faster treatment decisions.

Despite significant research into media and political coverage of refugees and asylum seekers, and ongoing Commonwealth policies to resettle refugees to regional areas, analysis of the regional press is lacking. We reviewed articles from four regional newspapers using quantitative content analysis and qualitative content analysis to examine some initial trends in how regional newspapers represent refugees and asylum seekers. Despite the dominant negative framing of refugee issues at the national level, the regional media used positive, humanising frames and a broader range of sources in articles on local topics such as refugees’ personal stories. This reflects the community-building role of local journalism and challenges the familiar boundaries of the debate. However, there was a compelling distinction between articles on local and national topics, with the negative national discourse and dominance of government sources reflected in articles on national topics such as legislation and events.

To characterize the prevalence of and contributing factors to adult obesity in the most common recurrent copy-number variation (CNV), 22q11.2 deletion, given that other rare CNVs are known to have obesity phenotypes.

Purpose:To characterize the prevalence of and contributing factors to adult obesity in the most common recurrent copy-number variation (CNV), 22q11.2 deletion, given that other rare CNVs are known to have obesity phenotypes. Methods:In 207 adults with 22q11.2 deletion syndrome (22q11.2DS), we used available height and weight measurements to calculate body mass index (BMI) and recorded associated factors that could play a role in obesity. We used the maximum BMI per subject and logistic regression to test a model predicting obesity class. Results:The prevalence of obesity (BMI ≥30) in 22q11.2DS (n = 90, 43.5%; at median age of 26.7 years) was significantly greater than for Canadian norms (odds ratio (OR) 2.30, 95% confidence interval (CI) = 1.74–3.02, P < 0.0001), even after excluding individuals with a history of antipsychotic use. The regression model was significant (P < 0.0001). Psychotropic medication use and age, but not sex or presence of intellectual disability, were associated with higher obesity level. Ten (4.8%) individuals were diagnosed with type 2 diabetes at a median age of 39.5 years; the prevalence was higher in those with obesity (P < 0.01).Conclusion:The results suggest that adult obesity is related to the 22q11.2 deletion. The findings expand the potential genetic causes of obesity and have important implications for management of 22q11.2DS.Genet Med 19 2, 204–208.

The end of the 20th century saw the start of an HIV pandemic that brought death and suffering to millions. Anti-HIV drug therapy has improved the lives of many, although HIV-related respiratory complications remain extremely common worldwide

Targeted therapies in many cancers have allowed unprecedented progress in the treatment of disease. However, routine implementation of genomic testing is constrained due to: 1) limited amounts of sample (pg–ng range) per biological specimen, 2) diagnostic turnaround time and workflow, 3) cost, and 4) difficulties in detection of mutational loads below 5%. KRAS is mutated in approximately 40% of colorectal cancers (CRCs). The majority of mutations affect codons 12, 13, and 61 and indicate a negative response to anti–epidermal growth factor receptor (EGFR) therapy. To optimize therapy strategies for personalized care, it is critical to rapidly screen patient samples for the presence of multiple KRAS mutations.

Targeted therapies in many cancers have allowed unprecedented progress in the treatment of disease. However, routine implementation of genomic testing is constrained due to: 1) limited amounts of sample (pg–ng range) per biological specimen, 2) diagnostic turnaround time and workflow, 3) cost, and 4) difficulties in detection of mutational loads below 5%. KRAS is mutated in approximately 40% of colorectal cancers (CRCs). The majority of mutations affect codons 12, 13, and 61 and indicate a negative response to anti–epidermal growth factor receptor (EGFR) therapy. To optimize therapy strategies for personalized care, it is critical to rapidly screen patient samples for the presence of multiple KRAS mutations.