br Funding This study was funded by a research

Funding This study was funded by a research grant from the French Ministry of Health (PHRC 2007, P071228) and sponsored by the Département de la Recherche Clinique et du Développement de l\'Assistance Publique–Hôpitaux de Paris. The Inserm unit 1134 and Institut National de la Transfusion Sanguine benefited from a Région Ile-de-France institutional funding (SESAME 2007 no. F-08-1104/R). The study was supported by grants from Laboratory of Excellence GR-Ex, reference ANR-11-LABX-0051. The labex GR-Ex is funded by the program “Investissements d\'avenir” of the French National Research Agency, reference ANR-11-IDEX-0005-02.
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Introduction Primary varicose vein disease constitutes one of the most frequent inherited disorders worldwide and entails a broad spectrum of cosmetic, psychological, medical, and socio-economic implications (Evans et al., 1994; Carpentier et al., 2004). Family based investigations suggested an autosomal dominant inheritance (Cornu-Thenard et al., 1994; Hach, 1967), but the origin of variant clinical courses and morphological presentations is still unknown. This has resulted in a long lasting and sometimes confusing debate on how to deal and treat best (Pannier and Rabe, 2012; Gloviczki and Gloviczki, 2012). Trunk and perforator types (Fig. 1a and b) of complicated and uncomplicated disease suggest different subsets of genetic origin. Thrombotic disease has been closely related to a common homozygous mutant genotype (TT) at c.677C>T, the most studied polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene (Milio et al., 2008; Wilmanns et al., 2011), coding for a key enzyme of one-carbon metabolism. The prevalence of c.677C>T accurately overlaps with geographic variations in the incidence of primary varicose veins (Wilmanns et al., 2011; Wilcken et al., 2003; Raffetto, 2011) and has been previously linked to the occurrence of varicose veins (Sverdlova et al., 1998). Primary varicose veins result from an asymmetric remodeling of extracellular matrix and smooth muscle ionomycin (Lim and Davies, 2009; Naoum and Hunter, 2007; Somers and Knaapen, 2006) contributing to wall thickening, valve incompetence and their typical corkscrew appearance. Pathognomonic tortuosities provide undistinguishable features of palpation and inspection and thus support genetic considerations. In this study, we report an association between the c.677C>T and the second most studied polymorphism of the MTHFR gene, c.1298A>C, both of which are linked to reduced enzyme activity, with morphological phenotypes and varying clinical presentations of primary varicose veins. The heterozygous or homozygous c.677C>T genotype was associated with the trunk phenotype and the heterozygous or homozygous c.1298A>C genotype with the perforator phenotype. We further linked the double heterozygous c.677C>T/c.1298A>C genotype (CTAC) with the combined trunk and perforator phenotype of primary varicose veins. In addition, we associated the homozygous mutant CC genotype at MTHFR c.1298A>C with the occurrence of congestive disease. Thus, we provide a clue to the impact of MTHFR polymorphisms c.677C>T and c.1298A>C as hereditary components of primary varicose vein disease.
Patients and Methods Clinical and duplex examination assessed tortuosities, reflux, venous dilation, thrombosis, swelling, pigmentation, eczema, scar and ulcer, inflammation, and painful, cord-like lesions to determine the morphological phenotype or the occurrence of complicated, progressive disease (Suppl. Table 1). Morphology was recorded as the trunk (Fig. 1a), perforator (Fig. 1b, Suppl. Table 2), or combined, indicating the origin of reflux from the deep venous system, or uncertain phenotypes. Incompetent perforators were recorded in upright sitting or standing position as dilated and draining into epifascial tributaries or segments of incompetent trunk veins. Clinical symptoms resulting from venous hypertension and mal-circulation were summarized as “congestive complication”, “congestive disease”, or C3–6 according to the revised CEAP (Clinical–Etiology–Anatomy–Pathophysiology) classification for chronic venous disorders (Suppl. Table 3) (Eklöf et al., 2004), and thus distinguished from asymptomatic presentation, CEAP C2. Patients were attributed to varicothrombosis in case of clinically apparent thrombotic lesions of varicose veins or to recurrent disease in case of new lesions subsequent to previous surgery in accordance with the REVAS definition (Perrin et al., 2000).