scholarly journals Next‐generation sequencing identifies rare pathogenic and novel candidate variants in a cohort of Chinese patients with syndromic or nonsyndromic hearing loss

2020 ◽  
Vol 8 (12) ◽  
Author(s):  
Yan‐Bao Xiang ◽  
Chen‐Yang Xu ◽  
Yun‐Zhi Xu ◽  
Huan‐Zheng Li ◽  
Li‐Li Zhou ◽  
...  
2020 ◽  
Vol 5 (3) ◽  
pp. 467-479 ◽  
Author(s):  
Malinda Butz ◽  
Amber McDonald ◽  
Patrick A Lundquist ◽  
Melanie Meyer ◽  
Sean Harrington ◽  
...  

Abstract Background Deafness and hearing loss are common conditions that can be seen independently or as part of a syndrome and are often mediated by genetic causes. We sought to develop and validate a hereditary hearing loss panel (HHLP) to detect single nucleotide variants (SNVs), insertions and deletions (indels), and copy number variants (CNVs) in 166 genes related to nonsyndromic and syndromic hearing loss. Methods We developed a custom-capture next-generation sequencing (NGS) reagent to detect all coding regions, ±10 flanking bp, for the 166 genes related to nonsyndromic and syndromic hearing loss. Our validation consisted of testing 52 samples to establish accuracy, reproducibility, and analytical sensitivity. In addition to NGS, supplementary methods, including multiplex ligation-dependent probe amplification, long-range PCR, and Sanger sequencing, were used to ensure coverage of regions that had high complexity or homology. Results We observed 100% positive and negative percentage agreement for detection of SNVs (n = 362), small indels (1–22 bp, n = 25), and CNVs (gains, n = 8; losses, n = 17). Finally, we showed that this assay was able to detect variants with a variant allele frequency ≥20% for SNVs and indels and ≥30% to 35% for CNVs. Conclusions We validated an HHLP that detects SNVs, indels, and CNVs in 166 genes related to syndromic and nonsyndromic hearing loss. The results of this assay can be utilized to confirm a diagnosis of hearing loss and related syndromic disorders associated with known causal genes.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e20506-e20506
Author(s):  
Lin Li ◽  
Naiquan Mao ◽  
Yingcheng Lyu ◽  
Huayue Lin ◽  
Kefeng Wang ◽  
...  

e20506 Background: Differentiation of multiple primary lung cancer (MPLC) from intrapulmonary metastasis (IPM) is critical to determine clinical stage. Although clinicopathological features could provide certain evidences, it’s still challenging to identify the tumor malignancy accurately. In General, standard histopathologic approach is adequate in most cases, but has notable limitations in the recognition of IPMs. Herein, we propose an integrated molecular algorithm to facilitate MPLCs and IPMs diagnosis in the clinical practice. Methods: 40 Chinese patients with lung adenocarcinomas were enrolled in the study, 84 tumor samples were collected for next-generation sequencing. Somatic alterations with variant allele fraction (VAF) ≥1% were taken into account for molecular algorithm. A genomic database of 2,471 Chinese lung adenocarcinomas (LUAD) was used to calculate odds of coincidental occurrence, prevalence of individual mutation prevalence. Tumor relatedness diagnosed by histopathologic assessment was contrasted with comparative genomic profiling by subsequent NGS. Moreover, the performance of molecular algorithm prediction was evaluated as well. Results: Firstly, we compared the performance of comprehensive next-generation sequencing (NGS) with standard histopathologic approaches for distinguishing NSCLC subtypes in clinical practice. The genomic profiling was described as following: EGFR alterations occurred more frequently in MPLCs compared to IPMs (77.1% vs 50.0%, P<0.05). Further analysis showed that TP53 alterations occurred less frequently in MPLCs compared to large Chinese cohort (22.9% vs 51.0%, P<0.05). TP53 alterations occurred less frequently in MPLCs compared to large Chinese cohort (P<0.05). The classifications based on the three different methodologies mentioned above were compared. Molecular algorithm prediction was concordant with NGS in 21 cases (52.5%), particularly in the prediction of MPLC. Retrospective review highlighted several histologic challenges, including morphologic progression in some IPMs. For the five undetermined cases, two showed differences in architectural patterns, and remained cases have nodules presented as adenocarcinoma in situ, or minimally invasive adenocarcinoma. Of 28 MPLC cases defined by NGS, 25 cases had unique somatic mutations per pair Based on calculation from the prevalence of EGFR L858R mutation (27%) in large Chinese cohort, the odds of coincidental occurrence of the mutation in two unrelated tumors was 7.3%. Taking together, EGFR alterations occurred more frequently in MPLCs compared to IPMs (77.1% vs 50.0%, P<0.05). Molecular algorithm prediction was concordant with NGS in 21 cases (52.5%). Conclusions: Our results support broad panel NGS to assist differential diagnosis to assist approach in clinical practice. It is necessary to conduct large clinical study to establish comprehensive algorithm models to assist diagnosis and predict clinical outcome.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Lijuan Zhang ◽  
YuYe Shi ◽  
Yue Chen ◽  
Shandong Tao ◽  
Wenting Shi ◽  
...  

Abstract Background Clonal hematopoiesis (CH) can be found in various myeloid neoplasms (MN), such as myelodysplastic syndromes (MDS), myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN), also in pre-MDS conditions. Methods Cytogenetics is an independent prognostic factor in MDS, and fluorescence in-situ hybridization (FISH) can be used as an adjunct to karyotype analysis. In the past 5 years, only 35 of 100 newly diagnosed MDS and MDS/MPN patients were identified abnormalities, who underwent the FISH panel. In addition, we examined a cohort of 51 cytopenic patients suspected MDS or MDS/MPN with a 20-gene next generation sequencing (NGS), including 35 newly diagnosed MN patients and 16 clonal cytopenias of undetermined significance (CCUS) patients. Results Compared with the CCUS group, the MN group had higher male ratio (22/13 vs 10/6), cytogenetics abnormalities rate (41.4% vs 21.4%) and frequency of a series of mutations, such as ASXL1 (28.6% vs 25%), U2AF1 (25.7% vs 25%), RUNX1 (20% vs 0.0%); also, higher adverse mutations proportion (75% vs 85.2%), and double or multiple mutations (54.3% vs 43.75%). There were 7 MN patients and 4 CCUS patients who experienced cardio-cerebrovascular embolism events demonstrated a significant difference between the two groups (25% vs 20%). Ten of the 11 patients had somatic mutations, half had DNA methylation, while the other half had RNA splicing. Additionally, six patients had disease transformation, and four patients had mutated U2AF1, including two CCUS cases and two MDS-EB cases. Following up to January 2021, there was no significant difference in over survival between the CCUS and MN groups. Conclusion NGS facilitates the diagnosis of unexplained cytopenias. The monitoring and management of CCUS is necessary, also cardio-cerebrovascular embolism events in patients with CH need attention in the clinical practice.


2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Liang Xia ◽  
Yangjia Cao ◽  
Yang Guo ◽  
Guangyi Ba ◽  
Qiong Luo ◽  
...  

Mutations in the COL4A3 gene are frequently reported to be associated with various types of hereditary nephropathy. COL4A3 encodes the α3 chain of type IV collagen, which is the main structural protein in the basement membrane. Mutations in this gene are always related to kidney performance, and deafness and ocular lesion have also been reported. In this study, using next-generation sequencing, we investigated the DNA of a family visiting a clinic for hearing loss. A new missense mutation was found in COL4A3 of 5 patients, c.3227C>T (p.P1076L). Based on these results, we predict that the mutation is pathogenic and leads to abnormal collagen IV. Here, we report for the first time on this autosomal dominant syndrome, characterized by hearing loss and eye abnormalities, but without renal damage, in all carriers. Since the oldest patient in the trial was less than 50 years old, however, we recommend that renal examination be reviewed regularly. Our results reveal expansion in the mutation spectrum of the COL4A3 gene and phenotypic spectrum of collagen IV disease. Our study suggests that next-generation sequencing is an economical and effective method and may help in the accurate diagnosis and treatment of these patients.


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