Clinical and Pathophysiological Features of High-altitude Pulmonary Edema in the Japanese Population: A Review of Studies on High-altitude Pulmonary Edema in Japan.

High-altitude pulmonary edema (HAPE) is a life-threatening, noncardiogenic pulmonary edema that occurs in unacclimatized individuals rapidly ascending to high altitudes above 2,500 m above sea level. Until the entity of HAPE was first identified in a case report published in Japan in 1966, the symptoms of severe dyspnea or coma occurring in climbers of the Japan Alps were incorrectly attributed to pneumonia or congestive heart failure. The Shinshu University Hospital serves as the central facility for rescuing and treating patients with HAPE in the region. Over the past 50 years, a series of studies have been conducted at Shinshu University to gain a better understanding of the characteristics of HAPE. This review summarizes the major achievements of these studies, including their clinical features, management, and pathogenesis of HAPE, particularly in the Japanese population.

Association of PDGFRA polymorphisms with the risk of corneal astigmatism in a Japanese population.

Corneal astigmatism is reportedly associated with polymorphisms of the platelet-derived growth factor receptor alpha (PDGFRA) gene region in Asian populations of Chinese, Malay, and Indian ancestry and populations of European ancestry. In this study, we investigated whether these PDGFRA polymorphisms are associated with corneal astigmatism in a Japanese population. We recruited 1,535 cases with corneal astigmatism (mean corneal cylinder power across both eyes: ≤ - 0.75 diopters [D]) and 842 controls (> - 0.75 D) to genotype 13 single-nucleotide polymorphisms (SNPs) in the PDGFRA gene region. We also performed imputation analysis in the region, with 179 imputed SNPs included in the statistical analyses. The PDGFRA SNPs were not significantly associated with the cases with corneal astigmatism ≤ - 0.75 D. However, the odds ratios (ORs) of the minor alleles of SNPs in the upstream region of PDGFRA, including rs7673984, rs4864857, and rs11133315, tended to increase according to the degree of corneal astigmatism, and these SNPs were significantly associated with the cases with corneal astigmatism ≤ - 1.25 D or ≤ - 1.50 D (Pc < 0.05, OR = 1.34-1.39). These results suggest that PDGFRA SNPs play a potential role in the development of greater corneal astigmatism.

HLA-G susceptibility to hepatitis B infection and related hepatocellular carcinoma in the Japanese population.

AIMS: Human leukocyte antigen (HLA)-G plays a role in various physiological immunomodulatory functions. Aberrant HLA-G expression is observed in various disease states, including tumors, autoimmune disorders, and viral infections. The present study investigated the association between HLA-G functional gene polymorphisms (rs1736933 [-486 C > A], rs1049033 [+2018 C > T], 14 bp Insertion [Ins]/Deletion [Del] [+2961 Del > Ins], and rs1063320 [+3142 C > G]) and disease susceptibility, hepatocellular carcinoma (HCC) development, and hepatitis B surface antigen (HBsAg) clearance. METHODS: Allele discrimination of the 3 SNPs (-486 C > A, +2018 C > T, +3142 C > G) was determined by a TaqMan 5' exonuclease assay, while the 14 bp Ins/Del polymorphism was typed by fragment analysis using Genetic Analyzer and GeneMapper software. The above polymorphisms were analyzed for 325 Japanese hepatitis B virus (HBV) patients, 355 Japanese healthy subjects (Controls) as healthy controls, and 799 Japanese hepatitis C virus (HCV) patients as disease controls, respectively. RESULTS: The 14 bp Insertion allele was significantly more frequent in HBV patients than Controls (27.1 % vs 20.6 %, odds ratio [OR] 1.43, P = 0.005) but did not differ between HCV patients and Controls. Similar results were found for the rs1063320 G allele (38.9 % vs 26.3 %, OR 1.78, P < 0.001) and the rs1736933 T allele (32.2 % vs 26.9 %, OR 1.29, P = 0.034) between HBV and Controls. The rs1049033 T allele showed a weak but significant association with HCC development in the dominant model (OR 1.95, P = 0.04). Regarding HBsAg clearance, the A allele at rs1736933 was significantly correlated in the recessive model (OR 3.23, P = 0.003). CONCLUSIONS: This study revealed significant associations of HLA-G gene polymorphisms with disease susceptibility, HCC development, and HBsAg clearance in HBV patients.

Amino acid polymorphisms in human histocompatibility leukocyte antigen class II and proinsulin epitope have impacts on type 1 diabetes mellitus induced by immune-checkpoint inhibitors.

Introduction: Immune-checkpoint inhibitors are effective in various advanced cancers. Type 1 diabetes mellitus induced by them (ICI-T1DM) is a serious complication requiring prompt insulin treatment, but the immunological mechanism behind it is unclear. Methods: We examined amino acid polymorphisms in human histocompatibility leukocyte antigen (HLA) molecules and investigated proinsulin epitope binding affinities to HLA molecules. Results and Discussion: Twelve patients with ICI-T1DM and 35 patients in a control group without ICI-T1DM were enrolled in the study. Allele and haplotype frequencies of HLA-DRB1*04:05, DQB1*04:01, and most importantly DPB1*05:01 were significantly increased in patients with ICI-T1DM. In addition, novel amino acid polymorphisms in HLA-DR (4 polymorphisms), in DQ (12 polymorphisms), and in DP molecules (9 polymorphisms) were identified. These amino acid polymorphisms might be associated with the development of ICI-T1DM. Moreover, novel human proinsulin epitope clusters in insulin A and B chains were discovered in silico and in vitro peptide binding assays to HLA-DP5. In conclusion, significant amino acid polymorphisms in HLA-class II molecules, and conformational alterations in the peptide-binding groove of the HLA-DP molecules were considered likely to influence the immunogenicity of proinsulin epitopes in ICI-T1DM. These amino acid polymorphisms and HLA-DP5 may be predictive genetic factors for ICI-T1DM.

The Contribution of Genetic Variants of the Peroxisome Proliferator-Activated Receptor-Alpha Gene to High-Altitude Hypoxia Adaptation in Sherpa Highlanders.

Kinota, Fumiya, Yunden Droma, Nobumitsu Kobayashi, Toshimichi Horiuchi, Yoshiaki Kitaguchi, Masanori Yasuo, Masao Ota, and Masayuki Hanaoka. The contribution of genetic variants of the gene encoding peroxisome proliferator-activated receptor-alpha gene (PPARA) to high-altitude hypoxia adaptation in Sherpa highlanders. High Alt Med Biol. 24:186-192, 2023.-Sherpa highlanders, who play invaluable roles in the exploration of Mount Everest, have exceptional tolerance to hypobaric hypoxia. Sherpa people are well known to possess the traits determined by genetic background for high-altitude adaptation. The metabolic adaptation mechanism is one of the biological ways for Sherpa highlanders in protecting them from hypoxia stress at high altitude. Studies have suggested that the gene encoding PPARA is associated with metabolic adaptation in the Himalayan population of Tibetans. This study attempts to investigate the genetic variants of the PPARA in Sherpa highlanders and the association with high-altitude hypoxia adaptation. Seven single-nucleotide polymorphisms (SNPs; rs135547, rs5769178, rs881740, rs4253712, rs5766741, and rs5767700 in introns and rs1800234 in exon 6) in the PPARA were genotyped in 105 Sherpa highlanders who lived in the Khumbu region (3440 m above sea level) and 111 non-Sherpa lowlanders who resided in Kathmandu (1300 m) in Nepal. By means of analyses of genetic distances, genotype distributions, allele frequencies, linkage disequilibrium, and haplotype constructions of the seven SNPs in the Sherpa highlanders versus the non-Sherpa lowlanders, it was revealed that the frequencies of minor alleles of rs4253712, rs5766741, rs5767700, and rs1800234 SNPs, as well as the frequency of haplotype constructed by the minor alleles of rs5766741-rs5767700-rs1800234, were significantly overrepresented in the Sherpa highlanders in comparison with the non-Sherpa lowlanders. The results strongly suggest that the genetic variants of the PPARA are likely to contribute to the high-altitude adaptation in Sherpa highlanders.

The blunted vascular endothelial growth factor-A (VEGF-A) response to high-altitude hypoxia and genetic variants in the promoter region of the VEGFA gene in Sherpa highlanders.

Background: Sherpa highlanders demonstrate extraordinary tolerance to hypoxia at high altitudes, which may be achieved by mechanisms promoting microcirculatory blood flow and capillary density at high altitudes for restoring oxygen supply to tissues. Vascular endothelial growth factors (VEGFs) are important signaling proteins involved in vasculogenesis and angiogenesis which are stimulated by hypoxia. We hypothesize that the VEGF-A, the major member of the VEGF family, and the gene encoding VEGF-A (VEGFA) play a part in the adaptation to high-altitude hypoxia in Sherpa highlanders. Methods: Fifty-one Sherpa highlanders in Namche Bazaar village at a high altitude of 3,440 meters (m) above sea level and 76 non-Sherpa lowlanders in Kathmandu city at 1,300 m in Nepal were recruited for the study. Venous blood was sampled to obtain plasma and extract DNA from each subject. The plasma VEGF-A concentrations were measured and five single-nucleotide polymorphisms (SNPs, rs699947, rs833061, rs1570360, rs2010963, and rs3025039) in the VEGFA were genotyped. The VEGF-A levels and allelic frequencies of the SNPs were compared between the two populations. Results: A significant difference in oxygen saturation (SpO2) was observed between the two ethnic groups locating at different elevations (93.7 ± 0.2% in Sherpas at 3,440 m vs. 96.7 ± 0.2% in non-Sherpas at 1,300 m, P < 0.05). The plasma VEGF-A concentration in the Sherpas at high altitude was on the same level as that in the non-Sherpas at low altitude (262.8 ± 17.9 pg/ml vs. 266.8 ± 21.8 pg/ml, P = 0.88). This result suggested that the plasma VEGF-A concentration in Sherpa highlanders was stable despite a high-altitude hypoxic stimulus and that therefore the Sherpas exhibited a phenotype of blunted response to hypoxic stress. Moreover, the allele frequencies of the SNPs rs699947, rs833061, and rs2010963 in the promoter region of the VEGFA were different between the Sherpa highlanders and non-Sherpa lowlanders (corrected P values = 3.30 ×10-5, 4.95 ×10-4, and 1.19 ×10-7, respectively). Conclusions: Sherpa highlanders exhibited a blunted VEGF-A response to hypoxia at high altitudes, which was speculated to be associated with the distinctive genetic variations of the SNPs and haplotype in the promoter region of VEGFA in Sherpa highlanders.

The levels of IL-1ß and soluble IL-1 receptors in patients with IgG4-related periaortitis/periarteritis.

PURPOSE: IgG4-related disease (IgG4-RD) is a chronic fibrotic inflammatory and an immune-mediated disease characterized by high serum IgG4 concentration and IgG4-bearing plasma cell infiltration in affected organs. IgG4-related periaortitis/periarteritis is a recently identified disease entity in IgG4-RD that affects the cardiovascular system, and its pathogenesis and characteristics remain unclear. The inflammatory cytokine IL-1ß is involved in a variety of cellular activities including inflammation, fibrosis, and angiogenesis. The present study compared the levels of the inflammatory cytokine IL-1ß and two soluble IL-1 receptors, IL-1R1 and IL-1R2, between IgG4-RD patients with and without IgG4-related periaortitis/periarteritis. METHODS: The patients with IgG4-related periaortitis/periarteritis (n â€‹= â€‹38), those without (n â€‹= â€‹66) and healthy (n â€‹= â€‹33) were recruited to measure cytokines of IL-1ß and soluble receptors (sIL-1R1 and sIL-1R2) in sera by ELISA assay. RESULTS: Serum IgG4 was significantly higher in patients with periaortitis/periarteritis compared to non-periaortitis/periarteritis (p â€‹= â€‹0.0074), while serum IL-1ß was significantly lower in patients with periaortitis/periarteritis (p â€‹= â€‹0.00037). The three groups did not show significant difference in sIL1-R1, while sIL-1R2 in the periaortitis/periarteritis and healthy group was higher than in the group without periaortitis/periarteritis (p â€‹= â€‹0.00001). CONCLUSIONS: The characteristic changes in IL-1ß, sIL-1R1, and sIL-1R2 levels in IgG4-RD patients with and without IgG4-related periaortitis/periarteritis may indicate an active phase of the inflammatory process in these diseases.

IL1R1 gene variants associate with disease susceptibility to IgG4-related periaortitis/periarteritis in IgG4-related disease.

BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated disorder characterized by high serum IgG4 concentration and IgG4-bearing plasma cell infiltration in affected organs. IgG4-related periaortitis/periarteritis is a recently identified disease entity in IgG4-RD that affects the cardiovascular system. Since the genetic factors related to disease onset are unclear, we examined the genetic associations with IgG4-related periaortitis/periarteritis susceptibility. METHODS: A small scale of genome-wide association analysis identified that interleukin 1 receptor type 1 (IL1R1) gene variants were correlated with the development of IgG4-related periaortitis/periarteritis in 75 patients with IgG4-RD. Accordingly, 8 single nucleotide polymorphisms (SNPs) in the IL1R1 gene were selected and genotyped in 124 patients with IgG4-RD (43 with periaortitis/periarteritis and 81 without periaortitis/periarteritis) and 344 healthy subjects. RESULTS: The minor allele frequencies of 6 SNPs (rs2287049, rs3917273, rs2160227, rs951192, rs3917318, rs7582198) were significantly increased in IgG4-related periaortitis/periarteritis patients compared with those without periaortitis/periarteritis (corrected P < 0.05). In addition, the frequency of the AGAAA haplotype, comprised of 5 SNPs (rs3917273, rs2160227, rs951192, rs3917318, rs7582198), was significantly higher in patients with periaortitis/periarteritis (OR = 2.41, 95% CI:1.42-4.10). CONCLUSION: Our findings indicated that IL1R1 genetic polymorphisms contributed to IgG4-related periaortitis/periarteritis and the possibility of certain genetic factors influencing the risk of specific IgG4-RD manifestations.

Does the Interaction of KIR and HLA Affect the Development of Non-Infectious Uveitis?

Immune tolerance is established in the eye to prevent permanent blindness associated with destructive damage to the cornea and retina caused by immune cell infiltration; hence, the immune responses and subsequent inflammations are strongly suppressed. While non-infectious uveitis develops from a disruption of immune tolerance in the eye, its onset is a result of accumulating etiologic factors, including genetic predisposition, environmental factors, and aging. Many non-infectious uveitis cases are genetically predisposed to human leukocyte antigen (HLA) as the most substantial disease susceptibility region. HLA class I molecules are critical for natural killer (NK) cells to distinguish between self and non-self. The killer cell Ig-like receptor (KIR) family is one of the essential components of these receptors. Evidence has accumulated that NK cells are involved in innate and acquired immunity by interacting with other immunocompetent cells to develop several autoimmune diseases. This review summarizes the possible role of KIR in the development of non-infectious uveitis.

Association analysis of KIR/HLA genotype with liver cirrhosis, hepatocellular carcinoma, and NUC freedom in chronic hepatitis B patients.

Natural killer cells are modulated through the binding of killer cell immunoglobulin-like receptors (KIRs) with human leukocyte antigen (HLA) class I ligands. This study investigated the association of KIR/HLA pairs with progression to liver cirrhosis, hepatocellular carcinoma (HCC) development, and nucleot(s)ide (NUC) treatment freedom in hepatitis B virus (HBV) infection. KIR, HLA-Bw, and HLA-C were genotyped in 280 Japanese HBV patients for clinical comparisons. No significant associations of KIR/HLA pairs were detected in terms of liver cirrhosis development. The KIR2DS3 positive rate was significantly higher in patients with HCC (n = 39) than in those without (n = 241) [30.8% vs. 14.9%, odds ratio (OR) 2.53, P = 0.015]. The KIR3DL1/HLA-Bw4 pair rate was significantly lower in the NUC freedom group (n = 20) than in the NUC continue group (n = 114) (25.0% vs. 52.6%, OR 0.30, P = 0.042). In conclusion, this study indicated remarkable associations of KIR/HLA with HCC development (KIR2DS3) and freedom from NUC therapy (KIR3DL1/HLA-Bw4) in HBV patients, although the number of cases was insufficient for statistical purposes. Additional multi-center analyses of larger groups are needed to clarify whether KIR/HLA pairs play a role in HBV patient status.

Protocol: Prospective observational study aiming for micro-elimination of hepatitis C virus in Nagawa town: The Nagawa Project.

BACKGROUND: The World Health Organization has set a goal of hepatitis C virus (HCV) elimination by the year 2030. However, no regions in Japan have succeeded in eradicating HCV. Micro-elimination is an approach to attain hepatitis C eradication in which national eradication goals are applied to specific populations so that viral treatment and control efforts can move forward quickly and efficiently. In order to eradicate HCV from Japan, this study aims to achieve HCV micro-elimination in the town of Nagawa. METHODS AND DESIGN: The Nagawa Project is an ongoing, prospective, multiple-institution, observational study running from April 1, 2021, to March 31, 2024. All residents of Nagawa town, excluding those under 20 years of age, not consenting to the study, or unable to undergo health check-ups due to nursing care needs, will be included. If found to be HCV antibody-positive, the participant will be recommended to see a doctor in consideration of MAC-2 binding protein glycosylation isomer values. Then, the participant will undergo serum HCV RNA measurement with the real-time polymerase chain reaction by an attending physician. If the participant is HCV RNA-positive, he or she will be referred to a hepatologist for further evaluation. In the case of a definitive diagnosis of chronic hepatitis C, direct acting antiviral treatment will be initiated. Through this process, HCV will be systematically micro-eliminated from the region. DISCUSSION: The Nagawa Project will reveal the prevalence of chronic HCV in addition to the HCV eradication rate in Nagawa town towards achieving HCV micro-elimination. TRIAL REGISTRATION: This study is performed by Shinshu University School of Medicine and was registered as UMIN 000044114 on May 6, 2021.

Investigation of the Effect of KIR-HLA Pairs on Hepatocellular Carcinoma in Hepatitis C Virus Cirrhotic Patients.

Natural killer cells are partially mediated through the binding of killer cell immunoglobulin-like receptors (KIR) with human leukocyte antigen (HLA) class I ligands. This investigation examined the risk of hepatocellular carcinoma (HCC) in relation to KIR-HLA pairs in patients with compensated hepatitis C virus (HCV)-associated cirrhosis. A total of 211 Japanese compensated HCV cirrhotic cases were retrospectively enrolled. After KIR, HLA-A, HLA-Bw, and HLA-C typing, associations between HLA, KIR, and KIR-HLA combinations and HCC development were evaluated using the Cox proportional hazards model with the stepwise method. During a median follow-up period of 6.6 years, 69.7% of patients exhibited HCC. The proportions of HLA-Bw4 and the KIR3DL1 + HLA-Bw4 pair were significantly higher in patients with HCC than in those without (78.9% vs. 64.1%; odds ratio (OR)-2.10, 95% confidence interval (CI)-1.10-4.01; p = 0.023 and 76.2% vs. 60.9%, odds ratio-2.05, p = 0.024, respectively). Multivariate analysis revealed the factors of male gender (hazard ratio (HR)-1.56, 95% CI-1.12-2.17; p = 0.009), α-fetoprotein > 5.6 ng/mL (HR-1.56, 95% CI-1.10-2.10; p = 0.011), and KIR3DL1 + HLA-Bw4 (HR-1.69, 95% CI-1.15-2.48; p = 0.007) as independent risk factors for developing HCC. Furthermore, the cumulative incidence of HCC was significantly higher in patients with KIR3DL1 + HLA-Bw4 than in those without (log-rank test; p = 0.013). The above findings suggest KIR3DL1 + HLA-Bw4, in addition to HLA-Bw4, as a novel KIR-HLA pair possibly associated with HCC development in HCV cirrhosis. HCV-associated cirrhotic patients with the risk factors of male gender, α-fetoprotein > 5.6 ng/mL, and KIR3DL1 + HLA-Bw4 may require careful surveillance for HCC onset.

Quantitative and qualitative lipid improvement with chronic hepatitis C virus eradication using direct-acting antivirals.

AIM: Direct-acting antivirals have revolutionized hepatitis C virus (HCV) therapy by providing a high sustained virological response (SVR) rate and subsequent favorable lipid increases. Proprotein convertase subtilisin-kexin like-9 (PCSK9) plays an important role in regulating quantitative lipid levels. This study examined the interactions between quantitative PCSK9 and lipid changes, as well as qualitative lipid changes in terms of lectin-like oxidized low-density lipoprotein (LDL) receptor-1 ligand containing apolipoprotein B (LAB) and high-density lipoprotein (HDL) cholesterol uptake capacity (HDL-CUC). METHODS: Patients with chronic HCV infection (N = 231) who achieved an SVR by direct-acting antivirals without lipid-lowering therapy were included for comparisons of PCSK9, LAB, HDL-CUC, and other clinical indices between pretreatment and SVR12 time points. RESULTS: LDL (LDL) cholesterol and HDL cholesterol levels were quantitatively increased at SVR12, along with higher PCSK9 (all p < 0.0001). PCSK9 was significantly correlated with LDL cholesterol (r = 0.244, p = 0.0003) and apolipoprotein B (r = 0.222, p = 0.0009) at SVR12. Regarding qualitative LDL changes, LAB was significantly decreased and LAB/LDL cholesterol and LAB/apolipoprotein B proportions were improved at SVR12 (all p < 0.0001). In terms of qualitative HDL changes, HDL-CUC was significantly ameliorated, along with HDL-CUC/HDL cholesterol, HDL-CUC/ apolipoprotein A1, and HDL-CUC/ apolipoprotein A2 at SVR12 (all p < 0.0001). CONCLUSIONS: HCV eradication by direct-acting antivirals may produce quantitative lipid profile changes, along with PCSK9 production recovery in addition to qualitative lipid improvement, which possibly confers the additional secondary benefits of atherosclerosis improvement and cardiovascular disease event reduction.

Genetic control of CCL24, POR, and IL23R contributes to the pathogenesis of sarcoidosis.

Sarcoidosis is a genetically complex systemic inflammatory disease that affects multiple organs. We present a GWAS of a Japanese cohort (700 sarcoidosis cases and 886 controls) with replication in independent samples from Japan (931 cases and 1,042 controls) and the Czech Republic (265 cases and 264 controls). We identified three loci outside the HLA complex, CCL24, STYXL1-SRRM3, and C1orf141-IL23R, which showed genome-wide significant associations (P < 5.0 × 10-8) with sarcoidosis; CCL24 and STYXL1-SRRM3 were novel. The disease-risk alleles in CCL24 and IL23R were associated with reduced CCL24 and IL23R expression, respectively. The disease-risk allele in STYXL1-SRRM3 was associated with elevated POR expression. These results suggest that genetic control of CCL24, POR, and IL23R expression contribute to the pathogenesis of sarcoidosis. We speculate that the CCL24 risk allele might be involved in a polarized Th1 response in sarcoidosis, and that POR and IL23R risk alleles may lead to diminished host defense against sarcoidosis pathogens.

The Gly82Ser mutation in AGER contributes to pathogenesis of pulmonary fibrosis in combined pulmonary fibrosis and emphysema (CPFE) in Japanese patients.

The dominant pathogenesis underlying the combined pulmonary fibrosis and emphysema (CPFE) remains unresolved. The receptor for advanced glycation end-products (RAGE) is highly expressed in lung tissues and interacts with distinct multiple ligands, implicating it in certain lung diseases. To elucidate the pathogenesis of CPFE, we genotyped three single nucleotide polymorphisms (SNPs: rs2070600, rs1800625, and rs2853807) of the gene encoding RAGE (AGER) in 111 CPFE patients and 337 chronic obstructive pulmonary disease (COPD) patients of Japanese by using StepOne Real-Time PCR System for SNP genotyping assay. Serum levels of soluble RAGE (sRAGE) were measured by ELISA. We found that the allele frequency of rs2070600 was significantly different between the two groups [corrected P (Pc) = 0.015]. In addition, the minor allele was associated with CPFE patients relative to COPD patients in a dominant effect model (Odds Ratio = 1.93; Pc = 0.018). Moreover, the serum sRAGE level was significantly lower in the CPFE group than the COPD group (P = 0.014). The rs2070600 minor allele was significantly associated with reduced sRAGE level in CPFE patients and independently affected sRAGE level reduction in this group (P = 0.020). We concluded that the AGER rs2070600 minor allele (Gly82Ser mutation) is associated with the pathogenesis of pulmonary fibrosis in CPFE in Japanese patients.

Polymorphism at rs9264942 is associated with HLA-C expression and inflammatory bowel disease in the Japanese.

An expression quantitative trait locus (eQTL) single-nucleotide polymorphism (SNP) at rs9264942 was earlier associated with human leukocyte antigen (HLA)-C expression in Europeans. HLA-C has also been related to inflammatory bowel disease (IBD) risk in the Japanese. This study examined whether an eQTL SNP at rs9264942 could regulate HLA-C expression and whether four SNP haplotypes, including the eQTL SNP at rs9264942 and three SNPs at rs2270191, rs3132550, and rs6915986 of IBD risk carried in the HLA-C*12:02~B*52:01~DRB1*15:02 allele, were associated with IBD in the Japanese. HLA-C expression on CD3e+CD8a+ lymphocytes was significantly higher for the CC or CT genotype than for the TT genotype of rs9264942. The TACC haplotype of the four SNPs was associated with a strong susceptibility to ulcerative colitis (UC) but protection against Crohn's disease (CD) as well as with disease clinical outcome. While UC protectivity was significant but CD susceptibility was not for the CGTT haplotype, the significance of UC protectivity disappeared but CD susceptibility reached significance for the CGCT haplotype. In conclusion, our findings support that the eQTL SNP at rs9264942 regulates HLA-C expression in the Japanese and suggest that the four SNPs, which are in strong linkage disequilibrium, may be surrogate marker candidates of a particular HLA haplotype, HLA-C*12:02~B*52:01~DRB1*15:02, related to IBD susceptibility and disease outcome.

Genome-Wide Association Study in Asians Identifies Novel Loci for High Myopia and Highlights a Nervous System Role in Its Pathogenesis.

PURPOSE: To identify novel susceptibility loci for high myopia. DESIGN: Genome-wide association study (GWAS) followed by replication and meta-analysis. PARTICIPANTS: A total of 14 096 samples from East and Southeast Asian populations (2549 patients with high myopia and 11 547 healthy controls). METHODS: We performed a GWAS in 3269 Japanese individuals (1668 with high myopia and 1601 control participants), followed by replication analysis in a total of 10 827 additional samples (881 with high myopia and 9946 control participants) from Japan, Singapore, and Taiwan. To confirm the biological role of the identified loci in the pathogenesis of high myopia, we performed functional annotation and Gene Ontology (GO) analyses. MAIN OUTCOME MEASURES: We evaluated the association of single nucleotide polymorphisms with high myopia and GO terms enriched among genes identified in the current study. RESULTS: We identified 9 loci with genome-wide significance (P < 5.0 × 10-8). Three loci were previously reported myopia-related loci (ZC3H11B on 1q41, GJD2 on 15q14, and RASGRF1 on 15q25.1), and the other 6 were novel (HIVEP3 on 1p34.2, NFASC/CNTN2 on 1q32.1, CNTN4/CNTN6 on 3p26.3, FRMD4B on 3p14.1, LINC02418 on 12q24.33, and AKAP13 on 15q25.3). The GO analysis revealed a significant role of the nervous system related to synaptic signaling, neuronal development, and Ras/Rho signaling in the pathogenesis of high myopia. CONCLUSIONS: The current study identified 6 novel loci associated with high myopia and demonstrated an important role of the nervous system in the disease pathogenesis. Our findings give new insight into the genetic factors underlying myopia, including high myopia, by connecting previous findings and allowing for a clarified interpretation of the cause and pathophysiologic features of myopia at the molecular level.

Variants in IL23R-C1orf141 and ADO-ZNF365-EGR2 are associated with susceptibility to Vogt-Koyanagi-Harada disease in Japanese population.

Vogt-Koyanagi-Harada (VKH) disease is a systemic inflammatory disorder that affects pigment cell-containing organs such as the eye (e.g., chronic and/or recurrent granulomatous panuveitis). While the exact etiology and pathogenic mechanism of VKH disease are unclear, HLA-DR4 alleles have been documented to be strongly associated with VKH disease in various ethnic groups. Recently, a genome-wide association study (GWAS) found two new genetic risk factors (IL23R-C1orf141 and ADO-ZNF365-EGR2) in a non-HLA region from a Han Chinese population. In this study, we replicated these GWAS findings in a Japanese population. A total of 1,643 Japanese samples (380 cases with VKH disease and 1,263 healthy controls) were recruited. We assessed four single nucleotide polymorphisms (SNPs) shown in previous GWAS: rs78377598 and rs117633859 in IL23R-C1orf141, and rs442309 and rs224058 in ADO-ZNF365-EGR2. A significant allelic association with VKH disease was observed for all of the four SNPs (rs78377598: pc = 0.0057; rs117633859: pc = 0.0017; rs442309: pc = 0.021; rs224058: pc = 0.035). In genotypic association analysis, the minor alleles of IL23R-C1orf141 rs78377598 and rs117633859 had the strongest association with disease susceptibility under the additive model (pc = 0.0075 and pc = 0.0026, respectively). The minor alleles of ADO-ZNF365-EGR2 rs442309 and rs224058 were most strongly associated with disease susceptibility under the dominant model (pc = 0.00099 and pc = 0.0023, respectively). The meta-analysis of the current and previous studies found that all of the four SNPs exhibited a significantly strong association with VKH disease (meta-p < 0.00001: rs78377598, meta-odds ratio (OR) = 1.69; rs1176338, meta-OR = 1.82; rs442309, meta-OR = 1.34; rs224058, meta-OR = 1.33). In summary, our study replicated significant associations with VKH disease susceptibility reported in a previous GWAS. Thus, the IL23R-C1orf141 and ADO-ZNF365-EGR2 loci may play important roles in the development of VKH disease through genetic polymorphisms.

Association of HLA-DRB1*04:05 allele with drug-induced interstitial lung disease in Japanese population.

Drug-induced interstitial lung disease (DILD) is a life-threatening adverse reaction. The Japanese population is more susceptible to DILD as compared with other populations, suggesting its pathogenesis could vary depending on ethnic genetic background. We conducted case-control studies to elucidate the association between DILD and HLA alleles in the Japanese. The 177 clinically diagnosed DILD patients and 3002 healthy controls for exploration and 55 DILD patients and 201 healthy controls for validation were genotyped for four HLA genes. HLA-DRB1*04:05 was significantly associated with DILD (corrected p = 0.014); this was also validated in the other set of patients/controls. Chemical drugs other than protein therapeutics showed this association (p = 1.7 × 10-4) . The Japanese population showed a higher HLA-DRB1*04:05 frequency than most other populations. In conclusion, HLA-DRB1*04:05 could be associated with DILD susceptibility in Japanese individuals, and its high general frequency may explain the high reported incidence of DILD in Japanese.