# Protective Effect of Factor XIII Intron-K G Allele on Subclinical Vascular Disease

## TL;DR

This study shows that a specific genetic variant in Factor XIII protects against early signs of vascular disease, regardless of obesity or diabetes.

## Contribution

The protective effect of the FXIII Intron-K G allele on subclinical vascular disease is identified independently of other risk factors.

## Key findings

- The Intron-K G allele significantly reduces carotid intima-media thickness (cIMT) progression.
- This protective effect remains after adjusting for age, sex, and other vascular risk factors.
- Obesity and T2DM do not influence the protective role of the Intron-K G allele.

## Abstract

Carotid artery intima–media thickness (cIMT), a pre-clinical vascular change that accompanies atherosclerosis is considered as a cardiovascular risk factor. Coagulation factor XIII (FXIII) stabilizes the fibrin clot and increases its resistance to fibrinolysis. Regarding FXIII Val34Leu polymorphism, the protective effect of the Leu34 allele in the presence of elevated fibrinogen levels against myocardial infarction was demonstrated. Our aim was to investigate the effect of FXIII polymorphisms on cIMT. Patients with obesity (n = 69), type 2 diabetes mellitus (T2DM) (n = 104), and age- and sex-matched healthy controls (n = 82) were enrolled. FXIII polymorphisms (Val34Leu, His95Arg, Intron-K C>G) were determined by RT-PCR with FRET detection and melting curve analysis. cIMT was determined by B-mode ultrasound. Differences in cIMT between control (median: 0.5965, IQR: 0.5115–0.6580 mm) and T2DM (median: 0.7105, IQR: 0.5948–0.7568 mm), as well as between obese (median: 0.6105, IQR: 0.5455–0.6780 mm) and diabetic groups, were found (p < 0.0001 and p = 0.003, respectively). Genotype and allele frequencies of the studied polymorphisms did not differ between subgroups. In the study group (n = 255) after adjustment for age and sex, the presence of Intron-K G allele showed a significant and independent protective effect against cIMT progression in a separate model (p = 0.005) and after adjusting for other parameters associated with cIMT (p = 0.015). FXIII Intron-K G allele provides a protective effect against subclinical vascular disease in the studied population, and this effect is independent of the presence of obesity, as well as T2DM, Leu34 allele, and fibrinogen levels.