Functional analysis of the HGSNAT gene in patients with mucopolysaccharidosis IIIC (Sanfilippo C Syndrome)

Mucopolysaccharidosis (MPS) IIIC is an autosomal recessive lysosomal storage disorder caused by a deficiency in heparan acetyl CoA: α‐glucosaminide N‐acetyltransferase (HGSNAT). The characteristic feature is the deterioration of the central nervous system, but other symptoms may include coarse facies, developmental delay, macrocrania and motor retardation. HGSNAT is localised to the lysosomal membrane and catalyses a transmembrane acetylation in which the terminal glucosamine residue of heparan sulphate acquires an acetyl group, thus forming N‐acetylglucosamine. 54 variants of the HGSNAT gene have been identified in MPS IIIC patients thus far, 22 of which are missense mutations. In this study, 20 of the latter were introduced into the cDNA of HGSNAT, and the resultant derivatives were exogenously expressed in cell culture. Transfection of 16 of these resulted in the synthesis of negligible HGSNAT protein and activity. The levels and function of the remaining 4 mutants, however, were similar to those of exogenously expressed wild‐type HGSNAT. Interestingly, c.1209G>T (p.W403C), which is present in a variant classified in the former category, has only been sequenced in alleles also possessing c.1843G>A (p.A615T), which independently has a negligible effect on HGSNAT expression. This report suggests that these may function together to abolish HGSNAT activity. © 2010 Wiley‐Liss, Inc.     

Mutational analysis of the HGSNAT gene in Italian patients with mucopolysaccharidosis IIIC (Sanfilippo C syndrome)

Mucopolysaccharidosis (MPS) describes any inherited lysosomal storage disorder resulting from an inability to catabolize glycosaminoglycans. MPS III (or Sanfilippo syndrome) is an autosomal recessive disease caused by a failure to degrade heparan sulphate. There are four subtypes of MPS III, each categorized by a deficiency in a specific enzyme involved in the heparan sulphate degradation pathway. The genes mutated in three of these (MPS IIIA, MPS IIIB, and MPS IIID) have been cloned for some time. However, only very recently has the gene for MPS IIIC (heparin acetyl CoA: α‐glucosaminide N‐acetyltransferase, or HGSNAT) been identified. Its product (previously termed transmembrane protein 76, or TMEM76) has little sequence similarity to other proteins of known function, although it is well conserved among all species. In this study, a group of MPS IIIC patients, who are mainly of Italian origin, have been clinically characterized. Furthermore, mutational analysis of the HGSNAT gene in these patients resulted in the identification of nine alleles, of which eight are novel. Three splice‐site mutations, three frameshift deletions resulting in premature stop codons, one nonsense mutation, and two missense mutations were identified. The latter are of particular interest as they are located in regions which are predicted to be of functional significance. This research will aid in determining the molecular basis of HGSNAT protein function, and the mechanisms underlying MPS IIIC. © 2007 Wiley‐Liss, Inc.     

Molecular analysis of Sanfilippo syndrome type C in Spain: seven novel HGSNAT mutations and characterization of the mutant alleles

Canals I, Elalaoui SC, Pineda M, Delgadillo V, Szlago M, Jaouad IC, Sefiani A, Chabás A, Coll MJ, Grinberg D, Vilageliu L. Molecular analysis of Sanfilippo syndrome type C in Spain: seven novel HGSNAT mutations and characterization of the mutant alleles. The Sanfilippo syndrome type C [mucopolysaccharidosis IIIC (MPS IIIC)] is caused by mutations in the HGSNAT gene, encoding an enzyme involved in heparan sulphate degradation. We report the first molecular study on several Spanish Sanfilippo syndrome type C patients. Seven Spanish patients, one Argentinean and three Moroccan patients were analysed. All mutant alleles were identified and comprised nine distinct mutant alleles, seven of which were novel, including four missense mutations (p.A54V, p.L113P, p.G424V and p.L445P) and three splicing mutations due to two point mutations (c.633+1G>A and c.1378‐1G>A) and an intronic deletion (c.821‐31_821‐13del). Furthermore, we found a new single nucleotide polymorphism (SNP) (c.564‐98T>C). The two most frequent changes were the previously described c.372‐2A>G and c.234+1G>A mutations. All five splicing mutations were experimentally confirmed by studies at the RNA level, and a minigene experiment was carried out in one case for which no fibroblasts were available. Expression assays allowed us to show the pathogenic effect of the four novel missense mutations and to confirm that the already known c.710C>A (p.P237Q) is a non‐pathogenic SNP. Haplotype analyses suggested that the two mutations (c.234+1G>A and c.372‐2A>G) that were present in more than one patient have a common origin, including one (c.234+1G>A) that was found in Spanish and Moroccan patients.     

Mutational analysis of the HGSNAT gene in Italian patients with mucopolysaccharidosis IIIC (Sanfilippo C syndrome). Mutation in brief #959. Online

Mucopolysaccharidosis (MPS) describes any inherited lysosomal storage disorder resulting from an inability to catabolize glycosaminoglycans. MPS III (or Sanfilippo syndrome) is an autosomal recessive disease caused by a failure to degrade heparan sulphate. There are four subtypes of MPS III, each categorized by a deficiency in a specific enzyme involved in the heparan sulphate degradation pathway. The genes mutated in three of these (MPS IIIA, MPS IIIB, and MPS IIID) have been cloned for some time. However, only very recently has the gene for MPS IIIC (heparin acetyl CoA: alpha-glucosaminide N-acetyltransferase, or HGSNAT) been identified. Its product (previously termed transmembrane protein 76, or TMEM76) has little sequence similarity to other proteins of known function, although it is well conserved among all species. In this study, a group of MPS IIIC patients, who are mainly of Italian origin, have been clinically characterized. Furthermore, mutational analysis of the HGSNAT gene in these patients resulted in the identification of nine alleles, of which eight are novel. Three splice-site mutations, three frameshift deletions resulting in premature stop codons, one nonsense mutation, and two missense mutations were identified. The latter are of particular interest as they are located in regions which are predicted to be of functional significance. This research will aid in determining the molecular basis of HGSNAT protein function, and the mechanisms underlying MPS IIIC.     

Identification of 16 sulfamidase gene mutations including the common R74C in patients with mucopolysaccharidosis type IIIA (Sanfilippo A)

Mucopolysaccharidosis type IIIA (MPS IIIA or Sanfilippo A disease) is a storage disorder caused by deficiency of the lysosomal enzyme sulfamidase. Mutation screening, using SSCP/heteroduplex analyses on cDNA and genomic DNA fragments, was performed in a group of 42 European patients. Sixteen of the 17 different gene mutations characterized have not been previously described. The spectrum of gene lesions consists of two 1-bp deletions (1091delC, 1093delG), an 18-bp duplication (421ins18), a splice site mutation (IVS2-2A→G), and 13 different missense point mutations. As in other lysosomal storage disorders, the phenotypic heterogeneity is associated with a considerable genetic heterogeneity. The missense mutation R74C, which alters an evolutionary conserved amino acid in the active site of the enzyme, was found on 56% of alleles of 16 Polish patients, whereas it was less frequent among German patients (21% of disease alleles). R245H, a previously reported common mutation, represents 35% of disease alleles in German patients, but only 3% in Polish patients. As the combined frequency of the common mutations (R74C and R245H) in German and Polish populations exceeds 55%, screening for these two mutations will assist molecular genetic diagnosis of MPS IIIA and allow heterozygote testing in these populations. Hum Mutat 10:479–485, 1997. © 1997 Wiley-Liss, Inc.     

糖尿病视网膜病变相关基因多态性的研究进展

糖尿病视网膜病变是目前国际上最主要的致盲性眼病之一,患病率日渐升高.其发生和发展与血糖水平、糖尿病病程、环境及遗传等多种因素有关.近些年来,随着基因多态性与糖尿病视网膜病变关系的研究不断深入和进展,已经筛选出了可能与之相关的数十 种基因,其中几种基因多态性已经被证实为糖尿病视网膜病变发生的独立危险因素.现将与糖尿病视网膜病变密切相关的基因多态性研究进展作一综述.     

Current understanding of genetics and genetic testing and information needs and preferences of adults with inherited retinal disease

Advances in sequencing technology and the movement of genetic testing into all areas of medicine will increase opportunities for molecular confirmation of a clinical diagnosis. For health-care professionals without formal genetics training, there is a need to know what patients understand about genetics and genetic testing and their information needs and preferences for the disclosure of genetic testing results. These topics were explored during face-to-face interviews with 50 adults with inherited retinal disease, selected in order to provide a diversity of opinions. Participants had variable understanding of genetics and genetic testing, including basic concepts such as inheritance patterns and the risk to dependents, and many did not understand the term ‘genetic counselling''. Most were keen for extra information on the risk to others, the process for genetic testing and how to share the information with other family members. Participants were divided as to whether genetic testing should be offered at the time of the initial diagnosis or later. Many would prefer the results to be given by face-to-face consultation, supplemented by further information in a format accessible to those with visual impairment. Health-care professionals and either leaflets or websites of trusted agencies were the preferred sources of information. Permission should be sought for disclosure of genetic information to other family members. The information needs of many patients with inherited retinal disease appear to be unmet. An understanding of their information needs and preferences is required to help health-care professionals provide optimal services that meet patient expectations.     

Perspectives of carriers of X-linked retinal diseases on genetic testing and gene therapy: A global survey

Female carriers of X-linked inherited retinal diseases (IRDs) are burdened with potentially passing their disease-causing variant to future generations, as well as exhibiting signs of retinal disease themselves. This study aimed to investigate carriers' experiences of genetic testing, emotions relating to having affected children, and their knowledge regarding genetic testing and gene therapy. An online survey was advertised to self-identified carriers worldwide. Two hundred and twenty-eight carriers completed the survey with mean age of 51 years (SD ± 15.0). A majority of respondents resided in the United States of America (51%), Australia (19%), and the United Kingdom (14%). Most carriers identified with feelings of guilt (70%), concern (91%), and anxiety (88%) for their child. Female carriers who had given birth to children had significantly greater gene therapy knowledge compared to carriers who had not (p < 0.05). Respondents agreed that their eyecare provider and general practitioner helped them understand their condition (63%), however, few carriers reported receiving psychological counselling (9%) or family planning advice (5%). Most respondents (78%) agreed that gene therapy should be available to carriers. This study emphasises the importance of providing appropriate counselling to female carriers and illustrates the motivation of many to participate in emerging treatment options, such as gene therapy.     

Clinical,biochemical, and molecular characterization of mucopolysaccharidosis type III in 34 Egyptian patients

Mucopolysaccharidosis type III (MPS III) is a rare autosomal recessive lysosomal storage disorder characterized by progressive neurocognitive deterioration. There are four MPS III subtypes (A, B, C, and D) that are clinically indistinguishable with variable rates of progression. A retrospective analysis was carried out on 34 patients with MPS III types at Cairo University Children's Hospital. We described the clinical, biochemical, and molecular spectrum of MPS III patients. Of 34 patients, 22 patients had MPS IIIB, 7/34 had MPS IIIC, 4/34 had MPS IIIA, and only 1 had MPS IIID. All patients presented with developmental delay/intellectual disability, and speech delay. Ataxia was reported in a patient with MPS IIIC, and cerebellar atrophy in a patient with MPS IIIA. We reported 25 variants in the 4 MPS III genes, 11 of which were not previously reported. This is the first study to analyze the clinical and genetic spectrum of MPS III patients in Egypt. This study explores the genetic map of MPS III in the Egyptian population. It will pave the way for a national registry for rare diseases in Egypt, a country with a high rate of consanguineous marriage and consequently a high rate of autosomal recessive disorders.     

Novel sequence variants in the TMIE gene in families with autosomal recessive nonsyndromic hearing impairment

To date, 37 genes have been identified for nonsyndromic hearing impairment (NSHI). Identifying the functional sequence variants within these genes and knowing their population-specific frequencies is of public health value, in particular for genetic screening for NSHI. To determine putatively functional sequence variants in the transmembrane inner ear (TMIE) gene in Pakistani and Jordanian families with autosomal recessive (AR) NSHI, four Jordanian and 168 Pakistani families with ARNSHI that is not due to GJB2 (CX26) were submitted to a genome scan. Two-point and multipoint parametric linkage analyses were performed, and families with logarithmic odds (LOD) scores of 1.0 or greater within the TMIE region underwent further DNA sequencing. The evolutionary conservation and location in predicted protein domains of amino acid residues where sequence variants occurred were studied to elucidate the possible effects of these sequence variants on function. Of seven families that were screened for TMIE, putatively functional sequence variants were found to segregate with hearing impairment in four families but were not seen in not less than 110 ethnically matched control chromosomes. The previously reported c.241C>T (p.R81C) variant was observed in two Pakistani families. Two novel variants, c.92A>G (p.E31G) and the splice site mutation c.212 −2A>C, were identified in one Pakistani and one Jordanian family, respectively. The c.92A>G (p.E31G) variant occurred at a residue that is conserved in the mouse and is predicted to be extracellular. Conservation and potential functionality of previously published mutations were also examined. The prevalence of functional TMIE variants in Pakistani families is 1.7% [95% confidence interval (CI) 0.3–4.8]. Further studies on the spectrum, prevalence rates, and functional effect of sequence variants in the TMIE gene in other populations should demonstrate the true importance of this gene as a cause of hearing impairment.     

A detailed clinical and molecular survey of subjects with nonsyndromic USH2A retinopathy reveals an allelic hierarchy of disease-causing variants

Defects in USH2A cause both isolated retinal disease and Usher syndrome (ie, retinal disease and deafness). To gain insights into isolated/nonsyndromic USH2A retinopathy, we screened USH2A in 186 probands with recessive retinal disease and no hearing complaint in childhood (discovery cohort) and in 84 probands with recessive retinal disease (replication cohort). Detailed phenotyping, including retinal imaging and audiological assessment, was performed in individuals with two likely disease-causing USH2A variants. Further genetic testing, including screening for a deep-intronic disease-causing variant and large deletions/duplications, was performed in those with one likely disease-causing change. Overall, 23 of 186 probands (discovery cohort) were found to harbour two likely disease-causing variants in USH2A. Some of these variants were predominantly associated with nonsyndromic retinal degeneration (‘retinal disease-specific''); these included the common c.2276 G>T, p.(Cys759Phe) mutation and five additional variants: c.2802 T>G, p.(Cys934Trp); c.10073 G>A, p.(Cys3358Tyr); c.11156 G>A, p.(Arg3719His); c.12295-3 T>A; and c.12575 G>A, p.(Arg4192His). An allelic hierarchy was observed in the discovery cohort and confirmed in the replication cohort. In nonsyndromic USH2A disease, retinopathy was consistent with retinitis pigmentosa and the audiological phenotype was variable. USH2A retinopathy is a common cause of nonsyndromic recessive retinal degeneration and has a different mutational spectrum to that observed in Usher syndrome. The following model is proposed: the presence of at least one ‘retinal disease-specific'' USH2A allele in a patient with USH2A-related disease results in the preservation of normal hearing. Careful genotype–phenotype studies such as this will become increasingly important, especially now that high-throughput sequencing is widely used in the clinical setting.     

Novel sequence variants of the alpha-galactosidase A gene in patients with Fabry disease

We carried out molecular studies of 15 unrelated Hungarian families diagnosed with Fabry disease (FD). Genetic analysis of the α-galactosidase A gene was performed in 22 hemizygous males and 34 females. One of the female patients with severe disease phenotype showed homozygosity for the recurrent c.644A > G mutation due to parental consanguinity. The c.644A > G mutation that has previously been found mostly in patients with the cardiac variant of FD, was associated with renal but not cardiac involvement in this female and in two other family members. In nine families, eight novel sequence variants such as small deletions (c.363delT, c.477delT, c.746delAC) and single nucleotide changes (c.107T > C, c.493G > C, c.796G > T, c.866T > G, c.871G > A) were found in addition to six previously described private mutations. This report contributes to the identification of novel disease-causing mutations in FD, and increases our knowledge on demographics and molecular characteristics of this rare lysosomal storage disorder. This is the first comprehensive overview of molecular genetic features of Hungarian patients with FD.     

The mutation p.Ser298Pro in the sulphamidase gene (SGSH) is associated with a slowly progressive clinical phenotype in mucopolysaccharidosis type IIIA (Sanfilippo A syndrome)

Mucopolysaccharidosis type IIIA (MPS IIIA, Sanfilippo A syndrome) is caused by mutations in the N-sulfoglucosamine sulfohydrolase (SGSH) gene and the resulting defective lysosomal degradation of the glycosaminoglycan heparan sulfate. The onset and progression of the disease are highly variable. Seventy-five mutations distributed over the SGSH gene have been described. We here report on the analysis of the natural course of the disease in 54 MPS IIIA patients through the use of a detailed questionnaire and four-point scoring system and an examination of the underlying mutations. By assessing the degree of developmental regression over time a group of seven patients with a slowly progressive course of the disease were identified. In these seven patients and in 3 other mildly affected patients the missense mutation c.892T>C (p.Ser298Pro) was found on one allele. These patients showed a lower frequency and later onset of the typical symptoms of the disease. The onset of regression in speech abilities and cognitive functions were delayed by 0.7 and 0.8 years, respectively, and the onset of regression of motor functions occurred 6.1 years later than in all other MPS IIIA patients. Severe regression in speech, cognitive and motor functions were delayed by 5, 5.9, and 11.2 years, respectively. These data suggest that in MPS IIIA patients carrying the mutation p.Ser298Pro a slowly progressive phenotype can be predicted and this may have an important impact on parental counselling and therapeutic interventions.     

RP2‐associated retinal disorder in a Japanese cohort: Report of novel variants and a literature review,identifying a genotype–phenotype association

The retinitis pigmentosa 2 (RP2) gene is one of the causative genes for X‐linked inherited retinal disorder. We characterized the clinical/genetic features of four patients with RP2‐associated retinal disorder (RP2‐RD) from four Japanese families in a nationwide cohort. A systematic review of RP2‐RD in the Japanese population was also performed. All four patients were clinically diagnosed with retinitis pigmentosa (RP). The mean age at examination was 36.5 (10–47) years, and the mean visual acuity in the right/left eye was 1.40 (0.52–2.0)/1.10 (0.52–1.7) in the logarithm of the minimum angle of resolution unit, respectively. Three patients showed extensive retinal atrophy with macular involvement, and one had central retinal atrophy. Four RP2 variants were identified, including two novel missense (p.Ser6Phe, p.Leu189Pro) and two previously reported truncating variants (p.Arg120Ter, p.Glu269CysfsTer3). The phenotypes of two patients with truncating variants were more severe than the phenotypes of two patients with missense variants. A systematic review revealed additional 11 variants, including three missense and eight deleterious (null) variants, and a statistically significant association between phenotype severity and genotype severity was revealed. The clinical and genetic spectrum of RP2‐RD was illustrated in the Japanese population, identifying the characteristic features of a severe form of RP with early macular involvement.     

Genetic heterogeneity and clinical variability in the Sanfilippo syndrome (types A, B, and C)

A study of 73 patients with the Sanfilippo syndrome (36 patients with Sanfilippo A disease, 23 with Sanfilippo B disease and 14 with Sanfilippo C disease) revealed both intertype and intratype variability. The course of the disease was relatively mild in Sanfilippo B disease and dementia was less severe. Type A showed earlier onset with more severe clinical manifestations and an earlier age at death. Sanfilippo C disease was slightly less severe than Sanfilippo A disease. The intratype variability may be explained in part by differences in genetic and environmental background. In Sanfilippo B disease, genetic heterogeneity is suggested by the observation of a more severe and a mild variant, and this variation may be due to the involvement of different allelic mutations. The intra-familial variability of the different types was small, but in three families with Sanfilippo B disease intrafamilial variability was evident.     

Molecular diagnostic workflow,clinical interpretation of sequence variants,and data repository procedures in 140 individuals with familial cerebral cavernous malformations

Familial cerebral cavernous malformation (FCCM) is an autosomal dominant vascular disorder caused by heterozygous deleterious variants in KRIT1, CCM2 or PDCD10. In a previous study, we presented the clinical and molecular findings in 140 FCCM individuals. In the present work, we report supporting information on (a) applied diagnostic workflow; (b) clinical significance of molecular findings according to the American College of Medical Genetics and Genomics/Association for Molecular Pathology recommendations; (c) standardization of molecular and clinical data according to the Human Phenotype Ontology; (d) preliminary genotype‐phenotype correlations on a subgroup of patients by considering sex, age at diagnosis, neurological symptoms, and number and anatomical site(s) of vascular anomalies; (e) datasets submitted to the Leiden Open Variation Database. An overview of the changes of our diagnostic approach before and after the transition to next‐generation sequencing is also reported. This work presents the full procedure that we apply for molecular testing, data interpretation and storing in public databases in FCCM.     

Scavenger receptor class B type I genetic variants associated with disease severity in chronic hepatitis C virus infection

Analysis of host genetic polymorphisms is an increasingly important tool for understanding and predicting pathogenesis and treatment response of viral diseases. The gene locus of scavenger receptor class B type I (SR-BI), encoding a cell entry factor and receptor for hepatitis C virus (HCV), contains several genetic polymorphisms. We applied a probe extension assay to determine the frequency of six single nucleotide polymorphisms (SNPs) within the SR-BI gene locus in 374 individuals with history of HCV infection. In addition, SR-BI messenger RNA (mRNA) levels were analyzed in liver biopsy specimens of chronically infected HCV subjects. The rs5888 variant allele T was present at a higher frequency in subjects with advanced fibrosis (χ², p = 0.016) and after adjusting for age, duration of infection and alcohol intake as confounding factors. Haplotype analysis of SNP frequencies showed that a haplotype consisting of rs61932577 variant allele C and rs5888 variant allele T was associated with an increased risk of advanced liver fibrosis (defined by an Ishak score 4−6) (adjusted odds ratio 2.81; 95% confidence interval 1.06−7.46. p = 0.038). Carriers of the rs5888 variant allele T displayed reduced SR-BI mRNA expression in liver biopsy specimens. In conclusion the rs5888 polymorphism variant is associated with decreased SR-BI expression and an increased risk of development of advanced fibrosis in chronic HCV infection. These findings provide further evidence for a role of SR-BI in HCV pathogenesis and provides a genetic marker for prediction of those infected individuals at greater risk of developing severe disease.     

Persistent mild hypothyroidism associated with novel sequence variants of the DUOX2 gene in two siblings

One of the steps in thyroid hormone biosynthesis is the generation of hydrogen peroxide by dual oxidases (DUOX). Only one study reported mutations in DUOX2 gene in congenital hypothyroidism (CH) associated with total iodide organification defect (TIOD) in homozygosity or with partial iodide organification defect (PIOD) in heterozygous patients. We report genetic and phenotypic characterization of a family affected with isolated CH. The proband was positive at neonatal TSH screening. High serum TSH with low FT4 confirmed the diagnosis. At 4 years, TSH was high after L-T(4) withdrawal and (123)I scintigraphy with perchlorate discharge test revealed a PIOD. His brother was negative at TSH screening, but perinatal iodine overload was documented by urinary test. Serum TSH was elevated at postnatal day 11 and progressively increased together with a decline in urinary iodine. Reevaluation at 4 years confirmed a persistent hyperthyrotropinemia associated with PIOD. Both siblings resulted compound heterozygotes for two novel DUOX2 variants, a nonsense mutation (c.2524C>T, p.Arg842X) and a missense substitution (c.1126C>T, p.Arg376Trp), undetected in 140 control alleles. The parents had normal thyroid function and were heterozygous carriers of mutant alleles. In conclusion, we report two novel sequence variants in DUOX2 gene that are associated with persistent mild hypothyroidism and PIOD in two siblings. Different neonatal iodine supply apparently acted as disease modifier, justifying the discrepant results at TSH screening in the two siblings with same DUOX2 genotype and suggesting that mild dyshormonogenic defects may remain undisclosed in areas characterized by elevated iodine intake.     

Lack of association of genetic variants in the LRP8 gene with familial and sporadic myocardial infarction

Coronary artery disease (CAD) and myocardial infarction (MI) have a genetic basis, but the precise genetic underpinning remains controversial. Recently, an association of the LRP8 R952Q polymorphism (rs5174) with familial premature CAD/MI was reported. We analysed rs5174 (or the perfect proxy rs5177) in 1,210 patients with familial MI and 1,015 controls from the German MI Family study, in 1,926 familial CAD (1,377 with MI) patients and 2,938 controls from the Wellcome Trust Case Control Consortium (WTCCC) MI/CAD cohort, in 346 CAD patients and 351 controls from the AtheroGene study and in 295 men with incident CAD and 301 controls from the Prospective Epidemiological Study of MI study and found no evidence for association in any of the populations studied. In the WTCCC and the German MI Family studies, additional single-nucleotide polymorphisms in the LRP8 gene were analysed and displayed no evidence for association either. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Wolfgang Lieb, Tanja Zeller, Massimo Mangino, Jeanette Erdmann, and Laurence Tiret contributed equally.     

Genetic variants of the class A scavenger receptor gene are associated with coronary artery disease in Chinese

The class A scavenger receptor,encoded by the macrophage scavenger receptor 1(MSR1) gene,is a pattern recognition receptor(PPR) primarily expressed in macrophages.It has been reported that genetic polymorphisms of MSR1 are significantly associated with the number of diseased vessels and coronary artery narrowing greater than 20% in Caucasians.However,whether it links genetically to coronary artery disease(CAD) in Chinese is not defined.Here,we performed an independent case-control study in a Chinese population consisting of 402 CAD cases and 400 controls by genotyping ten single nucleotide polymorphisms(SNPs) of MSR1.We found that rs416748 and rs13306541 were significantly associated with an increased risk of CAD with per allele odds ratio(OR) of 1.56 [95% confidence interval(CI) = 1.28-1.90;P < 0.001] and 1.70(95% CI = 1.27-2.27;P < 0.001),respectively.Our results indicate that genetic variants of MSR1 may serve as predictive markers for the risk of CAD in combination with traditional risk factors of CAD in Chinese population.