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Raynaud's syndrome is a dysautonomia where exposure to cold causes vasoconstriction and hypoxia, particularly in the extremities. We performed meta-analysis in four cohorts and discovered eight loci (ADRA2A, IRX1, NOS3, ACVR2A, TMEM51, PCDH10-DT, HLA, and RAB6C) where ADRA2A, ACVR2A, NOS3, TMEM51, and IRX1 co-localized with expression quantitative trait loci (eQTLs), particularly in distal arteries. CRISPR gene editing further showed that ADRA2A and NOS3 loci modified gene expression and in situ RNAscope clarified the specificity of ADRA2A in small vessels and IRX1 around small capillaries in the skin. A functional contraction assay in the cold showed lower contraction in ADRA2A-deficient and higher contraction in ADRA2A-overexpressing smooth muscle cells. Overall, our study highlights the power of genome-wide association testing with functional follow-up as a method to understand complex diseases. The results indicate temperature-dependent adrenergic signaling through ADRA2A, effects at the microvasculature by IRX1, endothelial signaling by NOS3, and immune mechanisms by the HLA locus in Raynaud's syndrome., Competing Interests: Declaration of interests J.M.E. is an inventor on patents and patent applications related to CRISPR screening technologies, has received materials from 10× Genomics unrelated to this study, and has received speaking honoraria from GSK plc., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: To compare the microRNAs (miRNAs) contained within serum exosomes isolated from patients with Raynaud's phenomenon (RP) and negative antinuclear antibodies (ANA) to the miRNA contained in serum exosomes isolated from patients with RP and positive ANA., Methods: Serum exosomes were isolated employing a polymer precipitation procedure. Next Generation Sequencing (NGS) was used to identify the miRNAs contained in the exosomes isolated from the two clinical cohorts and to analyse the differences in their contents., Results: The NGS results identified six miRNAs that displayed significant differences in their content between serum exosomes from patients with RP with negative serum ANA compared to miRNAs contained in serum exosomes from patients with ANA-positive RP., Conclusions: A comparative analysis of miRNAs contained within serum exosomes of patients with RP and negative ANA vs. samples from patients with RP and positive ANA identified several differentially expressed miRNAs that may represent non-invasive biomarkers to assist in the identification of patients with RP at risk of evolving into systemic sclerosis.

Raynaud's phenomenon (RP) is a common vasospastic disorder that causes severe pain and ulcers, but despite its high reported heritability, no causal genes have been robustly identified. We conducted a genome-wide association study including 5,147 RP cases and 439,294 controls, based on diagnoses from electronic health records, and identified three unreported genomic regions associated with the risk of RP (p < 5 × 10 -8 ). We prioritized ADRA2A (rs7090046, odds ratio (OR) per allele: 1.26; 95%-CI: 1.20-1.31; p < 9.6 × 10 -27 ) and IRX1 (rs12653958, OR: 1.17; 95%-CI: 1.12-1.22, p < 4.8 × 10 -13 ) as candidate causal genes through integration of gene expression in disease relevant tissues. We further identified a likely causal detrimental effect of low fasting glucose levels on RP risk (r G  = -0.21; p-value = 2.3 × 10 -3 ), and systematically highlighted drug repurposing opportunities, like the antidepressant mirtazapine. Our results provide the first robust evidence for a strong genetic contribution to RP and highlight a so far underrated role of α 2A -adrenoreceptor signalling, encoded at ADRA2A, as a possible mechanism for hypersensitivity to catecholamine-induced vasospasms., (© 2023. Springer Nature Limited.)

Background: Raynaud's phenomenon (RP) describes the phenomenon of recurrent vasospasm of digital arteries, associated with skin colour changes: pallor, cyanosis and erythema. Twin studies have indicated a genetic predisposition for RP; however, the precise aetiology of RP remains unknown. It is thought that genetic variation in temperature-responsive or vasospastic genes might underlie RP so performed a candidate gene study in a large, population based sample. We assessed the association between RP and single nucleotide polymorphisms (SNPs) in the TRPA1, TRPM8, CALCA, CALCB and NOS1 genes., Methods: Analysis included a total of 4276 individuals from the TwinsUK database. RP status had been determined using validated, self-administered questionnaires and was diagnosed in 640 individuals (17.6%). 66 tag SNPs across the candidate genes were tested for association with RP status using a linear regression model, accounting for covariates. Adjustment was made for multiple testing. RegulomeDB and GTEx databases were used to assess possible functional effects of the polymorphisms., Results: Nominally significant associations between RP and four SNPs in NOS1 and one in CALCB were identified. After permutation testing, rs527590 SNP in NOS1 passed the significance threshold. RegulomeDB scores indicated an unlikely functional effect of this variant, while the survey of the GTEx database found the SNP and several variants in linkage disequilibrium to be cis-eQTLs in skin., Conclusion: Results indicate that RP is associated with variation in gene NOS1. This finding may be related to the observation that the significant SNP in NOS1 is known to exhibit functional influence on the gene expression.

The HANAC syndrome is caused by mutations in the gene coding for collagen4a1, a major component of blood vessel basement membranes. Ocular symptoms include an increase in blood vessel tortuosity and occasional hemorrhages. To examine how vascular defects can affect neuronal function, we analyzed the retinal phenotype of a HANAC mouse model. Heterozygous mutant mice displayed both a thinning of the basement membrane in retinal blood vessels and in Bruch's membrane resulting in vascular leakage. Homozygous mice had additional vascular changes, including greater vessel coverage and tortuosity. This greater tortuosity was associated to higher expression levels of vascular endothelial growth factor (VEGF). These major changes to the blood vessels were correlated with photoreceptor dysfunction and degeneration. The neuronal damage was associated with reactive gliosis in astrocytes and Müller glial cells, and by the migration of microglial cells into the outer retina. This study illustrates how vascular changes can trigger neuronal degeneration in a new model of HANAC syndrome that can be used to further study dysfunctions of neurovascular coupling., Summary Statement: This study provides a phenotypic analysis of a novel mouse model of HANAC syndrome focusing on the retinal aspect. It recapitulates most of the aspects of the human disease and is therefore a great tool to study and to address this condition., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Collagen IV is a major component of basement membranes (BMs). The α1(IV) chain, encoded by the COL4A1 gene, is expressed ubiquitously and associates with the α2(IV) chain to form the α1α1α2(IV) heterotrimer. Several COL4A1 mutations affecting a conformational domain containing integrin-binding sites are responsible for the systemic syndrome of hereditary angiopathy, nephropathy, aneurysms, and cramps (HANAC). To analyze the pathophysiology of HANAC, Col4a1 mutant mice bearing the p.Gly498Val mutation were generated. Analysis of the skeletal muscles of Col4a1 G498V mutant animals showed morphologic characteristics of a muscular dystrophy phenotype with myofiber atrophy, centronucleation, focal inflammatory infiltrates, and fibrosis. Abnormal ultrastructural aspects of muscle BMs was associated with reduced extracellular secretion of the mutant α1α1α2(IV) trimer. In addition to muscular dystrophic features, endothelial cell defects of the muscle capillaries were observed, with intracytoplasmic accumulation of the mutant α1α1α2(IV) molecules, endoplasmic reticulum cisternae dilation, and up-regulation of endoplasmic reticulum stress markers. Induction of the unfolded protein response in Col4a1 mutant muscle tissue resulted in an excess of apoptosis in endothelial cells. HANAC mutant animals also presented with a muscular functional impairment and increased serum creatine kinase levels reflecting altered muscle fiber sarcolemma. This extensive description of the muscular phenotype of the Col4a1 HANAC murine model suggests a potential contribution of primary endothelial cell defects, together with muscle BM alterations, to the development of COL4A1-related myopathy., (Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Objective: To explore whether polymorphic variants of the HTR1B gene are associated with the susceptibility of Raynauds' Phenomenon (RP) coursed by vibration., Methods: 148 subjects exposed to vibration for more than 2 years were classified into either induced white finger (VWF) group (n = 72), or non-VWF group (n = 76). Vibration exposure levels were measured and assessed following ISO 5349-1:2001 protocol. All workers were genotyped by sequencing for the single nucleotide polymorphisms (SNPs) in the 5'-flanking and coding region of HTR1B. Genetic characteristics and linkage disequilibrium (LD) were analyzed with Haploview. Serum serotonin levels of each subject were detected using ELISA. The association between the susceptibility of vascular damage and genotype was analyzed via logistic regression., Results: 7 known SNPs were obtained and their allele frequencies were inserted into the Hardy-Weinberg equilibrium. rs6297 variant genotype had an increased risk of VWF compared with wild genotype (OR = 2.14, 95% CI = 1.04- 4.58, P < 0.05). rs6298 mutant type (AG+GG) was found to have a significant interaction on vibration exposure LN(CEI), accounting for VWF occurrence. LN(5-HT) level is significantly different between the VWF group (x¯±s= 1.99±1.09 ng/mL) and the non-VWF group (x¯±s= 2.72±1.47 ng/mL)., Conclusions: Serotonin levels may affect the progression of secondary RP. Polymorphic variants of the HTR1B gene are associated with the susceptibility of secondary RP in vibration-exposed occupational populations of Chinese Han people.

Hereditary angiopathy, nephropathy, aneurysms, and muscle cramps (HANAC) syndrome is an autosomal dominant syndrome caused by mutations in COL4A1 that encodes the α1 chain of collagen IV, a major component of basement membranes. Patients present with cerebral small vessel disease, retinal tortuosity, muscle cramps, and kidney disease consisting of multiple renal cysts, chronic kidney failure, and sometimes hematuria. Mutations producing HANAC syndrome localize within the integrin binding site containing CB3[IV] fragment of the COL4A1 protein. To investigate the pathophysiology of HANAC syndrome, we generated mice harboring the Col4a1 p.Gly498Val mutation identified in a family with the syndrome. Col4a1 G498V mutation resulted in delayed glomerulogenesis and podocyte differentiation without reduction of nephron number, causing albuminuria and hematuria in newborns. The glomerular defects resolved within the first month, but glomerular cysts developed in 3-month-old mutant mice. Abnormal structure of Bowman's capsule was associated with metalloproteinase induction and activation of the glomerular parietal epithelial cells that abnormally expressed CD44,α-SMA, ILK, and DDR1. Inflammatory infiltrates were observed around glomeruli and arterioles. Homozygous Col4a1 G498V mutant mice additionally showed dysmorphic papillae and urinary concentration defects. These results reveal a developmental role for the α1α1α2 collagen IV molecule in the embryonic glomerular basement membrane, affecting podocyte differentiation. The observed association between molecular alteration of the collagenous network in Bowman's capsule of the mature kidney and activation of parietal epithelial cells, matrix remodeling, and inflammation may account for glomerular cyst development and CKD in patients with COL4A1-related disorders., (Copyright © 2016 by the American Society of Nephrology.)

We describe a case of H syndrome with massive skin involvement, retroperitoneal fibrosis and Raynaud's phenomenon. A 48-year-old man with parents of a consanguineous marriage, first appeared with decreased urine output, skin sclerosis on his inner thighs and short stature (142 cm, 47 kg). The patient had suffered from hearing loss since the age of 1 year, and his secondary sexual characteristics had not developed. Computed tomography showed periaortic fibrosis, bilateral ureteral stenosis, hydronephrosis and sclerosis of the germinal cords. A biopsy from the retroperitoneal mass revealed remarkable fibrosis with chronic inflammatory cells. Biopsies from the skin lesion showed thick collagen bundles through the dermis and lymphohistiocytic infiltration with numerous plasma cells. Serum inflammatory markers, such as C-reactive protein, vascular endothelial factor, transforming growth factor-β and soluble interleukin-2 receptor, were elevated. Prednisolone was effective in treating skin lesions and in lowering serum inflammatory markers. After a long period of follow up, genomic DNA of the patient was obtained, and we identified a homozygous mutation in exon 5, c.625G>A, which caused transition of glycine to arginine, p.Gly208Arg, in the patient, but not in DNA samples from another 50 healthy individuals. This is the first case of H syndrome with Raynaud's phenomenon and retroperitoneal fibrosis, and the first Japanese case of H syndrome reported in the English published work with a novel mutation in the SLC29A3 gene., (© 2015 Japanese Dermatological Association.)

COL4A1-associated disorders encompass a wide range of hereditary vasculopathy, including porencephaly and HANAC (adult-onset hemorrhagic stroke with cerebral aneurysm and retinal arterial tortuosity, renal cysts, and thenar muscle cramp). It remains elusive whether or not porencephaly and HANAC are molecularly distinctive disorders due to different classes of mutations. We report on a girl with porencephaly and an episode of microangiopathic hemolysis in infancy and her father with HANAC, both of whom had a heterozygous missense mutation of COL4A1 (c.3715G>A, p.G1239R). The current observation implies phenotypic diversities of COL4A1 mutations., (© 2014 Wiley Periodicals, Inc.)

We have investigated the prevalence and possible association of inherited prothrombotic risk factors in patients with primary Raynaud's phenomenon (PRP) and migraine. We performed genotypic analysis of FVLeiden, prothrombin G20210A, methyltetrahydrofolate reductase C677T and FXIII-A V34L mutations in these patients. Two hundred patients with primary Raynaud's phenomenon of Hungarian origin with migraine (57 female, one male, mean age of 43.8 ± 11.5 years) or without migraine (101 female, 41 male, mean age of 41.8 ± 14.5 years) were included in this study. Duration of PRP among migrainous patients was significantly longer than patients without migraine. The prevalence of methyltetrahydrofolate reductase T677 allele among patients with migraine was significantly higher than in patients without migraine (odds ratio 2.1, 95% CI: 1.4-3.3, p = 0.001). The prevalence of other thrombosis-associated alleles did not differ between patients with or without migraine. FVLeiden mutation, prothrombin G20210A mutation, and FXIII-A V34L polymorphism have no apparent effect on the occurrence of migraine in PRP.

Background: Primary biliary cirrhosis (PBC) is a disease with genetic and environmental pathogenetic background. Chemicals, infectious agents, hormone therapy, reproductive history and surgical interventions have been implicated in the induction of PBC. Familial PBC has been documented in first degree relatives (FDR). Most cohort studies are genetically heterogeneous. Our study aimed to determine eventual lifestyle or disease associations and familial occurrence rates in a genetically homogeneous and geographically defined population of PBC patients., Methods: 111 consenting PBC patients, were compared with 115 FDR and 149 controls matched for age, sex, Cretan origin and residence. All participants completed a questionnaire regarding demographics, lifestyle, medical, surgical and reproductive history. Significant variables on the univariate analysis were analyzed by multivariate analysis using a forward step-wise logistic regression model., Results: Dyslipidaemia was found in 69.4% of patients, 60% of FDR and 40.9% of controls (p < 0.0001 and p = 0.003 respectively), autoimmune diseases in 36.9% of patients, 30.4% of FDR and 13.4% of controls (p < 0.0001 and p = 0.011 respectively). Hashimoto's disease (p = 0.003), Raynaud syndrome (p = 0.023) and Sjögren syndrome (p = 0.044) were significantly associated with PBC. On multivariate analysis statistically significant associations were found with primary educational level (AOR 2.304, 95% CI 1.024-5.181), cholecystectomy (AOR 2.927, 95% CI 1.347-6.362) and the presence of at least another autoimmune disease (AOR 3.318, 95% CI 1.177-6.22). Cancer history was more frequent in patients than in controls (p = 0.033). Familial PBC was found to be 9.9%., Conclusions: Dyslipidaemia and autoimmune diseases were significantly increased not only in patients as expected but also in their FDR. An increased prevalence of malignancies was found in patients. Primary educational level, cholecystectomy and the presence of at least another autoimmune disease were found as putative risk factors for PBC. No association was found with smoking, urinary tract infection or reproductive history. The reported high familial occurrence of PBC could imply screening with AMA of FDR with at least another autoimmune disease.

Patients with primary Raynaud's phenomenon may have a genetically determined risk for clotting factors that predispose them to aberrant microvascular thrombosis. We investigated the prevalence of factor V substitution of G to A at position 1691 (FVLeiden), prothrombin G20210A, and methyltetrahydrofolate reductase C677T mutations in these patients. Two hundred (158 women, 42 men, mean age of 42.4 ± 13.7 years) consecutive patients with primary Raynaud's phenomenon and 200 age-sex-matched healthy controls of Hungarian origin were included in a case-control study. The prevalence of methyltetrahydrofolate reductase C677T homozygous among patients was significantly lower than in the control group (odds ratio 0.4, 95% confidence interval 0.2-0.9, P < 0.05). The prevalence of other thrombosis-associated alleles did not differ between patients with primary Raynaud's phenomenon and control subjects. FVLeiden, prothrombin G20210A, and polymorphism, prothrombin G20210A mutations have no apparent effect on the etiology of primary Raynaud's phenomenon.

The COL4A1 gene encodes the α1-chain of type IV collagen, which is ubiquitously expressed in basement membranes. Mutations in COL4A1 have been reported in autosomal-dominant porencephaly and in patients with symptomatic small vessel brain disease, inconstantly associated with eye defects. We have previously reported three COL4A1 mutations associated with a systemic phenotype that we called HANAC (Hereditary Angiopathy, Nephropathy, Aneurysms, and Cramps). We carried out a clinical and genetic study of three families presenting with characteristic features of HANAC syndrome. Common systemic signs included arterial retinal tortuosity and muscle cramps, with a variable combination of small vessel brain disease, Raynaud phenomena, and kidney defects. Three novel COL4A1 missense substitutions are described, which affect highly conserved glycine residues within the collagenous domain of the protein. All six known mutations associated with the HANAC phenotype are localized within the CB3[IV] fragment of COL4A1, which encompasses major integrin-binding sites. Our results confirm that HANAC syndrome is a distinct clinical entity within the COL4A1-related disorders, which is characterized by systemic involvement and usually asymptomatic brain disease. The restricted distribution of COL4A1 mutations within the CB3[IV] region is a characteristic of the reports of patients with HANAC, which suggests that abnormal cell-type IV collagen interactions may underlie the systemic defects observed in this syndrome., (Copyright © 2010 Wiley-Liss, Inc.)

Objective: To investigate the familiality of systemic sclerosis (SSc) in relation to Raynaud's phenomenon (RP) (a marker of vasculopathy), other autoimmune inflammatory disease, and fibrotic interstitial lung disease (ILD)., Methods: A genealogic resource, the Utah Population Database (UPDB), was used to test heritability of RP, other autoimmune disease, and ILD. Diseases were defined by International Classification of Diseases, Ninth Revision codes and identified from statewide discharge data, the University of Utah Health Science Center Enterprise Data Warehouse, and death certificates and were linked to the UPDB for analysis. Familial standardized incidence ratio (FSIR), relative risks (RRs) to first-, second-, third-, and fourth-degree relatives for SSc, RP, other autoimmune disease, and ILD (with 95% confidence intervals [95% CIs]), and population attributable risk (PAR) were calculated., Results: A software kinship analysis tool was used to analyze 1,037 unique SSc patients. Fifty SSc families had significant FSIRs, ranging from 2.07 to 17.60. The adjusted PAR was approximately 8%. The RRs were significant for other autoimmune disease in the first-degree relatives (2.49 [95% CI 1.99-3.41], P = 2.42 x 10(-15)) and second-degree relatives (1.48 [95% CI 1.34-2.39], P = 0.002), for RP in first-degree relatives (6.38 [95% CI 3.44-11.83], P = 4.04 x 10(-9)) and second-degree relatives (2.39 [95% CI 1.21-4.74], P = 0.012), and for ILD in first-degree relatives (1.53 [95% CI 1.04-2.26], P = 0.03), third-degree relatives (1.47 [95% CI 1.18-1.82], P = 0.0004), and fourth-degree relatives (1.2 [95% CI 1.06-1.35], P = 0.004)., Conclusion: These data suggest that SSc pedigrees include more RP, autoimmune inflammatory disease, and ILD than would be expected by chance. In SSc pedigrees, genetic predisposition to vasculopathy is the most frequent risk among first-degree relatives.

Objective: Serotonin is a key contributing factor in pulmonary arterial hypertension (PAH) by inducing pulmonary arterial smooth muscle cell (PA-SMC) proliferation. This relates specifically to the internalization process in PA-SMC of the serotonin transporter (SLC6A4 or 5-HTT). A long (L)/short (S) (44 base pair insertion) functional polymorphism within the promoter of the transporter SLC6A4 gene has been reported to be associated with familial and idiopathic PAH. Our objective was to determine whether polymorphisms of SLC6A4 confer susceptibility to SSc and its vascular phenotype., Methods: Three Tag single-nucleotide polymorphisms (SNP) (rs2066713, rs1042173, rs6354) chosen using Hapmap and linkage disequilibrium data were genotyped in a total cohort of 667 SSc patients (56 with PAH, 207 with digital ulcerations) and 447 controls. All individuals were of French Caucasian origin. L/S polymorphism genotyping was determined by polymerase chain reaction in a random subgroup of 364 SSc patients (34 with PAH, 138 with digital ulcerations) and 218 controls., Results: Three polymorphisms (L/S, rs2066713, rs1042173) were in Hardy-Weinberg equilibrium in the control population, but rs6354 deviated. Allelic and genotypic frequencies for these 3 polymorphisms were similar in SSc patients and controls. Subphenotype analyses of subsets with PAH and digital ulceration did not detect any difference between SSc patients compared to controls., Conclusion: These results from a large cohort of European Caucasian SSc patients do not support the implication of SLC6A4 in the pathogenesis of SSc and its vascular subphenotypes. However, serotonin pathways remain good candidates to contribute to the vasculopathy of SSc.

Systemic lupus erythematosus (SLE) is a chronic and progressive autoimmune disease in which reactive oxygen species contribute to pathogenesis. We analysed the distribution of manganese superoxide dismutase (MnSOD2) 47C>T (Ala-9Val) functional polymorphic variants within the mitochondrial targeting sequence in SLE patients (n = 102) and controls (n = 199). We did not find significant differences in the distribution of MnSOD2 47C>T polymorphic variants in SLE patients and controls. However, we found that MnSOD2 Val/Val genotype (recessive model) showed a significant association with Raynaud's phenomenon, odds ratio (OR) = 12.000 [95% confidence interval (CI) = 2.315-62.193], p = 0.0015. We also found that the MnSOD2 Val/Val genotype contributes to immunologic manifestations, OR = 2.957 (95% CI = 1.207-7.243), p = 0.0222, and anti-dsDNA antibody presence OR = 3.365 (95% CI = 1.364-8.304), p = 0.0107, in patients. Our observations indicate that MnSOD2 Val/Val variant can be linked to some clinical manifestations in patients with SLE.

Objective: To investigate the frequency of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism genotypes in patients with systemic lupus erythematosus (SLE), and to study the correlation between I/D polymorphism of the ACE gene and the clinical manifestations of SLE, especially vascular involvement, lupus nephritis and disease severity., Methods: The frequency of ACE gene I/D polymorphism genotypes was determined in 92 patients with SLE from Kuwait, and compared to that in 100 ethnically matched healthy controls using the polymerase chain reaction., Results: The distribution of ACE I/D polymorphism and allele frequencies in SLE patients was not significantly different from controls. Further analyses of SLE patients showed that there was a significant association between DD genotype and Raynaud's phenomenon (p=0.008, odd ratio=5.4, 95% confidence interval: 1.6-18.6). However, there was no significant association between the ACE genotype and lupus nephritis or disease severity., Conclusion: No difference was found between the distribution of the ACE genotype in SLE patients and the general pop-ulation in Kuwait. However, the presence of the DD genotype may confer susceptibility to the development of vascular morbidity.

The pathophysiology of primary Raynaud's phenomenon (Raynaud's disease) remains uncertain but the transmission of this primary microcirculatory dysregulation seems strongly influenced by genetic factors. For a long time, physicians have found that the hereditary factor plays an important role in the genesis of Raynaud's disease. Familial analysis and twin studies have confirmed the role of an hereditary factor. It seems heterogeneous but pedigree analysis indicates the possibility of an autosomal dominant transmission influenced by sex, in some families, allowing an approach called "reverse genetic" based on linkage analysis. Such an approach has focused on few loci but sequencing of candidate genes for genetic mutations remains negative. Given the supposed heterogeneity of the genetic transmission of Raynaud's disease, diversification of strategies in molecular genetics is suitable with reference to techniques applied to multifactorial heredity.

Occupational vinyl chloride monomer (VCM) exposure can induce Raynaud's phenomenon (RP). However, not all VCM workers developed RP, which suggests an underlying genetic susceptibility. Genetic polymorphisms of glutathione S-transferases (GSTs), involved in VCM metabolism, have been shown to influence certain VCM-related health effects. We have conducted a case-control study of 58 subjects with RP along with 247 subjects without RP, from a population of 305 French workers exposed or formerly exposed to VCM, to assess any association between GST M1 and GST T1 gene polymorphisms, either separately or in combination, and the presence of RP. None of the GST M1 or GST T1 genotypes were significantly associated with the presence of RP among studied VCM workers. A combination of positive genotypes for both GST M1 and GST T1 was significantly associated with RP presence, compared to the other combinations of genotypes (OR=2.1, 95% CI=1.1-3.8). OR adjusted for age, smoking status, alcohol consumption and history of treated hypertension did not reach significance (OR=2.0, 95% CI=0.9-5.2). None of the GST M1 and GST T1 genotypes seem to contribute separately to the presence of RP, suggesting that they are not, when taken alone, a major determinant of interindividual variability for VCM-induced PR. However, the combination of both positive GST M1 and GST T1 genotypes appears to contribute slightly to susceptibility to RP in VCM-exposed subjects. Nevertheless, our study-the first to examine the role of a genetic component in the occurrence of RP secondary to occupational exposure to a chemical-corroborates the previous considerations that interaction between the genetic constitution and environmental factors is of importance in determining the health-adverse effects of VCM exposure.

Previously, we described a large Dutch family with hereditary vascular retinopathy (HVR), Raynaud's phenomenon and migraine. A locus for HVR was mapped on chromosome 3p21.1-p21.3, but the gene has not yet been identified. The fact that all three disorders share a vascular aetiology prompted us to study whether the HVR haplotype also contributed to Raynaud's phenomenon and migraine in this family. Whereas the parent-child transmission disequilibrium test (TDT) did not reach significance, the sibling TDT revealed that the HVR haplotype harbours a susceptibility factor for Raynaud's phenomenon and migraine. Identification of the HVR gene will improve the understanding of the pathophysiology of HVR, Raynaud's phenomenon and migraine.

Unlabelled: We report a case of two siblings with Raynaud phenomena and migraine, whose symptoms were successfully treated with pizotifen., Conclusion: To our knowledge, this is the first case documenting the association between Raynaud phenomena and migraine in two siblings with a family history of Raynaud phenomena and ischaemic heart disease.

Background: Leiomyomatosis peritonealis disseminata (LPD) is defined as the occurrence of multiple tumorous intraabdominal lesions, which are myomatous nodules. LPD is a rare disease with only about 100 cases reported. The usual course of LPD is benign with the majority of the patients being premenopausal females. Only two cases involving men have been reported, no syndrome or familial occurrence of LPD has been described., Case Presentation: We describe a Caucasian-American family in which six members (three men) are diagnosed with Leiomyomatosis peritonealis disseminata (LPD) and three deceased family members most likely had LPD (based on the autopsy reports). Furthermore we describe the association of LPD with Raynaud's syndrome and Prurigo nodularis., Conclusion: Familial clustering of Leiomyomatosis peritonealis disseminata (LPD) has not been reported so far. The etiology of LPD is unknown and no mode of inheritance is known. We discuss possible modes of inheritance in the presented case, taking into account the possibility of a genetic syndrome. Given the similarity to other genetic syndromes with leiomyomatosis and skin alterations, we describe possible similar genetic pathomechanisms.

Background: Certain conditions characterised by blood vessel occlusion or vascular spasm have been found to cluster together in epidemiological studies. However the biological causes for these associations remain controversial. This study used a classical twin design to examine whether these conditions are linked through shared environmental exposures or by a common underlying genetic propensity to vasospasm., Methods: We investigated the association between hypertension, migraine, Raynaud's phenomenon and coronary artery disease in twins from a national register. Phenotype status was determined using a questionnaire and the genetic and environmental association between phenotypes was estimated through variance components analysis., Results: Responses were obtained from 2,204 individuals comprising 525 monozygotic and 577 dizygotic pairs. There was a significant genetic contribution to all four traits with heritabilities ranging from 0.34 to 0.64. Multivariate model-fitting demonstrated that a single common genetic factor underlies the four conditions., Conclusions: We have confirmed an association between hypertension, migraine, Raynaud's phenomenon and coronary artery disease, and shown that a single genetic factor underlies them. The demonstration of a shared genetic factor explains the association between them and adds weight to the theory of an inherited predisposition to vasospasm.

We evaluated the occurrence of spontaneous chromosome damage in cultured peripheral lymphocytes of subjects with idiopathic and pre-scleroderma Raynaud's phenomenon, by means of molecular cytogenetic analysis. Using the micronucleus assay as a marker of chromosome alteration, we studied 30 patients with pre-scleroderma Raynaud's phenomenon, 30 patients with idiopathic Raynaud's phenomenon and 30 healthy subjects. All subjects were classified as ANA-, ACA+ or Scl 70+. To identify the mechanism of micronucleus formation, fluorescence in situ hybridisation analysis was also performed. Pre-scleroderma Raynaud's phenomenon subjects showed significantly higher micronucleus frequencies than idiopathic Raynaud's phenomenon subjects and controls (37.0 +/- 11.5 vs. 11.1 +/- 3.2 and 10.7 +/- 2.7 respectively p < 0.0001). Interestingly, subjects with idiopathic Raynaud's phenomenon displayed micronucleus frequency comparable to that of healthy controls. Furthermore, ACA+ subjects showed the highest micronucleus frequencies (41.0 +/- 7.6) as compared to subjects with Scl 70+ antibody (25.0 +/- 3.5). Our results show that circulating lymphocytes of only pre-scleroderma Raynaud's phenomenon subjects undergo chromosomal damage, as detected by the micronucleus assay, at a higher rate than expected. No prevalence of aneuploidogenic or clastogenic events in micronucleus formation is revealed by fluorescence in situ hybridisation analysis.

Objective: To evaluate the prevalence of spontaneous chromosome damage in cultured peripheral lymphocytes of patients with systemic sclerosis (SSc), idiopathic Raynaud's phenomenon (RP), and suspected secondary RP, by means of molecular cytogenetic analysis., Methods: We studied 43 patients with SSc, 13 with idiopathic RP, and 16 with suspected secondary RP and 25 healthy controls. As a marker of chromosome alteration we used the micronucleus (MN) assay. All subjects were also classified for antinuclear antibodies, anticentromere antibodies (ACA), or Scl70. To identify the mechanism of MN formation, we also performed MN fluorescence in situ hybridization (FISH) analysis using a pancentromeric DNA probe., Results: Patients with SSc and subjects with RP showed significantly higher MN frequencies than controls (25.9 +/- 1.7 and 19.1 +/- 2.15, respectively, vs 9.4 +/- 2.2; p < 0.001). Subjects with suspected secondary RP displayed MN frequency (23.5 +/- 2.7) comparable to that of SSc patients, while spontaneous MN level in idiopathic RP subjects (13.6 +/- 3.0) did not differ significantly from controls (9.4 +/- 2.2). ACA positive subjects showed the highest MN frequencies (32.8 +/- 1.7) compared to subjects with a different antibody pattern (18.3 +/- 1.6)., Conclusion: Our results show the presence of higher levels of micronuclei in circulating lymphocytes of patients with SSc and subjects with suspected secondary RP. They also suggest a possible role of ACA in determining cytogenetic anomalies. FISH analysis indicated that both aneuploidogenic and clastogenic events contributed to the formation of MN observed in SSc patients and subjects with suspected secondary RP.

Objective: To evaluate the prevalence of spontaneous chromosome damage in cultured peripheral lymphocytes of subjects with suspected presclerodermic Raynaud's phenomenon (RP), by means of molecular cytogenetic analysis., Methods: We studied 20 suspected presclerodermic RP, 20 idiopathic RP and 25 healthy subjects. As marker of chromosome alteration we used the micronucleus assay. All subjects were also classified as ANA-, ACA+ or Scl70+. To identify the mechanism of MN formation, a MN fluorescence in situ hybridisation (FISH) analysis using a pancentromeric DNA probe was also performed., Results: Suspected presclerodermic RP subjects, showed significantly higher MN frequencies than idiopathic RP and controls (39+/-15.2 vs 10+/-2.1 and 9.8+/-3.5 respectively p<0.0001). Interestingly, subjects with idiopathic RP displayed MN frequency comparable to that of controls. Furthermore, ACA+ subjects showed the highest MN frequencies (44+/-8.1) as compared to subjects with different antibody pattern (26+/-7.1)., Conclusions: Our results show the presence of higher levels of chromosomal damage in circulating lymphocytes of suspected presclerodermic RP. They also would suggest a key role of anti-centromere antibody in determining the observed cytogenetic anomalies. FISH analysis indicated that both aneuploidogenic and clastogenic events contribute to the formation of MN observed in suspected presclerodermic RP.

Objective: Fibroblasts from patients with systemic sclerosis (SSc) have an activated phenotype characterized by increased synthesis of extracellular matrix (ECM) components. SPARC (secreted protein, acidic and rich in cysteine) regulates the deposition or assembly of ECM components. The aim of this study was to investigate the role of SPARC in SSc susceptibility by functional and genetic association studies., Methods: Complementary DNA (cDNA) microarrays were used to obtain gene expression data on cultured dermal fibroblasts from SSc patients. SPARC protein levels were assessed by Western blotting. Five polymorphic microsatellite markers within 5 cM of the SPARC gene (chromosome 5q31-32) were genotyped in Choctaw Indians, a population previously shown to have a high prevalence of SSc. Discovery of single-nucleotide polymorphisms (SNPs) was accomplished by sequencing the SPARC cDNA. These SNPs were then genotyped in a multi-ethnic cohort of SSc patients to determine potential associations with disease susceptibility in a broader population of SSc patients, as well as with various clinical and immunologic features of SSc. The functional relevance of these SNPs with regard to transcript stability of SPARC was also assessed., Results: Microarrays demonstrated increased expression of SPARC, along with other ECM genes, in SSc patients compared with normal controls. SSc fibroblasts also had increased SPARC protein levels. Three of 5 microsatellite markers near SPARC showed significant associations with SSc in the Choctaw SSc patients. Sequencing of SPARC cDNA revealed 3 novel SNPs in the 3'-untranslated region at +998 (C-->G), +1551 (C-->G), and +1922 (T-->G). Homozygosity for the C allele at SNP +998 was significantly increased in SSc patients across ethnic lines. SPARC SNPs +1551 and +1922 demonstrated correlations with Raynaud's phenomenon and pulmonary fibrosis, respectively. Functional studies of SPARC SNP +998 in normal fibroblast cultures suggested a correlation between the SNP +998 C allele polymorphism and an increased messenger RNA half-life., Conclusion: This study is the first to show that polymorphisms of the SPARC gene are associated with susceptibility to, and clinical manifestations of, SSc and that they may also be functionally important in influencing SPARC expression in skin fibroblasts.

We performed a genomewide search for linkage in an extended Dutch family with hereditary vascular retinopathy associated with migraine and Raynaud phenomenon. Patients with vascular retinopathy are characterized by microangiopathy of the retina, accompanied by microaneurysms and telangiectatic capillaries. The genome search, using a high throughput capillary sequencer, revealed significant evidence of linkage to chromosome 3p21.1-p21.3 (maximum pairwise LOD score 5.25, with D3S1578). Testing of two additional families that had a similar phenotype, cerebroretinal vasculopathy, and hereditary endotheliopathy with retinopathy, nephropathy, and stroke, revealed linkage to the same chromosomal region (combined maximum LOD score 6.30, with D3S1588). Haplotype analysis of all three families defined a 3-cM candidate region between D3S1578 and D3S3564. Our study shows that three autosomal dominant vasculopathy syndromes with prominent cerebroretinal manifestations map to the same 3-cM interval on 3p21, suggesting a common locus.

Objective: To investigate whether patients with systemic sclerosis (SSc) have raised homocysteine (Hcy) plasma levels, thought to be an independent risk factor for vascular disease, and to study the relationship between Hcy and endothelial damage, and between Hcy and methylene-tetrahydrofolate reductase (MTHFR) genotypes, and patients' vitamin nutritional status, which are among the more frequent causes of hyperhomocysteinemia., Methods: We measured Hcy, von Willebrand factor (vWF), folic acid, and vitamin B12 plasma levels and analyzed the frequencies of MTHFR mutations in 30 patients with SSc and 12 patients with primary Raynaud's phenomenon (RP); 29 healthy subjects served as controls., Results: Patients with SSc had higher Hcy and vWF concentrations than those with RP (p < 0.01 and p < 0.02, respectively) or controls (p < 0.02 and p < 0.0001, respectively). Folic acid and vitamin B12 were lower in SSc than in RP (p < 0.01 and p < 0.02, respectively) or controls (p < 0.05). MTHFR genotype did not influence Hcy, folate, or vitamin B12 concentrations, but patients homozygous for the mutant gene had higher vWF levels., Conclusion: Patients with SSc, but not those with RP, had significantly higher Hcy and vWF plasma levels. Nutritional rather than inherited factors seem to have a pathogenic role in SSc hyperhomocysteinemia.

There is increasing evidence that genetic factors play important roles in susceptibility to and expression of systemic sclerosis (SSc), as well as primary Raynaud phenomenon. Familial aggregation for SSc, although infrequent (1.2%-1.5% of SSc families), has now been established, and when compared with population prevalence represents a significant risk factor for the disease and lays a firmer foundation for genetics in etiopathogenesis. Major histocompatibility complex class II alleles increase disease risk in some populations but are more strongly correlated with specific autoantibody profiles. Microchimerism influenced by human leukocyte antigen also remains an intriguing hypothesis. A variety of extracellular matrix genes, including fibrillin-1, have become additional candidates for contributing to what is likely a complex genetic disease. Reviewed here is evidence relating to these concepts, especially new data reported over the last year.

Objective: To identify chromosomal regions containing genes involved in the susceptibility to primary Raynaud's phenomenon (RP)., Methods: Six extended families with multiple individuals affected with primary RP (n = 37) were examined for linkage in a 2-stage, whole-genome screen, using a total of 298 microsatellite markers., Results: Multipoint, nonparametric linkage analysis identified 5 areas of possible linkage, with a nominal level of significance of P < or = 0.05. Analysis of a finer map of markers in these regions defined the regions of linkage as 21.4 cM on 6q13-6q23.3 (D6S261; P = 0.0004), 10.2 cM on 7p22-7p15 (D7S664; P = 0.014), 1.6 cM on 9p23-9p22 (D9S156; P = 0.0075), 5.1 cM on 17p13.1-17p12 (D17S1791; P = 0.036), and 11.8 cM on Xp11.4-Xp11.23 (DXS8054; P = 0.006). Three potential candidate genes map to these regions: the beta subunit of the muscle acetylcholine receptor and the serotonin 1B and 1E receptors., Conclusion: These results provide evidence of the presence and location of genes that are involved in the genetic susceptibility to primary RP.

Objectives: To elucidate possible genetic factors involved in the pathogenesis of primary Raynaud's phenomenon (RP) and to determine the demographic features., Methods: The allele frequencies of known polymorphisms in four vasoactive candidate genes, eNOS, BKRG, ET-1 and the ETA receptor genes, were compared in a phenotypically homogeneous group of patients with primary RP and a normal control population., Results: In patients with primary RP, there was a higher reporting of both a family history of RP than in controls (45.3% vs 3.1%; P<0.0001) and a personal history of migraine (32.6% vs 7.2%; P<0.0001). No significant differences in allele frequencies of the candidate genes were found., Conclusions: These findings support the concept that genetic susceptibility exists in primary RP. The high prevalence of migraine suggests that primary RP is part of a more widespread disorder of vascular tone. These findings do not suggest that common molecular variants of these candidate genes are involved in primary RP.

We describe an extended Dutch family with a new hereditary disorder: autosomal dominant vascular retinopathy, migraine and Raynaud's phenomenon. Information was obtained on 289 family members (151 males, 138 females), of whom 198 were personally interviewed. Retinopathy was found in 20 (6.9%) of the family members, migraine in 65 (22.5%) and Raynaud's phenomenon in 50 (17.3%). A combination of all three symptoms was found in 11 subjects. In a genetic linkage analysis we firstly excluded several candidate loci. Subsequently, 75% of the autosomal genome was excluded in a genome-wide search. The following conclusions were drawn. First, genetic factors are involved in Raynaud's phenomenon. Secondly, the genetic linkage of migraine with vascular retinopathy and Raynaud's phenomenon supports a vascular aetiology of this disorder. Finding the gene for this family may help to elucidate the genetic background of migraine and of vascular disorders in general.

Objective: To determine the occurrence of familial aggregation of primary Raynaud's disease., Methods: Twenty-three patients with primary Raynaud's disease and their first-degree relatives were assessed by questionnaire and, when possible, by physical examination. The same procedures were performed on the patients' spouses and the spouses' first-degree relatives, who served as the control group., Results: The prevalence of Raynaud's disease was significantly higher in the families of the probands than in the control families when assessed by questionnaire (26.1% versus 5.5%; P < 10(-5)), and by physical examination (11.2% versus 2.8%; P = 0.015)., Conclusion: These findings demonstrate that there is significant familial aggregation of primary Raynaud's disease.

Many authors consider that late onset is a suspect criterion for differentiating primary Raynaud's phenomenon (Raynaud's disease, RD) from Raynaud's syndrome (RS). However, many cases of late-onset Raynaud's phenomenon in patients over forty years of age remain without etiologic diagnosis and therefore deserve the designation "late-onset RD." One hundred and ninety-four patients with RD (143 women, 51 men) were selected among 424 patients with Raynaud's phenomenon, according to Allen and Brown's criteria with negative serologic investigations and normal capillaroscopy. The purpose of the study was to consider the possible discriminant value of age of onset in distinguishing between RD and RS. The following epidemiologic features were studied: age of onset, sex, family history of Raynaud's phenomenon and migraine, and smoking and working habits. Microcirculation was assessed by capillaroscopy and strain-gauge plethysmography. Maximal digital flow at 45 degrees C and reactivity to cold were determined for each patient. Results were related to age of onset. The existence of true cases of late-onset RD in patients over forty years of age was confirmed (prevalence 27%), showing a correlation with a family history of Raynaud's phenomenon inferior to that found in early-onset cases (p < 0.0001). Microcirculation studies generally indicated a strong correlation between reactivity to cold, familial RD, and early onset, whereas no correlation was found with migraine or smoking. Nor was there any clinical or plethysmographic evidence for arteritis as a possible pathogenetic factor in late-onset RD. These results indicate that late-onset RD is a valid designation and that its pathogenesis seems less dependent on genetic sensitivity to cold than that of early-onset cases. In the absence of underlying arteritis, neurovascular dysfunction or a hemorheologic mechanism may be suggested as plausible causes of late-onset RD.

Two sisters had autoimmune responses to the U1RNP particle that were quantitatively similar and/or identical in molecular characteristics. No other autoantibodies were demonstrable. Both sisters immunoprecipitated only U1RNA, had a reaction of identity in gel diffusion, bound the 68-kDa band in HeLa cell extract in Western blot, and reacted almost equally to a rabbit anti-idiotypic reagent made against either sister's isolated anti-U1RNP Fab fragments. They both carried a DR4 allele, which has been associated with anti-U1RNP production in several studies. While the sisters both had Raynaud's phenomenon, their clinical pictures were otherwise dissimilar. One had a seizure disorder (Ju); the other had polymyositis and features of scleroderma (Je). In sister Ju, Raynaud's phenomenon was manifest for the first time in association with the appearance of precipitating anti-U1RNP.

We have isolated and characterized a set of overlapping cDNA clones that encode the human centromere autoantigen centromere protein C (CENP-C). The identity of these clones has been established using several criteria. First, they were shown to encode a polypeptide that migrates at the expected position for CENP-C on SDS-polyacrylamide gel electrophoresis. Second, we have demonstrated that this polypeptide shares at least two epitopes with human CENP-C. Polyclonal antibodies were raised to fusion proteins encoded by nonoverlapping regions of the cDNA clones. These antibodies were shown to recognize a protein at a position appropriate for CENP-C on immunoblots of human chromosomal proteins. In addition, we used indirect immunofluorescence to demonstrate that these antibodies recognize centromeres of HeLa chromosomes in the expected pattern for CENP-C. Localization of CENP-C by immunoelectron microscopy reveals that this protein is a component of the inner kinetochore plate.