The Caveolin-3 P104L mutation of LGMD-1C leads to disordered glucose metabolism in muscle cells.

Caveolin-3 (CAV3) is a muscle specific protein that plays an important role in maintaining muscle health and glucose homeostasis in vivo. A novel autosomal dominant form of LGMD-1C in humans is due to a P104L mutation within the coding sequence of the human CAV3 gene. The mechanism by which the LGMD-1C mutation leads to muscle weakness remains unknown. Our objective was to determine whether muscle weakness was related to the imbalance of glucose metabolism. We found that when the P104L mutation was transiently transfected into C2C12 cells, there was decreased glucose uptake and glycogen synthesis after insulin stimulation. Immunoblotting analysis showed that the P104L mutation resulted in decreased expression of CAV3, CAV1 and pAkt. Confocal immunomicroscopy indicated that the P104L mutation reduced CAV3 and GLUT4 in the cell membrane, which accumulated mainly near the nucleus. This work is the first report of an association between muscle weakness due to LGMD-1C and energy metabolism. The P104L mutation led to a decrease in C2C12 muscle glucose uptake and glycogen synthesis and may be involved in the pathogenesis of LGMD-1C.

A novel MVK missense mutation in one Chinese family with disseminated superficial actinic porokeratosis.

Disseminated superficial actinic porokeratosis (DSAP) is a severe chronic autosomal dominant cutaneous disorder with high genetic heterogeneity. mevalonate kinase, (MVK) a gene know to play an important role in regulation of calcium-induced keratinocyte differentiation and proliferation, has recently been suggested as the disease-causing gene for DSAP. Here we report a direct sequencing analysis of this gene in 3 DSAP families, 6 sporadic cases, and 100 unrelated healthy controls. We detected a heterozygous T to A transition at nucleotide 205 in exon 3 of MVK gene in one familial case. This mutation will result in an amino acid change at codon 69 (P.Ser69Thr), which is from a serine codon (TCA) to a threonine codon (ACA). No such mutation was detected in the unaffected family members or the 100 unrelated healthy controls. Our results demonstrated a novel missense mutation in MVK gene. This will be valuable for the diagnosis of DSAP as well as for genetic counseling and prenatal diagnosis of affected families.

One novel susceptibility locus associate with systemic lupus erythematosus in Chinese Han population.

The aim of the study is to explore additional susceptibility factors for systemic lupus erythematosus (SLE) in Chinese Hans. Based on our previous GWAS of SLE, we performed a multistage replication study involving 3,152 cases and 7,050 controls from China to identify additional susceptibility loci for SLE by using the Sequenom MassArray system. All Chinese Han samples used in this study were obtained from doctors through collaboration with multiple hospitals in two geographic regions (central and southern China). Single-marker association analyses were performed using logistic regression with gender as a covariate in each case-control cohort. The joint analysis of all combined samples was performed using logistic regression with gender and sample cohorts as covariates. The significant association evidence for rs906868 (OR = 1.14, 95% CI 1.08-1.20, P combined = 7.71 × 10(-10)) and rs7579944 (OR = 1.13, 95% CI 1.07-1.19, P combined = 5.55 × 10(-9)) was observed, which located at 2p23.1. In this region, limb bud and heart development homolog (LBH) was the only gene indicated, suggesting LBH might be a susceptibility gene for SLE, although its function was still unknown. The results indicated that the SNP rs7579944, rs906868 at 2p23.1 showed significant association with SLE. The genes LBH which located in this loci might be the predisposing genes of SLE.

Genomewide association study of leprosy.

BACKGROUND: The narrow host range of Mycobacterium leprae and the fact that it is refractory to growth in culture has limited research on and the biologic understanding of leprosy. Host genetic factors are thought to influence susceptibility to infection as well as disease progression. METHODS: We performed a two-stage genomewide association study by genotyping 706 patients and 1225 controls using the Human610-Quad BeadChip (Illumina). We then tested three independent replication sets for an association between the presence of leprosy and 93 single-nucleotide polymorphisms (SNPs) that were most strongly associated with the disease in the genomewide association study. Together, these replication sets comprised 3254 patients and 5955 controls. We also carried out tests of heterogeneity of the associations (or lack thereof) between these 93 SNPs and disease, stratified according to clinical subtype (multibacillary vs. paucibacillary). RESULTS: We observed a significant association (P<1.00x10(-10)) between SNPs in the genes CCDC122, C13orf31, NOD2, TNFSF15, HLA-DR, and RIPK2 and a trend toward an association (P=5.10x10(-5)) with a SNP in LRRK2. The associations between the SNPs in C13orf31, LRRK2, NOD2, and RIPK2 and multibacillary leprosy were stronger than the associations between these SNPs and paucibacillary leprosy. CONCLUSIONS: Variants of genes in the NOD2-mediated signaling pathway (which regulates the innate immune response) are associated with susceptibility to infection with M. leprae.

Evidence basis for using dexmedetomidine to enhance the quality of paravertebral block: A systematic review and meta-analysis of randomized controlled trials.

Background: Dexmedetomidine is considered an adjunct to local anaesthesia (LA) to prolong peripheral nerve block time. However, the results from a previous meta-analysis were not sufficient to support its use in paravertebral block (PVB). Therefore, we performed an updated meta-analysis to evaluate the efficacy of dexmedetomidine combined with LA in PVB. Methods: We performed an electronic database search from the date of establishment to April 2022. Randomized controlled trials (RCTs) investigating the combination of dexmedetomidine and LA compared with LA alone for PVB in adult patients were included. Postoperative pain scores, analgesic consumption, and adverse reactions were analyzed. Results: We identified 12 trials (701 patients) and found that the application of dexmedetomidine as a PVB adjunct reduced the postoperative pain severity of patients 12 and 24 h after surgery compared to a control group. Expressed as mean difference (MD) (95% CI), the results were -1.03 (-1.18, -0.88) (p < 0.00001, I2 = 79%) for 12 h and -1.08 (-1.24, -0.92) (p < 0.00001, I2 = 72%) for 24 h. Dexmedetomidine prolonged the duration of analgesia by at least 173.27 min (115.61, 230.93) (p < 0.00001, I2 = 81%) and reduced postoperative oral morphine consumption by 18.01 mg (-22.10, 13.92) (p < 0.00001, I2 = 19%). We also found no statistically significant differences in hemodynamic complications between the two groups. According to the GRADE system, we found that the level of evidence for postoperative pain scores at 12 and 24 h was rated as moderate. Conclusion: Our study shows that dexmedetomidine as an adjunct to LA improves the postoperative pain severity of patients after surgery and prolongs the duration of analgesia in PVB without increasing the incidence of adverse effects.

A single-nucleotide polymorphism of the TNFSF4 gene is associated with systemic lupus erythematosus in Chinese Han population.

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. Recently, single-nucleotide polymorphisms (SNPs) in tumor necrosis factor (TNF) superfamily gene TNFSF4 have been shown to be associated with SLE in European and Hong Kong Chinese populations. But it is unknown whether it is also associated with the disease in Mainland Chinese Han population. We genotyped the SNPs rs1234315 near the TNFSF4 gene in 1,344 SLE patients and 4,315 controls of Chinese Han population and confirmed the association between the SNP and the SLE [odds ratios (ORs) of 1.45 and P values of 1.5 × 10(-16)]. The stratification analyses showed that rs1234315 was more strongly associated with SLE patients with arthritis. Our study not only suggested that the TNFSF4 gene was associated with SLE in Chinese Han population, but also implied that it might be a common genetic factor predisposing to the development of SLE in multiple populations.

A single-nucleotide polymorphism of the TNFAIP3 gene is associated with systemic lupus erythematosus in Chinese Han population.

Systemic lupus erythematosus (SLE) is a complex systemic disease influenced by genetic and environmental factors. The exact pathogenesis of SLE is still unknown. Recently, several genome-wide association studies (GWA) in European population have found many novel susceptibility genes for SLE including TNFAIP3. In order to examine whether TNFAIP3 is associated with SLE in Chinese Han population, we genotyped one of its non-synonymous mutation SNP rs2230926, showing significant association evidence with SLE in European population, with 1,420 cases and 4,461 controls of Chinese Han by using Sequenom MassArray system. Highly significant association between SNP rs2230926 and SLE of Chinese Han was detected [OR = 1.65, 95% confidence interval (CI): 1.392-1.986, P = 2.03 x 10(-8)]. Interestingly, rs2230926 of TNFAIP3 was also associated with arthritis, ANA and some other subphenotypes of the disease. Our findings suggest that SNP rs2230926 in the TNFAIP3 might be a common genetic factor for SLE within different populations in terms of Chinese Han and European population.

Nitrogen-doped MoS2 quantum dots: Facile synthesis and application for the assay of hematin in human blood.

Nitrogen-doped MoS2 quantum dots (N-MoS2 QDs) were synthesized via a facile hydrothermal approach, and exhibited high fluorescence quantum yield (QY, 14.9%), excellent photostability, biocompatibility and water solubility. A novel method with good selectivity and sensitivity was established to assay hematin using N-MoS2 QDs as a fluorescent probe based on inner filter effect (IFE). Fluorescent quenching of N-MoS2 QDs has a fine linear dependence with the concentration of hematin in the range of 0.5-15 µmol/L and a limit of detection of 0.32 µmol/L (S/N = 3). By the detection method, average concentration of hematin in real health human erythrocytes was measured as 22.5 ± 3.9 µmol/L. And, recoveries range varied from 94 to 108% through standard recovery experiment. The N-MoS2 QDs probe shows excellent photostability, low cytotoxicity and anti-interference ability for hematin assay, which may become a promising method for the test of hematin in human blood.

Association of HLA-DQA1 and DQB1 alleles with keloids in Chinese Hans.

BACKGROUND: Some studies have suggested that human HLA status might potentiate development of keloids phenotype, and exists ethnic differences. No report has been published about HLA-DQA1 and DQB1 alleles associated with keloids in Chinese Hans. OBJECTIVES: To investigate whether HLA-DQA1 and DQB1 alleles are associated with genetic susceptibility to keloids in Chinese Hans. METHODS: Polymerase chain reaction-sequence-specific primer (PCR-SSP) method was used to analyze the distribution of HLA-DQA1 and DQB1 alleles among 192 patients with keloids and 273 healthy controls in Chinese Hans. RESULTS: (1) The frequencies of HLA-DQA1*0104, DQB1*0501 and DQB1*0503 (OR = 2.13, P(c) = 0.0063; OR = 14.42, P(c) < 10(-7) and OR = 6.09, P(c) < 10(-7), respectively) were significantly higher, while the frequencies of DQA1*0501, DQB1*0201 and DQB1*0402 (OR = 0.46, P(c) = 0.0099; OR = 0.24, P(c) < 10(-4) and OR = 0.10, P(c)=0.0054, respectively) were lower in patients than in controls. (2) In this study significant susceptibility haplotypes to keloids were DQA1*0104-DQB1*0501 and DQA1*0104-DQB1*0503. (3) HLA-DQB1*0501 and DQB1*0503 were positively associated with all subgroups of keloid patients. However, the DQA1*0104 (OR = 2.51, P(c) = 0.0009; OR = 2.22, P(c) = 0.0090 and OR = 2.20, P(c) = 0.0117, respectively) was only prevalent in keloid patients with single site, moderate severity and negative family history. (4) HLA-DQB1*0201 (OR = 0.27, P(c) = 0.0018 and OR = 0.27, P(c) = 0.0012, respectively) and DQB1*0402 (OR = 0.07, P(c) = 0.0270 and OR = 0.07, P(c) = 0.0306, respectively) were negatively associated with moderate severity and negative family history in keloids, moreover, HLA-DQB1*0201 (OR = 0.23, P(c) = 0.0003) and DQA1*0501 (OR = 0.43, P(c) = 0.0234) were less prevalent in patients with single site. CONCLUSION: This study demonstrated the positive association of HLA-DQA1 and DQB1 alleles and haplotypes with keloids.

Genomic risk variants at 3q22.3 are associated with keloids in a Chinese Han population.

A keloid is the process of skin healing, collagen synthesis and metabolism of the loss of normal control in a sustained hyperactive state, resulting in excessive proliferation of collagen fibers. A large-scale genome-wide association study (GWAS) has identified multiple single nucleotide polymorphisms (SNPs) in the 3q22.3 loci that are associated with keloids in a Japanese population. However, the associations of SNPs in 3q22.3 with keloids were not confirmed in a selected Chinese population by a replication study. Thus, in the present study, the relationships between keloids and 3q22.3 were assessed in another independent Chinese Han population, including 309 keloid patients and 1080 control subjects. The results displayed that rs940187 was associated with keloids (OR=1.88, 95% CI 1.27-2.78, P=1.35E-3) and remained significant after Bonferroni's correction for multiple testing, while rs1511412 showed only a trend association (OR=2.23, 95% CI 1.09-4.55, P=0.02) with keloids. In addition, we subsequently checked the annotation datasets for rs940187 with eQTLs and obtained two hits, trans-proteins SLC7A9 and LEMD3, with significant P values less than 1e-4. In summary, genomic risk variants at 3q22.3 are associated with keloids in a Chinese Han population and contribute to the development and deterioration of the keloids, together with environmental factors.

Association between peroxisome proliferator-activated receptor-gamma coactivator-1alpha gene polymorphisms and type 2 diabetes in southern Chinese population: role of altered interaction with myocyte enhancer factor 2C.

BACKGROUND: Some single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha gene have been reported to be associated with type 2 diabetes in different populations, and studies on Chinese patients yielded controversial results. The objective of this case-control study was to explore the relationship between SNPs of PGC-1alpha and type 2 diabetes in the southern Chinese population and to determine whether the common variants: Gly482Ser and Thr394Thr, in the PGC-1alpha gene have any impacts on interaction with myocyte enhancer factor (MEF) 2C. METHODS: The SNPs in all exons of the PGC-1alpha gene was investigated in 50 type 2 diabetic patients using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and direct sequencing. Thereafter, 263 type 2 diabetic patients and 282 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A bacterial two-hybrid system and site-directed mutagenesis were used to investigate whether Gly482Ser and Thr394Thr variants in the PGC-1alpha gene alter the interaction with MEF2C. RESULTS: Three frequent SNPs (Thr394Thr, Gly482Ser and Thr528Thr) were found in exons of the PGC-1alpha gene. Only the Gly482Ser variant had a different distribution between diabetic patients and healthy subjects, with the 482Ser allele more frequent in patients than in controls (40.1% vs 29.3%, P < 0.01). Even in controls, the 482Ser (A) carriers were more likely to have higher levels of total cholesterol and low-density lipoprotein cholesterol than the 482Gly (G) carriers. The 394A-482G-528A haplotype was associated with protection from diabetes, while the 394A-482A-528A was associated with the susceptibility to diabetes. The bacterial two-hybrid system and site-directed mutagenesis revealed that the 482Ser variant was less efficient than the 482Gly variant to interact with MEF2C, whereas the 394Thr (A) had a synergic effect on the interaction between 482Ser variant and MEF2C. CONCLUSIONS: The results suggested that the 482Ser variant of PGC-1alpha conferred the susceptibility to type 2 diabetes in the southern Chinese population. The underlying mechanism may be attributable, at least in part, to the altered interaction between the different variants (Gly482Ser, Thr394Thr) in the PGC-1alpha gene and MEF2C.

[The cSNPs analysis in whole extron-wide of PGC-1alpha gene in Chinese population and the domain MEF2C bioinformatics study].

OBJECTIVE: To analyze distribution characteristics of PGC-1alpha gene coding single nucleotide polymorphisms (cSNPs), and to investigate the association between cSNPs and type 2 diabetes mellitus, and to study biological information about PGC-1alpha domain muscle enhancer factor 2C (MEF2C) in Chinese Han population. METHODS: These cSNPs were identified by means of polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA direct sequencing technology in a total of 263 type 2 diabetic patients and 282 normal glucose tolerant controls. The possible association was analyzed between type 2 diabetes mellitus and the specific cSNPs and their haplotypes by case-control method. The tertiary structure of PGC-1alpha domain MEF2C was predicated and analyzed for possible biological information by a series of bioinformatics soft wares. RESULTS: Four variants were found in whole extron-wide of PGC-1alpha gene in Chinese Han diabetic population. They were 394G/A, 482G/A, 528A/G and 612C/T. The 482G/A polymorphism was remarkably associated with type 2 diabetes (chi2 = 14.2025, P= 0.0002). Haplotypes analysis shown that distribution frequency of haplotypes had a statistical difference between type 2 diabetes mellitus and normal glucose tolerance control groups (chi2 = 59.9, P< 0.01) and haplotype 394A-482A-528A had a linkage disequilibrium with type 2 diabetes (t= 2.361, P< 0.05). The tertiary simulant structure of PGC-1alpha domain MEF2C was established successfully by computer. The 482G/A variant accompanied with hydrogen bonds breaking might decrease hydrophobicity and lead to an incompact space configuration which was very critical to function. CONCLUSION: The 482G/A variant could decrease binding force between PGC-1alpha and MEF2C and increase the risk of type 2 diabetes in Chinese Han population by PGC-1alpha -MEF2C-GLUT-4 pathway.

[Genetical diagnosis in a family with X-linked hypohidrotic ectodermal dysplasia].

OBJECTIVE: To identify the mutations of ED1 gene in a family with X-linked hypohidrotic ectodermal dysplasia METHODS: Eight coding exons of ED1 gene of two patients with clinically confirmed X-linked hypohidrotic ectodermal dysplasia, their parents, and 100 unrelated population-matched control were amplified by polymerase chain reaction. The products were further analyzed by direct sequencing. RESULTS: Two patients with X-linked hypohidrotic ectodermal dysplasia in this pedigree showed a point mutation at nucleotide 1 045 ( A > G) . Meanwhile, heterozygous double peaks of nucleotide G and A at the same position were found in their mother, but not in their father and 100 unrelated population-matched controls. CONCLUSION: The c. 1 045A > G mutation of ED1 gene may be the pathologic cause of this Chinese family with X-linked hypohidrotic ectodermal dysplasia.

Estrogen receptor alpha gene polymorphism associated with type 2 diabetes mellitus and the serum lipid concentration in Chinese women in Guangzhou.

BACKGROUND: Estrogen might play an important role in type 2 diabetes mellitus pathogenesis. A number of polymorphisms have been reported in the estrogen receptor alpha (ERalpha) gene (also named ESR1), including the XbaI and PvuII restriction enzyme polymorphisms of ESR1, which may be involved in disease pathogenesis. The aim of this study was to determine whether ERX gene polymorphisms are associated with type 2 diabetes mellitus and serum lipid level. METHODS: Two hundred and ninety-nine patients with type 2 diabetes mellitus were compared with three hundred and forty-one health controls of Guangzhou in China, both were male and postmenopausal female residents at 51 - 70 years. ESR1 genotyping was performed using polymerase chain reaction (PCR) and PvuII and XbaI restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: ESR1 allelic frequencies of P, p and X, x alleles were 0.408, 0.592; 0.360, 0.640 in the type 2 diabetes mellitus group and 0.318, 0.682; 0.328, 0.672 in the control group, respectively. In case-control study, there was significant difference in PvuII, but not XbaI, allele frequency between the type 2 diabetes mellitus and control groups (P = 0.001 and P = 0.122). When the group was separated into men and women, the difference was significant in women (P < 0.001) but not in men (P = 0.854) with the PvuII genotype, and the effect of PvuII variant on the development of type 2 diabetes mellitus was improved with aging. In addition, PvuII genotype was associated with blood glucose [fasting blood glucose (FBG), postprandial blood glucose (PBG)] and serum lipid [total cholesterol (TC) and low density lipoprotein (LDL)-c] concentration in healthy women. CONCLUSIONS: PvuII polymorphism of ESR1 increases susceptibility to type 2 diabetes mellitus in Chinese Guangzhou women. ESR1 variants may also impact serum lipid metabolism, which might provide a mechanism connecting ESR1 to type 2 diabetes.

Phylogenetic analysis of basic helix-loop-helix transcription factors in the genome of a typical human-disease vector.

Ixodes scapularis, the black-legged tick, is one of the most common human-disease vectors and transmits Borrelia species, such as B. burgdorferi, as well as Theileria microti, Anaplasma phagocytophilum, etc. As basic helix-loop-helix (bHLH) transcription factors have been recognized for many years as important regulators of various developmental processes, we performed phylogenetic analysis of the black-legged tick genome in order to identify the number and family of bHLH transcription factors. Because bHLH family members have been identified in many organisms, including silkworm and fruit fly, we were able to conduct this survey and identify 58 putative bHLH transcription factors. Phylogenetic analysis revealed that the black-legged tick has 26, 10, 9, 1, 9, and 1 member in groups A, B, C, D, E, and F, respectively, whereas two were orphan genes. This analysis also revealed that unlike silkworm and fruit fly, the black-legged tick has no Mesp, Mlx, or TF4 family members, but has one more MyoRb family member. The present study provides useful background information for future studies of the black-legged tick as a disease vector with the goal of prevention and treatment.

NEDD4 single nucleotide polymorphism rs2271289 is associated with keloids in Chinese Han population.

Keloids are abnormally raised fibroproliferative lesions that usually occur following cutaneous traumas. Recently, a large-scale genome-wide association study (GWAS) has identified multiple single nucleotide polymorphisms (SNPs) in three genetic loci that are associated with keloids in Japanese population. Subsequently, two reported loci 1q41 (rs873549 and rs1442440) and 15q21.3 (rs2271289) for keloids were confirmed in selected Chinese population. The association of these SNPs with clinical features of keloids, has not yet been studied. To explore the role of these SNPs in the pathogenesis of keloids, we performed a case-controlled study in another independent Chinese Han population to analyze the correlation between 4 SNPs (rs873549, rs2118610, rs1511412, rs2271289) and keloids phenotypes. 309 keloids patients and 1080 control subjects were included. The results showed that, in the dominant mode of inheritance, the minor allele T of SNP rs2271289 had significantly higher odd ratios (ORs) in the severe keloid group compared with both the controls and the mild keloid group. The ORs were maintained after Bonferroni's correction (OR: 4.09, 95% CI: 1.78-9.37, P-value 3.25E-04). The ratio of the severe: mild OR for rs2271289 (dominant model) is (4.73/1.84=2.57). Similar associations in SNP rs2271289 were seen for groups with no family history and multiplesite compared with the control groups. No associations between keloid number, family history or severity relative to the controls were observed for the other three SNPs. Our data support that rs2271289 is strongly associated with severe keloids and might contribute to the complexity of clinical features of keloids.

Clinical and epidemiological analysis of keloids in Chinese patients.

Keloids are common abnormally raised fibroproliferative lesions that can occur following even minor cutaneous trauma. There are limited data on Chinese patients with keloids, and the purpose of our study was to investigate the clinical and epidemiological features of keloids in Chinese patients. Assessment was performed by unified, designed questionnaires. A total of 715 patients were enrolled and statistical analysis and heritability were performed using EPI INFO 6.0, SPSS13.0 and Falconer's method. Keloids occurred typically between the ages of 10 and 30 years, and the mean age of initial onset was 21.14 ± 13.45 years in females and 22.55 ± 11.36 years in males. The difference in the mean age of onset was not significant between males and females (p > 0.05). A greater severity of keloids was observed in the positive history family group than in the negative history family group, and this difference was statistically significant (χ (2) = 10.889, p < 0.05). The formation of keloids in multiple anatomical sites was found to be significant in the positive family history group. This difference was statistically significant (χ (2) = 15.47, p < 0.001). The prevalence of keloids in first-, second- and third-degree relatives of the proband with keloids was 7.62, 0.38 and 0.035 %, respectively. These results were higher than those in controls and the difference of the prevalence rates of first- and second-degree relatives between probands and controls was significant (χ (2) = 224.63 and 12.078, respectively, p < 0.001). The heritability of keloids in first-, second- and third-degree relatives was 72.45, 40.55 and 17.07 %, respectively. Our findings revealed that the most severe forms of keloids were observed in the probands with positive family history, and the heritability in first-degree relatives of probands was 72.45 %. It is certain, therefore, that genetic factors play a role in the hereditary composition of keloids.

Detection of a novel missense mutation in the mevalonate kinase gene in one Chinese family with DSAP.

Disseminated superficial actinic porokeratosis (DSAP) is the most common form of porokeratosis and a severe chronic autosomal dominant cutaneous disorder with high genetic heterogeneity. Recently, the mevalonate kinase (MVK) gene has been identified as a candidate gene responsible for DSAP and multiple mutations have been reported. Here, we report identification of a novel missense mutation in the MVK gene in a Chinese family with DSAP. A 50-year-old male was diagnosed as proband of DSAP based on the clinical and histological findings, which show numerous hyperpigmented macules by physical examination and cornoid lamella by skin biopsy. Similar skin symptoms were also observed in his father, who died many years ago. We prepared genomic DNA from the proband, unaffected individuals from his family members, as well as 100 unrelated healthy controls. PCR was then conducted using the above genomic DNA as template and the MVK gene-specific primers. The PCR product was subjected to direct sequencing and the sequence was compared to that of MVK gene within the NCBI database. We detected a heterozygous C to G transition at nucleotide 643 in exon 7 of MVK gene of the proband. This will result in an amino acid change at codon 215 (P.Arg215Gly.), which is from an arginine codon (CGA) to a Glycine codon (GGA). We did not detect any mutation in the unaffected family members or the 100 unrelated healthy controls, demonstrating that this is a novel missense mutation in MVK gene and therefore, contributes to the molecular diagnosis of DSAP.

Association of HLA haplotype with keloids in Chinese Hans.

Keloids are common abnormal raised fibroproliferative lesions that can occur following even minor cutaneous trauma. Human leukocyte antigen (HLA) polymorphisms have shown strong association with susceptibility to keloids with different ethnic backgrounds. In this study, the polymerase chain reaction sequence-specific primer method was used to analyze the distribution of HLA haplotype in 192 patients with keloids and 252 healthy control individuals. Controls were matched by gender, age, and race. We compared haplotype between the two groups, and analyzed their association with keloids. The haplotype analysis revealed that three new two-locus haplotypes including B*07-DQB1*0501, B*07-DRB1*15, DQB1*0503-DRB1*15 (P<0.05) were associated with keloids, while two extended haplotypes B*07-Cw*0802-DQB1*0501 (P=0.0063) and Cw*0802-DQB1*0501-DRB1*15 (P=0.0121) were found to be related to keloids. This is the first detailed report to elucidate HLA haplotypes associated with keloids. Our results provide some information for future research on predisposing genes in major histocompatibility complex (MHC) regions in Chinese patients with keloids. In addition, the association of certain HLA haplotypes with susceptibility to keloids would provide clues in choosing proper preventive strategies.

Variants in MHC, LCE and IL12B have epistatic effects on psoriasis risk in Chinese population.

BACKGROUND: Psoriasis has long been considered as a complex disease, and gene-gene or gene-environment interactions may jointly influence the etiology for psoriasis. OBJECTIVE: We evaluated the associations of single nucleotide polymorphisms (SNPs) in MHC region, and determined the epistasis and combined effects of MHC locus and IL12B, LCE on risk for psoriasis. METHODS: We genotyped SNP rs1265181 (MHC) in 5067 cases and 6404 controls, combining with the prior GWAS data (1139 cases and 1132 controls), we explored the genetic interaction among MHC locus, LCE and IL12B by using logistic regression analysis. We evaluated the combined effects of MHC locus and two non-MHC loci in the combined sample of 6206 cases and 7536 controls. RESULTS: Extremely high significance of association was detected between rs1265181 and psoriasis (p combined < 10E--300, OR = 16.52, 95% CI: 15.28-18.44). We observed significant interactions between MHC and LCE (p = 0.0016) and between MHC and IL12B (p = 0.0036). The risk increased some 26-fold in individuals with risk alleles in both MHC and LCE as compared with those without risk alleles, and individual carrying risk alleles of MHC and IL12B has around 36-fold higher risk of psoriasis than those with protective alleles. CONCLUSIONS: This study provides evidence for the epistatic effects between MHC locus and LCE, IL12B genes. Besides, we suggest that MHC might be the main effect gene on the risk for psoriasis. This data may contribute to our understanding of psoriasis genetic interactions and account for the additional risk of certain patients to develop psoriasis.