Investigation on genetic thrombophilic factors in FFPE autopsy tissue from subjects who died from pulmonary embolism

Abstract

Venous thromboembolism (VTE) is a multifactorial disease determined by a combination of inherited and acquired factors. Inherited factors include mutations in the genes coding for coagulation factors, some of which seem to exert a differential influence on the risk of developing deep vein thrombosis (DVT) and pulmonary embolism (PE). In post-mortem studies of subjects who have died from pulmonary embolism (PE), the analysis of the factors that may have augmented the VTE risk is often limited to acquired factors. This is due to the complexity-and sometimes the unfeasibility-of analyzing genetic factors and to insufficient knowledge of their individual roles in PE development. The present study used formalin-fixed paraffin-embedded (FFPE) tissue to investigate a panel of 12 polymorphisms-the largest ever studied-that affect the VTE risk. Tissue samples came from post-mortem examinations performed by the specialists of the Section of Legal Medicine of the Department of Pathology of Marche's Polytechnic University, and by the specialists of Health Care District Hospital of Imola, on 44 subjects who died from PE in the period 1997-2014. All individuals were found to have at least one mutation affecting the VTE risk. The present study demonstrates that genetic analysis can be performed post-mortem and the results are useful for forensic investigations, especially from MTHFR C677T and PAI-1 4G/5G polymorphisms. Broader studies using the techniques described herein are needed to determine the relative influence of the individual polymorphisms and their interaction in PE deaths.

Genetic association study of fatal pulmonary embolism

“…Mantel-Haenszel pooled OR after a fixed-effect meta-analysis was conducted for the combined data set of Brandimarti et al [21] and our study results using the metan command in STAT12.0 with an increment of 0.1 to account for zero fields. As the meta-analysis comprised nine different variants, the level of statistical significance was adjusted accordingly (α = 0.006).…”

“…Brandimarti et al conducted a study in an Italian population investigating associations between 12 thrombophilic risk factors and VTE in 44 individuals who died from PE. Strong associations between PE and the polymorphisms C677T (MTHFR), Pai-1 4G/5G and ITGB3 were found [21].…”

“…A total of 27 candidate gene variants were selected based on previous literature. Twelve SNPs used in the study conducted by Brandimarti et al [21] were chosen in order to examine whether their results can be replicated in our larger sample. The National Center for Biotechnology Information (NCBI) PubMed database was searched for papers assessing other relevant VTE and PE associated SNPs or SNPs affecting the coagulation of blood and their prevalence in the general population as well as in VTE-exposed populations.…”

“…SNPs displaying poor clustering in the wet lab testing were excluded from further analyses. Altogether 22 SNPs, including nine of those SNPs tested by Brandimarti et al [21], could be successfully genotyped. Table 1 displays the SNPs used in this study.…”

“…These findings emphasize the necessity of considering DVT and PE as different phenotypes in VTE genetic studies. Only one study investigating a broad panel of genetic VTE risk factors in patients with fatal PE has been reported so far [21]. Brandimarti et al conducted a study in an Italian population investigating associations between 12 thrombophilic risk factors and VTE in 44 individuals who died from PE.…”