Publication Date:
2018-11-29
Description:
Introduction: Venous thromboembolism (VTE), defined as deep venous thrombosis (DVT) and pulmonary embolism (PE), is a cause of significant morbidity and mortality worldwide, with an overall incidence of about 10,000,000 cases per year. The majority of VTEs are believed to be attributable to genetic factors. Yet, the five established heritable thrombophilias of factor V Leiden (FVL), prothrombin (PT) gene mutation, antithrombin (AT) deficiency, protein C (PC) deficiency, and protein S (PS) deficiency comprise only a small portion of VTEs, suggesting that further genetic factors contributing to VTE risk are unrecognized. In our previously published study, we performed whole exome sequencing (WES) in 64 patients with VTE and developed a 55-gene extended thrombophilia panel which identified 40 pathogenic or likely pathogenic variants or variants of uncertain significance (VUS) involving 22 different genes. Here, we present updated data from an expanded patient cohort. Methods: Blood was obtained from 101 patients with VTE. Genomic DNA was extracted and WES performed; mean coverage of the exome was 100x with 98% of the exome covered 〉/= 20 times. Variants were filtered for an allele frequency of 7% in the GnomAD database. A targeted analysis of the 55 genes in the extended thrombophilia panel was then performed. Variants in these genes were classified according to ACGM criteria as pathogenic, likely pathogenic, VUS, benign or likely benign. The number of patients with pathogenic or likely pathogenic variants and VUS in VTE patients was compared to a control population of 237 patients who had WES performed for reason other than VTE. The results of WES were also compared to those of traditional laboratory-based thrombophilia testing. Further, 17 VUS underwent in silico protein modeling to evaluate structural modifications. Results: Of the 101-patient study population, 46 were men and 55 women; 62% were Caucasian, 22% African American and 5% Hispanic; 15% had unprovoked VTE, 71% had provoked, 12% had both; and 55% had first degree family members with VTE. WES and extended thrombophilia testing identified a pathogenic or likely pathogenic variant or VUS in 69/101 (68%) VTE patients compared to 6/237 (2.5%) controls, a statistically significant difference (p-value
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
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