Germline and Mutations in High-Risk Chinese Breast and/or Ovarian Cancer Patients and Families.

Background: RAD51C and RAD51D are crucial in homologous recombination (HR) DNA repair. The prevalence of the RAD51C and RAD51D mutations in breast cancer varies across ethnic groups. Associations of RAD51C and RAD51D germline pathogenic variants (GPVs) with breast and ovarian cancer predisposition have been recently reported and are of interest.

Application of droplet digital PCR in minimal residual disease monitoring of rare fusion transcripts and mutations in haematological malignancies.

Leukaemia of various subtypes are driven by distinct chromosomal rearrangement or genetic abnormalities. The leukaemogenic fusion transcripts or genetic mutations serve as molecular markers for minimal residual disease (MRD) monitoring. The current study evaluated the applicability of several droplet digital PCR assays for the detection of these targets at RNA and DNA levels (atypical BCR::ABL1 e19a2, e23a2ins52, e13a2ins74, rare types of CBFB::MYH11 (G and I), PCM1::JAK2, KMT2A::ELL2, PICALM::MLLT10 fusion transcripts and CEBPA frame-shift and insertion/duplication mutations) with high sensitivity.

INSurVeyor: improving insertion calling from short read sequencing data.

Insertions are one of the major types of structural variations and are defined as the addition of 50 nucleotides or more into a DNA sequence. Several methods exist to detect insertions from next-generation sequencing short read data, but they generally have low sensitivity. Our contribution is two-fold.

HFE promotes mitotic cell division through recruitment of cytokinetic abscission machinery in hepatocellular carcinoma.

HFE (Hemochromatosis) is a conventional iron level regulator and its loss of function due to gene mutations increases the risk of cancers including hepatocellular carcinoma (HCC). Likewise, studies focusing on HFE overexpression in cancers are all limited to linking up these events as a consequence of iron level deregulation. No study has explored any iron unrelated role of HFE in cancers.

How does re-classification of variants of unknown significance (VUS) impact the management of patients at risk for hereditary breast cancer?

Background: The popularity of multigene testing increases the probability of identifying variants of uncertain significance (VUS). While accurate variant interpretation enables clinicians to be better informed of the genetic risk of their patients, currently, there is a lack of consensus management guidelines for clinicians on VUS.

Methods: Among the BRCA1 and BRCA2 mutations screening in 3,544 subjects, 236 unique variants (BRCA1: 86; BRCA2: 150) identified in 459 patients were being reviewed.

Germline mutations in Chinese ovarian cancer with or without breast cancer.

Background: Ovarian and breast cancers are known to have significant genetic components. Considering the differences in the mutation spectrum across ethnicity, it is important to identify hereditary breast and ovarian cancer (HBOC) genes mutation in Chinese for clinical management.

Methods: Two cohorts of 451 patients with ovarian cancer only (OV) and 93 patients with both breast and ovarian (BROV) cancers were initially screened for BRCA1, BRCA2, TP53, and PTEN.

Germline Mutation in High-Risk Chinese Breast and/or Ovarian Cancer Patients.

The prevalence of the mutation in breast cancer varies across different ethnic groups; hence, it is of intense interest to evaluate the cancer risk and clinical association of the mutation in Chinese breast and/or ovarian cancer patients. We performed sequencing with a 6-gene test panel (, , , and ) to identify the prevalence of the germline mutation among 2631 patients with breast and/or ovarian cancer. In this cohort, 39 mutations were identified with 24 types of mutation variants, where the majority of the mutations were frame-shift mutations and resulted in early termination.

A Case Report of Germline Compound Heterozygous Mutations in the Gene of an Ovarian and Breast Cancer Patient.

The germline carrier of the pathogenic mutation has been well proven to confer an increased risk of breast and ovarian cancer. Despite biallelic pathogenic mutations being extremely rare, they have been reported to be embryonically lethal or to cause Fanconi anemia (FA). Here we describe a patient who was a 48-year-old female identified with biallelic pathogenic mutations of the gene, with no or very subtle FA-features.

Evaluation on the use of Nanopore sequencing for direct characterization of coronaviruses from respiratory specimens, and a study on emerging missense mutations in partial RdRP gene of SARS-CoV-2.

Coronavirus disease 2019 (COVID-19) pandemic has been a catastrophic burden to global healthcare systems. The fast spread of the etiologic agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlights the need to identify unknown coronaviruses rapidly for prompt clinical and public health decision making. Moreover, owing to the high mutation rate of RNA viruses, periodic surveillance on emerging variants of key virus components is essential for evaluating the efficacy of antiviral drugs, diagnostic assays and vaccines.

Mutation screening of germline TP53 mutations in high-risk Chinese breast cancer patients.

Background: Germline TP53 mutations are associated with Li-Fraumeni syndrome, a severe and rare hereditary cancer syndrome. Despite the rarity of germline TP53 mutations, the clinical implication for mutation carriers and their families is significant. The risk management of TP53 germline mutation carriers is more stringent than BRCA carriers, and radiotherapy should be avoided when possible.

Rapid and economical drug resistance profiling with Nanopore MinION for clinical specimens with low bacillary burden of Mycobacterium tuberculosis.

Objective: We designed and tested a Nanopore sequencing panel for direct tuberculosis drug resistance profiling. The panel targeted 10 resistance-associated loci. We assessed the feasibility of amplifying and sequencing these loci from 23 clinical specimens with low bacillary burden.

Genome Sequences of SARS-CoV-2 Strains Detected in Hong Kong.

We sequenced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes from deep throat saliva samples of three imported cases in Hong Kong by Nanopore sequencing. Epidemiological and clinical features of these coronavirus disease 2019 (COVID-19) cases were presented for genomic epidemiology studies.

An economical Nanopore sequencing assay for human papillomavirus (HPV) genotyping.

Background: Human papillomavirus (HPV) testing has been employed by several European countries to augment cytology-based cervical screening programs. A number of research groups have demonstrated potential utility of next-generation sequencing (NGS) for HPV genotyping, with comparable performance and broader detection spectrum than current gold standards. Nevertheless, most of these NGS platforms may not be the best choice for medium sample throughput and laboratories with less resources and space.

Potential utility of targeted Nanopore sequencing for improving etiologic diagnosis of bacterial and fungal respiratory infection.

Background: Diversified etiology of lower respiratory tract infection renders diagnosis challenging. The mainstay microbial culture is time-consuming and constrained by variable growth requirements. In this study, we explored the use of Nanopore sequencing as a supplementary tool to alleviate this diagnostic bottleneck.

Germline Mutation in 1338 BRCA-Negative Chinese Hereditary Breast and/or Ovarian Cancer Patients: Clinical Testing with a Multigene Test Panel.

Differences in the mutation spectrum across ethnicities suggest the importance of identifying genes in addition to common high penetrant genes to estimate the associated breast cancer risk in China. A total of 1338 high-risk breast cancer patients who tested negative for germline BRCA1, BRCA2, TP53, and PTEN mutations between 2007 and 2017 were selected from the Hong Kong Hereditary Breast Cancer Family Registry. Patient samples were subjected to next-generation DNA sequencing using a multigene panel (Color Genomics).

Rapid detection of chromosomal translocation and precise breakpoint characterization in acute myeloid leukemia by nanopore long-read sequencing.

Detection of chromosomal translocation is a key component in diagnosis and management of acute myeloid leukemia (AML). Targeted RNA next-generation sequencing (NGS) is emerging as a powerful and clinically practical tool, but it depends on expression of RNA transcript from the underlying DNA translocation. Here, we show the clinical utility of nanopore long-read sequencing in rapidly detecting DNA translocation with exact breakpoints.

Distinct mutation spectrum, clinical outcome and therapeutic responses of typical complex/monosomy karyotype acute myeloid leukemia carrying TP53 mutations.

The present study aimed to define a subtype of complex/monosomal karyotype (CK/MK) acute myeloid leukemia (AML) by its distinct clinical features, p53 signaling and responses to p53 targeting agents. Ninety-eight young adults (range: 21-60 years; median: 49 years) with CK/MK AML were studied. They received standard induction, consolidation and allogeneic hematopoietic stem cell transplantation from siblings or matched unrelated donors if available.

Next-generation sequencing and molecular cytogenetic characterization of ETV6-LYN fusion due to chromosomes 1, 8 and 12 rearrangement in acute myeloid leukemia.

In a newly diagnosed patient with acute myeloid leukemia (AML) and complex cytogenetics and negative for gene mutations associated with myeloid neoplasms, RNA sequencing by next-generation sequencing (NGS) through a large cancer-related gene panel showed ETV6-LYN leukemic fusion transcript. Breakpoint analysis of the NGS reads showed fusion of exon 5 of the ETV6 gene to exon 8 of the LYN gene. Metaphase fluorescence in situ hybridization (FISH) inferred a four-break rearrangement of three chromosomes, namely 1, 8 and 12.

BAMClipper: removing primers from alignments to minimize false-negative mutations in amplicon next-generation sequencing.

Amplicon-based next-generation sequencing (NGS) has been widely adopted for genetic variation detection in human and other organisms. Conventional data analysis paradigm includes primer trimming before read mapping. Here we introduce BAMClipper that removes primer sequences after mapping original sequencing reads by soft-clipping SAM/BAM alignments.

INDELseek: detection of complex insertions and deletions from next-generation sequencing data.

Background: Complex insertions and deletions (indels) from next-generation sequencing (NGS) data were prone to escape detection by currently available variant callers as shown by large-scale human genomics studies. Somatic and germline complex indels in key disease driver genes could be missed in NGS-based genomics studies.

Results: INDELseek is an open-source complex indel caller designed for NGS data of random fragments and PCR amplicons.

Detection of Germline Mutation in Hereditary Breast and/or Ovarian Cancers by Next-Generation Sequencing on a Four-Gene Panel.

Mutation in BRCA1/BRCA2 genes accounts for 20% of familial breast cancers, 5% to 10% of which may be due to other less penetrant genes which are still incompletely studied. Herein, a four-gene panel was used to examine the prevalence of BRCA1, BRCA2, TP53, and PTEN in hereditary breast and ovarian cancers in Southern Chinese population. In this cohort, 948 high-risk breast and/or ovarian patients were recruited for genetic screening by next-generation sequencing (NGS).

Germline RECQL mutations in high risk Chinese breast cancer patients.

Recently, RECQL was reported as a new breast cancer susceptibility gene. RECQL belongs to the RECQ DNA helicase family which unwinds double strand DNA and involved in the DNA replication stress response, telomere maintenance and DNA repair. RECQL deficient mice cells are prone to spontaneous chromosomal instability and aneuploidy, suggesting a tumor-suppressive role of RECQL in cancer.

Clinical evaluation of panel testing by next-generation sequencing (NGS) for gene mutations in myeloid neoplasms.

Background: Genomic techniques in recent years have allowed the identification of many mutated genes important in the pathogenesis of acute myeloid leukemia (AML). Together with cytogenetic aberrations, these gene mutations are powerful prognostic markers in AML and can be used to guide patient management, for example selection of optimal post-remission therapy. The mutated genes also hold promise as therapeutic targets themselves.