The impact of tumor NGS testing on hereditary cancer risk assessment and population management in an integrated community health care system

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Background: Next-generation sequencing (NGS) for tumor molecular profiling is used in Oncology to identify ‘actionable alterations’ for clinical trials or on/ off-label therapy. Tumor NGS can also reveal potentially heritable germline mutations. The frequency of such incidental germline mutations has been estimated to be 4-15%. The 2015 ASCO Statement supports communication of medically relevant incidental germline findings from somatic mutation profiling to patients (PTS). The impact of tumor NGS testing on hereditary cancer risk assessment programs in the context of a wider population management strategy is unknown. We sought to evaluate this within our Kaiser Permanente Northern California (KPNC) population with ready access to tumor NGS and an ongoing hereditary cancer risk assessment program. Methods: Kaiser Permanente Northern California (KPNC) is part of a large, integrated health care system. NGS at KPNC is performed in collaboration with STRATA Oncology, a precision oncology partnership. All NGS results are reviewed by a multidisciplinary KPNC Genomic Oncology Committee (GOC)which also includes genetic counselors and pathologists. We examined all NGS reports between November 2017 through December 2019 to determine the types of cancers tested, number with a possible germline mutation and number referred for genetic counseling and testing (GCT). Results: 4,825 PTS with advanced cancer underwent STRATA NGS testing. A total of 207 PTS (4.3%) were identified as potential germline mutation carriers, all 207 were recommended for GCT referral. Of these, 92 (45.0%) separately met 2020 NCCN Criteria for Genetic/Familial High-Risk Assessment (2020NG/FA), prior to tumor NGS; 115 (53.6%) did not and 3 (1.4%) had insufficient information. The cancers most frequently meeting NCCN criteria were pancreatic, breast and colon. Of the 92 PTS who met 2020NG/FA, 60 (65%) underwent GCT and 34 (57%) were confirmed to have a germline mutation. Of the 115 PTS that did not meet 2020NG/FA, 47 (41%) underwent GCT and 19 (40%) were confirmed to have a germline mutation. Overall germline mutations were confirmed in 16.5% of patients who did not meet 2020NG/FA and 37% who did. Conclusions: In our community-based integrated healthcare system, systematic review of next-generation sequencing results by an expert GOC led to more robust identification of germline mutation carriers and navigated them to appropriate GCT. Ongoing work will clarify data on cascade testing. We are currently developing automated workflows for GCT.

AXIN2 gene silencing reduces apoptosis through regulating mitochondria-associated apoptosis signaling pathway and enhances proliferation of ESCs by modulating Wnt/β-catenin signaling pathway

OBJECTIVE

Embryonic stem cells (ESCs) mainly originate from totipotent cells in early-stage of mammalian embryo and could proliferate in a manner of un-limitation. This study aimed to investigate roles of Axin2 in proliferation of ESCs and explore the associated mechanisms.

MATERIALS AND METHODS

Axis inhibition protein 2 (AXIN2) over-expression (LV5-AXIN2) and AXIN2 RNA interfere (LV3-AXIN2-RNAi) vectors were structured and transfected into H9 cells. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) was used to evaluate cell proliferative activity. Flow cytometry analysis was employed to measure apoptosis of H9 cells. AXIN2, β-catenin, transcription factor 4 (TCF4), c-myc, c-jun and Cyclin D mRNA levels and protein expressions were determined using quantitative real-time PCR (qRT-PCR) and Western blotting assay.

RESULTS

LV5-AXIN2 and LV3-AXIN2-RNAi were successfully structured with higher transfecting efficacy. AXIN2 gene silencing remarkably increased proliferative activity and AXIN2 treatment significantly induced apoptosis of H9 cells, comparing with blank vector group (p<0.05). AXIN2 gene silencing significantly enhanced B-cell lymphoma-2 (Bcl-2) expression and remarkably inhibited cleaved caspase-3 expression comparing to that in blank vector group (p<0.05). AXIN2-RNAi treatment significantly enhanced and AXIN2 over-expression significantly reduced β-catenin and TCF4 expression, comparing to that in blank vector group (p<0.05). AXIN2 gene silence activated down-stream molecules of Wnt/β-catenin signaling pathway, including c-jun, c-myc, and Cyclin D1 (p<0.05).

CONCLUSIONS

AXIN2 gene silencing reduced apoptosis by regulating mitochondria-associated apoptosis signaling pathway and enhanced proliferation by modulating molecules in Wnt/β-catenin signaling pathway. Therefore, targeting of aberrant apoptosis and AXIN2 might be a novel clinical strategy to inhibit aging and enhance self-renewal of ESCs.

Complete Regression of Rhabdomyosarcoma in an Adult Secondary to Postoperative Wound Infection Following Limb Salvage Surgery: A Case Report

CASE PRESENTATION

A 33-year old man presented with a 25-cm lower extremity embryonal rhabdomyosarcoma with presumed extensive nodal metastasis on positron emission topography scan. Neoadjuvant chemotherapy and radiation provided minimal response. Following limb salvage resection and flap coverage, a prolonged postoperative infection occurred requiring intravenous antibiotics and wound care over 5 months. Given the infection, no postoperative radiation or chemotherapy was administered. Eight months following surgery, positron emission topography scan showed complete regression of local and nodal disease. The patient has remained in complete remission for more than 4 years.

CONCLUSION

Postoperative wound infection leading to complete regression of embryonal rhabdomyosarcoma has not been reported. Stimulation of the innate and adaptive immune system through infectious elements is an area of ongoing immunotherapy research to improve sarcoma treatment outcomes.

Single-cell RNA sequencing reveals compartmental remodeling of tumor-infiltrating immune cells induced by anti-CD47 targeting in pancreatic cancer

Background

Human pancreatic ductal adenocarcinoma (PDAC) responds poorly to immune checkpoint inhibitor (ICPi). While the mechanism is not completely clear, it has been recognized that tumor microenvironment (TME) plays key roles. We investigated if targeting CD47 with a monoclonal antibody could enhance the response of PDAC to ICPi by altering the TME.

Methods

Using immunohistochemistry, we examined tumor-infiltrating CD68⁺ pan-macrophages (CD68⁺ M) and CD163⁺ M2 macrophages (CD163⁺ M2) and tumor expression of CD47 and PD-L1 proteins in 106 cases of PDAC. The efficacy of CD47 blockade was examined in xenograft models. CD45⁺ immune cells from syngeneic tumor models were subjected to single-cell RNA-sequencing (scRNA-seq) by using the 10x Genomics pipeline.

Results

We found that CD47 expression correlated with the level of CD68⁺ M but not CD163⁺ M2. High levels of tumor-infiltrating CD68⁺ M, CD163⁺ M2, and CD47 expression were significantly associated with worse survival. CD47^high/CD68⁺ M^high and CD47^high/CD163⁺ M2^high correlated significantly with shorter survival, whereas CD47^low/CD68⁺ M^low and CD47^low/CD163⁺ M2^low correlated with longer survival. Intriguingly, CD47 blockade decreased the tumor burden in the Panc02 but not in the MPC-83 syngeneic mouse model. Using scRNA-seq, we showed that anti-CD47 treatment significantly remodeled the intratumoral lymphocyte and macrophage compartments in Panc02 tumor-bearing mice by increasing the pro-inflammatory macrophages that exhibit anti-tumor function, while reducing the anti-inflammatory macrophages. Moreover, CD47 blockade not only increased the number of intratumoral CD8⁺ T cells, but also remodeled the T cell cluster toward a more activated one. Further, combination therapy targeting both CD47 and PD-L1 resulted in synergistic inhibition of PDAC growth in the MPC-83 but not in Panc02 model. MPC-83 but not Panc02 mice treated with both anti-CD47 and anti-PD-L1 showed increased number of PD-1⁺CD8⁺ T cells and enhanced expression of key immune activating genes.

Conclusion

Our data indicate that CD47 targeting induces compartmental remodeling of tumor-infiltrating immune cells of the TME in PDAC. Different PDAC mouse models exhibited differential response to the anti-CD47 and anti-PD-L1 blockade due to the differential effect of this combination treatment on the infiltrating immune cells and key immune activating genes in the TME established by the different PDAC cell lines.

P5753Jailed pressure wire to assess the side branch result for bifurcation lesions treated by provisional stenting strategy: iFR as a new index

Purpose

To analyze the feasibility and efficacy of the jailed pressure wire technique for bifurcation lesions treated by provisional stenting strategy and to assess the physiological side branch (SB) result using instantaneous wave free ratio (iFR).

Methods

Between June 2017 and December 2018, 50 patients who presented a bifurcation lesion considered appropriate for provisional stenting strategy were included in the study. Pressure wire was passed to side branch before treatment. Main vessel (MV) and side branch (SB) was predilated at the operator criteria. iFR determination was obtained in the SB baseline and after MV stenting (leaving the pressure wire jailed). Afterwards, the wire was removed to MV ostium to discard the possibility of drift. SB postdilation was performed if SB iFR was less than 0,89 (according to vessel thresholds established in clinical trials), evaluating the result by a new iFR determination.

Results

The mean age was 64±10 years. Sixteen patients (32%) had diabetes. Clinical presentation was stable angina in 26 patients (52%), non-STEMI in 19 patients (38%) and STEMI (non culprit lesion) in 5 patients (10%). The most frequent bifurcation type according to Medina classifications was 1,1,0 (21 patients, 42%). Seventeen patients (34%) had a true bifurcation lesion. The MV and SB reference diameter was 3,0±0,5 mm and 2,25±0,5 mm respectively. Most of the bifurcations were located at the left anterior descending artery/diagonal branch (27 bifurcations, 54%). Ten patients (20%) presented a distal left main bifurcation. Baseline SB iFR was 0,78±0,2. Under continuous SB iFR monitoring MV stenting was performed by trapping the pressure wire. After MV stenting, the SB iFR changed to 0,90±0,1. We confirmed the presence of drift in 5 patients (10%). In these cases, recalibration of the wire and SB rewiring was performed in 4 cases. In the remaining patient, rewiring was not possible even using specific coronary wires.

According to SB IFR, postdilation was necessary in 14 patients (28%). Final SB iFR was 0,94±0,03. A second stent was not necessary in any patient because final SB iFR was higher than 0.89 in all cases. We observed discordance between angiographic and physiological result in 17 cases (34%). All the wires could be removed. Forty wires (80%) were microscopically analyzed. Some grade of microscopic damage was found in 32 wires (80%), all of them distal to the pressure sensor. However, only one of these wires (2%) presented severe damage, and no case of fracture was observed.

After a mean follow up time of 10±6 months only one patient (2%) presented a major cardiac adverse event (acute coronary syndrome due to voluntary cessation of dual antiplatelet therapy).

Conclusions

The use of jailed pressure wire to monitor SB results for bifurcations treated by provisional stenting seems to be safe. The iFR index seems to provide new physiological information about the significance of the SB stenosis.

MiR-302 a/b/c suppresses tumor angiogenesis in hepatocellular carcinoma by targeting MACC1

OBJECTIVE

Hepatocellular carcinoma (HCC) is a hypervascularized tumor. Aberrant angiogenesis is the main cause, which results in cancer growth and progression. It has been showed that microRNA-302 cluster (miR-302) may be associated with angiogenesis. Here, we aimed to identify the role of miR-302a/b/c in the regulation of cell angiogenesis in HCC.

PATIENTS AND METHODS

MRNA expression of miR-302a/b/c and MACC1 was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The protein of MACC1 was measured using Western blot. Cells proliferation, migration, and invasion abilities were investigated via Cell Counting Kit-8 (CCK-8) assay or transwell assay, respectively. Tube formatting assays were used to explore the tube formation capacity. The interaction among miR-302a/b/c was analyzed by luciferase assay.

RESULTS

The expression of miR-302a/b/c was greatly reduced while MACC1 expression, whether mRNA or protein was conspicuously elevated in HCC tissues and cells. Then, functional experiment results showed miR-302a/b/c overexpression and MACC1 down-regulation inhibited the proliferation, migration, invasion ability, and tube formation capacity of HUVECs. In addition, we detected that miR-302a/b/c directly targeted MACC1 and suppressed MACC1 expression, and miR-302a/b/c could suppress tumor angiogenesis in HCC by targeting MACC1.

CONCLUSIONS

MiR-302a/b/c may function as a potential suppressor of tumor angiogenesis in HCC by targeting MACC1, indicating a promising target for HCC therapy.

Collection, particle sizing and detection of airborne viruses

Viruses that affect humans, animals and plants are often dispersed and transmitted through airborne routes of infection. Due to current technological deficiencies, accurate determination of the presence of airborne viruses is challenging. This shortcoming limits our ability to evaluate the actual threat arising from inhalation or other relevant contact with aerosolized viruses. To improve our understanding of the mechanisms of airborne transmission of viruses, air sampling technologies that can detect the presence of aerosolized viruses, effectively collect them and maintain their viability, and determine their distribution in aerosol particles, are needed. The latest developments in sampling and detection methodologies for airborne viruses, their limitations, factors that can affect their performance and current research needs, are discussed in this review. Much more work is needed on the establishment of standard air sampling methods and their performance requirements. Sampling devices that can collect a wide size range of virus-containing aerosols and maintain the viability of the collected viruses are needed. Ideally, the devices would be portable and technology-enabled for on-the-spot detection and rapid identification of the viruses. Broad understanding of the airborne transmission of viruses is of seminal importance for the establishment of better infection control strategies.

Normal human skin is superior to monkey oesophagus substrate for detection of circulating BP180-NC16A-specific IgG antibodies in bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease. Two antigens have been identified as targets of circulating autoantibodies (autoAbs) - BP180 and BP230 - with BP180 being a critical transmembrane adhesion protein of basal keratinocytes of the epidermis. The noncollagenous domain 16A (NC16A) of BP180 is the immunodominant epitope in patients with BP, and anti-BP180-NC16A IgG antibodies (Abs) correlate to disease activity. Routine serological testing and follow-up of BP relies on indirect immunofluorescence (IIF) of serum Abs, commonly performed on monkey oesophagus (ME), and/or enzyme-linked immunosorbent assay (ELISA) testing on recombinantly produced fragments of BP180 and BP230 (BP180-NC16A, BP230-C/N).

OBJECTIVES

To determine if NC16A epitopes are well represented on ME substrate.

METHODS

Sera from different BP cohorts were tested by IIF on ME and normal human skin (NHS). To confirm findings, affinity-purified anti-BP180-NC16A/BP230 polyclonal Abs and recombinant anti-BP180-NC16A/BP230 monoclonal antibodies (mAbs) were used.

RESULTS

For sensitive detection of BP180-NC16A-specific IgG Abs, sections of NHS are superior to the widely used ME. Confirmation comes from polyclonal affinity-purified anti-BP180-NC16A/BP230 Abs, and by mAbs cloned from a patient with active BP.

CONCLUSIONS

Use of NHS is preferable over ME in routine IIF testing for BP. These results are of clinical relevance because anti-BP180-NC16A IgG titres are correlated to disease activity and detecting them reliably is important for screening, diagnosis and follow-up of patients with BP.

Real-World Experiences with Pazopanib in Patients with Advanced Soft Tissue and Bone Sarcoma in Northern California

Background: Pazopanib was approved for advanced soft tissue sarcoma as a second- or third-line therapy based on the clinical trial "Pazopanib for metastatic soft-tissue sarcoma" (PALETTE). We hypothesized that the real-world experiences may be significantly different from the clinical trial results. Methods: We analyzed the response pattern of patients with advanced soft tissue and bone sarcoma who received pazopanib treatment between 1 January 2011 and 31 October 2018 in Kaiser Permanente Northern California. Results: A total of 123 patients with 23 different histologic subtypes were assessable. One patient with low-grade fibromyxoid sarcoma obtained complete response (CR) after 2 months of treatment with pazopanib, 12 patients (9.7%) obtained partial response (PR), 34 patients (27.6%) had stable disease (SD), while 76 patients (61.8%) developed progressive disease (PD). The disease control rate (DCR) was 46.3% (CR + PR + SD). Among the 12 patients with PR, 3 had undifferentiated pleomorphic sarcoma (UPS), 4 had leiomyosarcoma (LMS), 2 had pleomorphic rhabdomyosarcoma, 1 had pleomorphic liposarcoma, 1 had dedifferentiated liposarcoma, and 1 had angiosarcoma. The median duration of response was 9 months. Two patients with Ewing's sarcoma had SD for 6 and 13 months, and two patients with osteosarcoma had SD for 6 and 9 months. Among 65 patients assessed at 8 weeks, 9 had a response, and 10 had SD. Among 104 patients assessed at 12 weeks, 12 had a response, and 26 had SD. The median progression-free survival (PFS) was approximately 3 months for all 123 cases and for patients with UPS and LMS. Conclusions: Our cohort of patients with advanced soft tissue and bone sarcoma in Northern California treated with pazopanib had diverse histologic subtypes. The response rate (CR + PR) was higher than that of the PALETTE trial, while the DCR and the median PFS were significantly lower. The observation of PR in two patients with liposarcoma and durable SD in several patients with bone sarcoma indicates that pazopanib has activity in liposarcoma and bone sarcoma.

Synergistic inhibition of pancreatic cancer with anti-PD-L1 and c-Myc inhibitor JQ1

Human pancreatic ductal adenocarcinoma (PDAC) exhibits marginal responses to anti-PD-1/PD-L1 immunotherapy and its mechanism remains poorly understood. We have investigated the effect of anti-PD-L1 and c-Myc inhibition in PDAC. Using 87 patients with PDAC from our hospital database we found a significant correlation between the expression of PD-L1 and c-Myc. Moreover, the expression of both PD-L1 and c-Myc was associated with poor overall survival. In addition, we confirmed this finding with the PDAC patients in the TCGA database. Using several PDAC cell lines we demonstrated a significant correlation between the expression of PD-L1 and c-Myc. We also found that expression of PD-L1 correlated with high-grade histology. JQ1, an inhibitor of c-Myc inhibited PD-L1 expression and tumor growth. Using xenograft models, we demonstrated that the combination of JQ1 and anti-PD-L1 antibody exerted synergistic inhibition of PDAC growth. Our data demonstrated that the expression of PD-L1 and c-Myc may be helpful prognostic biomarkers, and their inhibition may potentially serve as an effective treatment for PDAC.

CRISPR/Cas9-mediated disruption of the immediate early-0 and 2 as a therapeutic approach to Bombyx mori nucleopolyhedrovirus in transgenic silkworm

The CRISPR/Cas9 system is a powerful tool for the treatment of infectious diseases. In our previous study, we knocked out the Bombyx mori nucleopolyhedrovirus (BmNPV) key genes and BmNPV-dependent host factor to generate transgenic antiviral strains. To further expand the range of target genes for BmNPV and more effectively prevent and control pathogenic infections, we performed gene editing and antiviral analysis by constructing a target-directed baculovirus early transcriptional activator immediate early-0 (ie-0) and 2 (ie-2) transgenic silkworm line. We hybridized it with Cas9 transgenic line to produce a double-positive transgenic Cas9(+)/sgIE0-sgIE2(+) line that could activate the CRISPR gene editing system. We first demonstrated that the system is capable of efficiently editing target genes and resulting in fragment deletions in the BmNPV genome. Survival rate of the transgenic Cas9(+)/sgIE0-sgIE2(+) line reached 65% after inoculation with 1 × 10⁶ occlusion bodies/larva. Molecular analysis showed that BmNPV DNA replication and viral gene expression level in the transgenic Cas9(+)/sgIE0-sgIE2(+) line were significantly inhibited compared with the control Cas9(-)/sgIE0-sgIE2(-) line. These results indicated that IE-0 and IE-2, as baculovirus early transcriptional activators, can be used as target sites for gene therapy and that multigene editing could expand the range of target sites for research to create silkworm resistance breeds.

Mechanisms of Primary and Secondary Resistance to Immune Checkpoint Inhibitors in Cancer

Immune checkpoint inhibitors (ICPis) have revolutionized cancer therapy with broad activities against a wide range of malignancies. However, in many malignancies their efficacy remains limited due to the primary resistance. Furthermore, a high percentage of patients develop progression due to the secondary resistance even after obtaining a response or achieving a stable disease. In this review, we will discuss the mechanisms that underlie the primary and secondary resistance to ICPis in cancer immunotherapy and provide an overview to impart a broad understanding of the critical issues that are encountered in clinical oncology practice.

Analysis of Genetic Polymorphism and Genetic Distance of 19 Autosomal STR Loci in Jiangsu Han Population

OBJECTIVES

To investigate the distribution of alleles in 19 autosomal short tandem repeat （STR） loci in Jiangsu Han population.

METHODS

Goldeneye^® 20A kit was used to detect 9 025 samples. Genetic analysis was performed on typing data of 19 autosomal STR loci, and genetic distance with other 17 populations was analyzed.

RESULTS

All the 19 autosomal STR loci were consistent with the Hardy-Weinberg equilibrium （P>0.05）, with the heterozygosity 0.616 1-0.916 3, probability of match 0.012 8-0.202 6, discrimination power 0.797 4-0.987 2, probability of paternity exclusion 0.310 8-0.828 8, and polymorphic information content 0.561 7-0.913 6. The cumulative discrimination power and cumulative probability of exclusion were 0.999 999 999 999 999 998 434 1 and 0.999 999 989, respectively. The Jiangsu Han population had close genetic distances with the Han population in Tianjin, Hunan and Jilin, and significant difference with Han population in Aletai region in Xinjiang （P<0.05）.

CONCLUSIONS

The STR allele polymorphism data and population genetic parameters of Jiangsu Han population can provide data support for the forensic application of these STR loci in Jiangsu Han population.

Association of Inflammatory Markers with Disease Progression in Patients with Metastatic Melanoma Treated with Immune Checkpoint Inhibitors

INTRODUCTION

We investigated the effect of inflammatory biomarkers (neutrophil, platelet, and lymphocyte counts) on risk of progression in patients with metastatic melanoma treated with an immune checkpoint inhibitor targeting programmed cell death protein-1 (PD-1).

METHODS

This retrospective cohort study included 108 patients with malignant melanoma treated with an anti-PD-1 checkpoint inhibitor from August 2014 through December 2015. The outcome was disease progression noted on imaging or clinical examination. Follow-up began on the date of initiation of anti-PD-1 therapy and ended on the date of progression, disenrollment, death of causes other than malignant melanoma, or the end of the study in February 2017.

RESULTS

The median time from initiating therapy with an anti-PD-1 checkpoint inhibitor (nivolumab or pembrolizumab) to the end of follow-up was 118 days. After adjustment, baseline neutrophil and platelet counts were associated with progression. The hazard ratio (HR) for neutrophil counts ≥ 5501/μL vs ≤ 3900/μL was 2.3 (95% confidence interval [CI] = 1.2-4.6, p < 0.05). For platelet counts ≥ 304,000 vs ≤ 215,000/μL, the HR was 2.0 (CI = 1.0-3.9, p < 0.05). For lymphocyte counts ≥ 1716/μL vs ≤ 1120/μL, the HR was 0.5 (CI = 0.2-1.0, p = 0.05).

CONCLUSION

For patients with metastatic melanoma treated with nivolumab or pembrolizumab, higher neutrophil or platelet counts, or lower lymphocyte counts, are associated with higher risk of progression. For these patients, we recommend more frequent assessment for progression and closer follow-up, especially for patients with substantial comorbidities or poor physical performance.

Whole exome sequencing as a diagnostic adjunct to clinical testing in fetuses with structural abnormalities

OBJECTIVES

To evaluate the diagnostic yield of prenatal whole exome sequencing (WES) for monogenic disorders in fetuses with structural malformations and normal results on cytogenetic testing, and to describe information on pathogenic variants that is provided by WES.

METHODS

Karyotyping, chromosomal microarray analysis (CMA) and WES were performed sequentially on stored samples from a cohort of 3949 pregnancies with fetal structural abnormalities detected on ultrasound and/or magnetic resonance imaging, referred between January 2011 and December 2015. Diagnostic rates of the three techniques were investigated overall, for phenotypic subgroups and for proband-only vs fetus-mother-father samples. Information on pathogenic variants was identified by WES.

RESULTS

Overall, 18.2% (720/3949) of fetuses had an abnormal karyotype. Pathogenic copy number variants were detected on CMA in 8.2% (138/1680) of fetuses that had a normal karyotype result. WES performed on a subgroup of 196 fetuses with normal CMA and karyotype results revealed the putative genetic variants responsible for the abnormal phenotypes in 47 cases (24%). The molecular diagnosis rates for fetus-mother-father and proband-only samples were 26.5% (13/49) and 23.1% (34/147), respectively. Variants of uncertain significance were detected in 12.8% (25/196) of fetuses, of which 22 were identified in the fetal proband-only group (15%; 22/147) and three in the fetus-mother-father group (6.1%; 3/49). The incidental finding rate was 6.1% (12/196).

CONCLUSIONS

WES is a promising method for the identification of genetic variants that cause structural abnormalities in fetuses with normal results on karyotyping and CMA. This enhanced diagnostic yield has the potential to improve the clinical management of pregnancies and to inform better the reproductive decisions of affected families. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

[Genetic Polymorphism of 30 InDel Loci in Han Population from Jiangsu Province]

OBJECTIVES

To investigate the genetic information of 30 insertion/deletion （InDel） loci in Han population from Jiangsu Province, and to explore the application values of Investigator® DIPplex kit for guiding the forensic analysis in Han population from Jiangsu Province.

METHODS

The autosomal InDel loci of 305 unrelated healthy Han individuals from Jiangsu Province were genotyped and analysed by Investigator® DIPplex kit, and the allelic frequencies and forensic parameters of 30 InDel loci were statistically analysed.

RESULTS

The distribution of 30 InDel loci in Han population from Jiangsu Province conformed to Hardy-Weinberg equilibrium. The minor allele frequencies of 21 InDel loci were above 0.3. The polymorphism information content ranged from 0.089 to 0.375, while the discrimination power distributed from 0.093 to 0.500. The paternity exclusion in duo cases and trio cases were 0.047-0.250 and 0.046-0.219, respectively. The linkage disequilibrium analysis of 30 InDel loci showed that all loci were independent from each other. The combined discrimination power was 1-7.369×10⁻⁸, whereas the combined mean exclusion chance in duo cases was 0.998 933 978, in trio cases was 0.997 806 392. The F_st values were all less than 0.06 except HLD118 and other four loci, which showed small differences between groups.

CONCLUSIONS

The InDel loci of Investigator® DIPplex kit can be used as complementary genetic markers for the cases associated with forensic genetics.