Genetic association of PROC variants with pulmonary embolism in Northern Chinese Han population

Evaluation of prothrombotic risk of two PROC hotspot mutations (Arg189Trp and Lys193del) in Chinese population: a retrospective study

BACKGROUND

R189W and K193del of protein C (PC) were hotspot mutations in Chinese population with venous thromboembolism (VTE), but almost two-thirds of patients with above mutations coexisting with other genetically or aquiredly prothrombotic risk factors. The aim of this study is to clarify the independent contributions of R189W or K193del to VTE risk.

METHODS

490 unrelated patients with a personal history of VTE and 410 healthy participants were enrolled in this study. Data of their demographics, family history, genetic and acquired thrombosis risk factors were collected and statistically analyzed.

RESULTS

PC R189W and K193del were identified in 3/410 (0.7%) and 7/410 (1.7%) healthy controls, and in 27/490 (5.5%) and 43/490 (8.8%) patients with VTE, respectively. Notably, about 70% of these mutant carriers combined with other genetic or acquired thrombophilic factors. After adjustment for age, gender, other inherited and acquired risk factors, we demonstrated that R189W and K193del were associated with 5.781-fold and 4.365-fold increased risk of VTE, respectively, which were significantly lower than the prothrombotic risk of anticoagulant deficiencies induced from rare mutations. Independent R189W or K193del mutation was not associated with earlier first-onset age as well as higher recurrent rate of VTE. However, combination of other genetic or acquired thrombophilic factors had supra-additive effects on those consequences. The more additional risk factors the patients had, the younger first-onset ages and higher risk of recurrence would be.

CONCLUSIONS

As the most frequent mutations for PC deficiency in Chinese population, both R189W and K193del mutations had limited independent contributions to VTE development compared with other rare mutations in PROC gene, but may act in concert with other genetic defects or acquired thrombotic risk factors to produce the final severe phenotype.

The evaluation of two genetic polymorphisms of paraoxonase 1 in patients with pulmonary embolism

BACKGROUND AND OBJECTIVE

Pulmonary embolism (PE) is caused by some genetic factors for more than half patients. Paraoxonase 1 (PON1) has significant anti-oxidative and anti-inflammatory effects. According to our knowledge, there is no study researching the relation between PON 1 gene polymorphisms and PE in the literature. Therefore, it is aimed to research possible impacts of PON 1 Q192R and L55M polymorphisms on PE, considering anti-inflammatory and anti-oxidative effects of PON 1 in Turkish population.

METHODS

One hundred and five PE patients and one hundred and seventeen controls were enrolled in this study. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses for the PON1 gene Q192R and L55M polymorphisms.

RESULTS

Any associations were not found between clinical and demographical characteristics of PE patients and the PON1 gene Q192R polymorphism; however, there were associations between surgery, chronic renal failure, and cerebrovascular disease on the history of patients and L55M polymorphism (P = .013, P = .037, and P = .031, respectively). Genotype and allele frequencies did not show any significant differences between patients and controls according to PON1 gene Q192R and L55M polymorphisms (P > .05).

CONCLUSION

The results of this study suggest that there is no correlation between PE and PON 1 gene Q192R and L55M polymorphisms in the Turkish population from the Central Black Sea region. Besides, whole genotypes and alleles of Q192R and L55M are not risk factors for patients with PE in this population.