Rare germline variants in pancreatic cancer and multiple primary cancers: an autopsy study.

BACKGROUND: There is a lack of information on rare germline variants of pancreatic cancer-predisposing genes. Risk genes for multiple primary cancers may overlap with those for pancreatic cancer. METHODS: A retrospective study of autopsy cases with a negative family history in the Japanese single nucleotide polymorphism for geriatric research database examined rare germline variants in the protein-coding regions of 61 genes. Targeted sequencing of these genes was performed and classified for pathogenicity using the American College of Medical Genetics and Genomics guidelines. Polyphen-2, SIFT and LoFtool algorithms were used to predict damage to protein function. RESULTS: Of the 189 subjects used (90 cancer and 99 non-cancer controls), 72 patients had pancreatic cancer (23 had multiple primary cancers) and 18 had no pancreatic cancer in multiple primary cancers. APC, BRCA2, BUB1B, ENG and MSH6 were associated with cancer predisposition, and pathogenic/likely pathogenic (P/LP) variants occurred in 6% [pancreatic cancer (4/72); all-cancer (5/90)] and 54% (49/90) carried only variants of uncertain significance (VUS) among cancer patients. Of these VUS, in pancreatic cancer patients, four DNA mismatch repair (MMR) genes ( MLH1, MSH2, MSH6 and PMS2 ), and POLQ in men were significantly associated (odds ratio = 3.83; P = 0.025; P = 0.027, respectively). The most abundant predictor of functionally damaging variants was POLQ . CONCLUSIONS: The frequency of P/LP variants in patients with sporadic pancreatic cancer suggests the need for genetic evaluation of individuals with no family history. VUS of MMR genes ( MLH1, MSH2, MSH6 and PMS2 ) and POLQ may be useful in predicting genetic trends in the potential risk of pancreatic cancer, especially in individuals lacking P/LP.

Estrogen Receptor-ß Gene Cytosine-Adenine (ESR2-CA) Repeat Polymorphism in Postmenopausal Colon Cancer.

The pathobiological role of estrogen is controversial in colorectal cancer. Cytosine-adenine (CA) repeat in the estrogen receptor (ER)-ß gene (ESR2-CA) is a microsatellite, as well as representative of ESR2 polymorphism. Though its function is unknown, we previously showed that a shorter allele (germline) increased the risk of colon cancer in older women, whereas it decreased it in younger postmenopausal women. ESR2-CA and ER-ß expressions were examined in cancerous (Ca) and non-cancerous (NonCa) tissue pairs from 114 postmenopausal women, and comparisons were made considering tissue types, age/locus, and the mismatch repair protein (MMR) status. ESR2-CA repeats <22/≥22 were designated as 'S'/'L', respectively, resulting in genotypes SS/nSS (=SL&LL). In NonCa, the rate of the SS genotype and ER-ß expression level were significantly higher in right-sided cases of women ≥70 (≥70Rt) than in those in the others. A decreased ER-ß expression in Ca compared with NonCa was observed in proficient-MMR, but not in deficient-MMR. In NonCa, but not in Ca, ER-ß expression was significantly higher in SS than in nSS. ≥70Rt cases were characterized by NonCa with a high rate of SS genotype or high ER-ß expression. The germline ESR2-CA genotype and resulting ER-ß expression were considered to affect the clinical characteristics (age/locus/MMR status) of colon cancer, supporting our previous findings.

Sub-GOFA: A tool for Sub-Gene Ontology function analysis in clonal mosaicism using semantic (logical) similarity.

Clonal mosaicism (a detectable post-zygotic mutational event in cellular subpopulations) is common in cancer patients. Detected segments of clonal mosaicism are usually bundled into large-locus regions for statistical analysis. However, low-frequency genes are overlooked and are not sufficient to elucidate qualitative differences between cancer patients and non-patients. Therefore, it is of interest to develop and describe a tool named Sub-GOFA for Sub-Gene Ontology function analysis in clonal mosaicism using semantic similarity. Sub-GOFA measures the semantic (logical) similarity among patients using the sub-GO network structures of various sizes segmented from the gene ontology (GO) for clustering analysis. The sub-GO's root-terms with significant differences are extracted as disease-associated genetic functions. Sub-GOFA selected a high ratio of cancer-associated genes under validation with acceptable threshold.

COL17A1 germline variant p.Ser1029Ala and mucosal malignant melanoma: An autopsy study.

Collagen type XVII α1 (COL17A1) encodes a hemidesmosomal protein at the epidermal-dermal junction and its variants are implicated in blistering skin diseases. Recent experiments in rodents revealed that Col17a1 has critical roles in stem cells of epidermal origin and in melanoma carcinogenesis. In the present study, it was investigated whether germline variants in COL17A1 are associated with skin cancer and other cancer types using indexed consecutive autopsy cases from the Japanese Geriatric Single Nucleotide Polymorphism database (n=2,343; mean age, 80 years). The database included 12 patients with skin cancer. A total of 53 COL17A1 missense variants on an exome chip were analyzed. One variant, p.Ser1029Ala (rs118166857), which had a minor allele frequency of 1.0%, exhibited a nominal positive sign of association with skin cancer [Fisher's exact P=0.002, odds ratio (OR)=16.93, 95% CI: 4.44-64.64]. This variant was detected in 2/2 patients with mucosal malignant melanoma (mMM) and 1/3 patients with extramammary Paget's disease, and in none of the patients with non-melanoma cancer, e.g., squamous cell and basal cell carcinoma. Other cancer types were searched in the database and the p.Ser1029Ala variant was indicated to be nominally associated with breast cancer (P=0.006, OR=4.17, 95% CI: 1.72-10.11). In the two mMM cases, targeted exome sequencing of 55 cancer-predisposing genes (including tumor protein 53, BRCA1/2 and mismatch repair genes) detected no apparent pathogenic variants, but revealed variants of unknown significance in axin 2, DNA directed polymerase ζ catalytic subunit and contactin 6. Since COL17A1 provides a niche for melanocyte stem cells, it was hypothesized that the p.Ser1029Ala variant in the COL17A1 ectodomain may affect the microenvironment, e.g., the cell competition. This is a working hypothesis generated from human autopsy cases and warrants further epidemiological and molecular biological validation.

Trimester-specific associations between extracellular vesicle microRNAs and fetal growth.

OBJECTIVE: Placenta-derived extracellular vesicles and their cargoes, especially microRNAs (EV-miRNAs), may contribute to fetal and placental development. During pregnancy, the levels of several maternal blood EV-miRNAs, including miRNAs of placental origin, vary among individuals and change throughout gestation. However, the effects of these miRNAs on fetal growth and trimester-specificity have not been fully elucidated. The purpose of this study is to test the hypothesis that the serum levels of two extracellular vesicles (EV)-miRNAs (miR-127-3p and miR-26b-5p), which may be involved in fetoplacental regulation, would be significantly associated with fetal growth in a trimester-specific manner. MATERIALS AND METHODS: This is a single-center birth cohort of maternal serum samples obtained at both the second and third trimesters. To minimize the influence of confounding factors, the analysis was limited to singleton vaginal deliveries, resulting in 27 participants being included in this study. EV RNAs were isolated using a membrane affinity method, and the relative expression levels of miR-127-3p and miR-26b-5p were measured using the RT-qPCR method with miR-484 as control. The associations between the two EV-miRNAs and fetal and placental growth were evaluated using a linear regression model and compared between the two trimesters. RESULTS: EV-miR-127-3p levels tended to correlate inversely with the z-scores of birth weight for gestational age (BWGA) and placental weight for gestational age (PWGA) in the second trimester, but not in the third trimester. EV-miR-26b-5p levels were positively associated with birth weight in the second trimester, but this association was weakened in the third trimester. CONCLUSION: Our results suggest a trimester-specific association of circulating miRNA levels with fetal and placental growth. The precise roles of EV-miR-127-3p and EV-miR-26b-5p in fetal and placental development warrant further investigation.

D-amino acid oxidase (DAO) rare genetic missense variant p.Pro103Leu and gastric cancer.

Gastric cancer is prevalent in the Asian population. Genetic predisposition to gastric cancer is not fully understood. Recent studies have demonstrated that D-amino acid oxidase (DAO), a multifunctional enzyme, protects the mucosa of gastrointestinal (GI) tracts by generating hydrogen sulfide (H2S) in the stomach of rodents. The present study surveyed rare germline variants in the human DAO gene with regard to the incidence of gastric cancer. The consecutive autopsy cases registered in the JG-SNP database (n=2,343; mean age, 80 years) were employed and genotyped with Exome Bead-Chips. There were three non-synonymous rare variants, p.R22H, p.P103L and p.R283Q, of which the minor allele frequencies were 0.09, 0.21 and 0.02%, respectively. Carriers of these variants were surveyed, the results of which revealed that 4 out of 10 patients with the p.P103L variant had gastric cancer (Fisher's exact test, P=0.018). All 4 patients were men with drinking and smoking habits. Among the other 6 women, there was one incidence of small intestine cancer and one of colon cancer. Neither p.R22H nor p.R283Q carriers had GI cancer. DAO p.P103L is reported to be a modifier of amyotrophic lateral sclerosis (ALS) and may potentially be a hypomorphic allele. Thus, it is hypothesized that this rare variant might have affected protection against gastric mucosal damage through H2S signaling in the mucosa, which leads to high prevalence of gastric cancer. The role of rare variant DAO p.P103L warrants further investigation in larger cohorts.

Single nucleotide polymorphisms in tinnitus patients exhibiting severe distress.

The association between distress caused by tinnitus and psychological factors such as depression and anxiety has been examined and reported. However, prognostic factors remain poorly understood because there are only a few reports on genetic associations. We theorized there might be an association between the grade of tinnitus distress and the genetic background related to psychological factors which might lead us to identify prognostic markers. We enrolled 138 patients who had suffered from tinnitus for over 3 months. Using Tinnitus Handicap Inventory (THI) scores, we examined the association between tinnitus distress and a genetic background related to depression or anxiety. A significant association between single nucleotide polymorphism rs131702 of the Breakpoint Cluster Region (BCR) gene and the severe THI score was identified. In addition, there was an association with the severity of the State-Trait Anxiety Inventory, an index of state anxiety severity. No association was found with the Self-Rating Depression Scale, an index of depression severity. It is reported that rs131702 of BCR in Japanese patients are related to bipolar II depression characterized by fluctuation between abnormal mood states of mania and depression. Our results indicate that rs131702 of BCR is independent of depression in this study and is, therefore, a prognostic factor unique to tinnitus. We conclude that the severity of tinnitus is associated with genes related to depression.

Association between rs1229984 in ADH1B and cancer prevalence in a Japanese population.

Alcohol consumption is an established risk factor for cancer, but little is known regarding the effect of genetic polymorphisms in alcohol metabolism genes on alcohol-related cancer risk in the Japanese population. Associations between the ADH1B gene (alcohol dehydrogenase 1B), single nucleotide polymorphism (SNP) rs1229984 and cancer have been extensively studied yet evidence is inconsistent. This population-based case-control study primarily aimed to clarify any association between SNP rs1229984 in both overall and specific cancer risk in a Japanese population. The functional non-synonymous SNP rs1229984 (Arg48His) was genotyped using DNA samples from 1,359 consecutive autopsy cases registered in The Japanese Single Nucleotide Polymorphisms for Geriatric Research database. Medical and pathological record data from this database were used to categorise cases and controls. Results included 1,359 participants, 816 cases and 543 controls. Multinomial logistic regression analyses showed no significant association between rs1229984 presence and overall cancer risk in both dominant and recessive genetic inheritance models [Arg/Arg+Arg/His vs. His/His: Adjusted odds ratio (OR)=0.66 (95% CI=0.39-1.13; P=0.129), Arg/Arg vs. Arg/His+His/His: OR=0.95 (95% CI=0.75-1.20; P=0.657)]. However, results showed those homozygous for rs1229984 (genotype His/His) were at significantly decreased odds of lung cancer than other genotypes [recessive model: OR=0.64 (95% CI=0.44-0.93; P=0.020]. In conclusion, there was no significant association between rs1229984 and odds of overall or specific cancers except in lung cancer where His/His genotype decreased odds. To the best of our knowledge, the association between His/His and decreased odds of lung cancer is a novel finding. These findings require further validation in larger studies.

Association of CYP2A6 gene deletion with cancers in Japanese elderly: an autopsy study.

BACKGROUND: CYP2A6 is an enzyme involved in oxidation of a number of environmental chemicals, including nicotine, pro-carcinogenic nitrosamines and polycyclic aromatic hydrocarbons (PAHs). The whole gene deletion of CYP2A6 (CYP2A6*4) is prevalent in East Asian population. Whether or not CYP2A6*4 associates with cancer is still controversial. METHODS: We undertook an association study to determine whether deletion of CYP2A6 gene associates with total cancer and major cancer types employing data of consecutive autopsy cases registered in the Japanese single-nucleotide polymorphisms for geriatric research (JG-SNP) database. The presence of cancer were inspected at the time of autopsy and pathologically confirmed. Genotyping for CYP2A6 wild type (W) and deletion (D) was done by allele specific RT-PCR method. RESULTS: Among 1373 subjects, 826 subjects (60.2%) were cancer positive and 547 subjects (39.8%) were cancer negative. The genotype frequency in the whole study group for WW, WD and DD were 65.0, 30.6 and 4.4%, respectively, which obeyed the Hardy-Weinberg equilibrium (p = 0.20). Total cancer presence, as well as major cancers including gastric, lung, colorectal, and blood cancers did not show any positive association with CYP2A6 deletion. When male and female were separately analyzed, CYP2A6 deletion associated with decreased gastric cancer risk in female (OR = 0.49, 95%CI: 0.25-0.95, p = 0.021, after adjustment for age, smoking and drinking). When smoker and non-smoker were separately analyzed, CYP2A6 deletion associated with decreased total cancer in female nonsmokers (OR = 0.67, 95%CI: 0.45-0.99, p = 0.041 after adjustment). On the other hand, CYP2A6 deletion associated increase blood cancers in smokers (OR = 2.05, 95%CI: 1.19-3.53, p = 0.01 after adjustment). CONCLUSION: The CYP2A6 deletion may not grossly affect total cancer. It may associate with individual cancers in sex and smoking dependent manner. Further studies with larger sample size are warranted to confirm our results.

Association study of long non-coding RNA HOTAIR rs920778 polymorphism with the risk of cancer in an elderly Japanese population.

The HOTAIR gene encodes a long noncoding RNA (lncRNA), which functions in development and tumorigenesis. A single nucleotide polymorphism (SNP) rs920778 in the HOTAIR gene, has been recurrently studied for susceptibility to many cancers including oesophageal cancer, gastric cancer, lung cancer, and hepatocellular carcinoma. Most of these studies were conducted in Chinese populations, and a few in Turkish, Iranian, and Portuguese populations. They mostly give rise to controversial results. It still remains largely unknown whether the cancer risk is conferred in a Japanese population. Here, we established an association study on the representative SNP rs920778, to examine its contribution to the presence of cancer in consecutive autopsy cases in the JG-SNP database. A total of 1373 subjects (mean age 80) including 827 cancer positive and 546 cancer negative subjects were analyzed. As a result, the occurrence of overall cancer was not associated with the rs920778 polymorphism (p > 0.05). For each cancer type, we did not find association except for lung cancer (p = 0.04) which was more likely a by-chance association after multiple testing. Our findings imply that rs920778 polymorphism does not affect total cancer presence and the effect on specific cancer types is also weak in the Japanese population.

Clinicopathological characteristics of gastric cancer with carbohydrate antigen 19-9 expression occurring in elderly individuals: An autopsy study.

The clinicopathological significance of carbohydrate antigen 19-9 (CA19-9) in gastric cancer (GC) remains obscure. Therefore, the current study aimed to clarify the clinicopathological value of CA19-9 in GC utilizing autopsy cases. We examined the expression of CA19-9 and mucin core proteins in GC immunohistochemically, and analyzed serum CA19-9 levels and clinicopathological variables or complications. We also investigated whether fucosyltransferases 2 and 3 (FUT2/3) allelic variants influence CA19-9 expression in GC. Compared to GC cases with negative CA19-9 expression (tCA19-9-N), those with positive CA19-9 expression (tCA19-9-P) demonstrated significant differences in characteristic features such as lymph node and distant organ metastases, lymphatic and venous permeation, and higher Tumor, Node, Metastasis (TNM) stages. Moreover, compared to GC cases with low serum CA19-9 levels (sCA19-9-L), those with high serum CA19-9 levels (sCA19-9-H) were related to venous permeation, higher proportion of lymph node and distant organ metastases, and higher TNM stages. Both tCA19-9-P GC and sCA19-9-H GC cases were significantly associated with coagulation abnormalities. sCA19-9-H GC cases correlated significantly with MUC1 and MUC5AC expression. FUT2/3 genotypes were not associated with CA19-9 expression in GC. These results suggest that CA19-9 can predict the risk of lymph node and distant metastases as well as of coagulation abnormalities.

The stem cell-specific intermediate filament nestin missense variation p.A1199P is associated with pancreatic cancer.

The intermediate filament nestin is upregulated in stem/progenitor cells and cancers, and regulates cell proliferation, migration, invasion and stemness. The present study comparatively analyzed serial autopsies of Japanese patients (n=2,206; males, 1,225; females, 981; median, 80.7 years old; range, 33-104 years old) with malignant tumors of whole organs, with respect to the clinical information, and 5 single nucleotide polymorphisms of the nestin gene. p.A1199P associated with pancreatic cancer (odds ratio, 4.4; 95% confidence interval, 1.9-10.0, P=0.001) while it did not associate with malignant neoplasms in other organs. p.A1199P did not associate with precancerous lesions of the pancreas. Single nucleotide polymorphisms of nestin were not associated with sex, drinking, smoking, or body weight. In conclusion, the amino acid 1,199 of nestin is localized in the tail structure of the filament and polymerizes with other intermediate filament proteins. The present results suggest that missense variations of nestin affect pancreatic carcinogenesis in Japanese patients.

Self-organizing scale-free patterns in a phase-modulated periodic connecting system.

OBJECTIVE: The regularity of scale-free patterns in rank-size relations has been observed in word frequency, city size distribution, firm size distribution, and gene expression. Because of the common emergence of this regularity, understanding its mechanisms has been of great interest. For obtaining the scale-free pattern regularity, various models based on the rich-get-richer mechanism have been proposed; however, the overarching procedure of searching for the "rich" is in disagreement with the locally interacting behaviors seen in the aforementioned natural and social phenomena. RESULTS: We implemented a computational model of a resource distribution system inspired by observations of word connectivity, which is created by local constraints with periodic and phase modulatory features. Here, we empirically demonstrated that a phase-modulated periodic connecting system can reach a dynamic equilibrium state as the most probable case, with the self-organizing scale-free patterns. The regularity could be a result of the configurational balance in spatiotemporal inequity during the resource distribution process with an adaptive constrained connectivity. Our results suggest that investigations of interferences of oscillating fluctuations in the system will elucidate the autoregulatory dynamic behavior.

Metabolic and Immunological Shifts during Mid-to-Late Gestation Influence Maternal Blood Methylation of CPT1A and SREBF1.

Mid-to-late gestation is a unique period in which women experience dynamic changes in lipid metabolism. Although the recent intensive epigenome-wide association studies (EWAS) using peripheral leukocytes have revealed that lipid-related traits alter DNA methylation, the influence of pregnancy-induced metabolic changes on the methylation levels of these differentially methylated sites is not well known. In this study, we performed a prospective cohort study of pregnant women (n = 52) using the MassARRAY EpiTYPER assay and analyzed the methylation levels of variably methylated sites, including CPT1A intron 1 and SREBF1 intron 1 CpGs, which were previously verified to be robustly associated with adiposity traits. Although methylation of SREBF1 was associated with body mass index (BMI) and low-density lipoprotein cholesterol at mid-gestation, this association was attenuated at late gestation, which was consistent with the metabolic switch from an anabolic to a catabolic state. However, the BMI association with CPT1A intron 1 methylation appeared to strengthen at late gestation; this association was mediated by pre-pregnancy BMI-dependent change in the leukocyte proportion during mid-to-late gestation. Thus, the methylation of adiposity-related differentially methylated regions was sensitive to metabolic and immunological changes during mid-to-late gestation.

Effectiveness of personal genomic testing for disease-prevention behavior when combined with careful consultation with a physician: a preliminary study.

OBJECTIVES: There are many direct-to-consumer (DTC)-type personal genomic testing (PGT) services commercially available to the public, providing the specific disease susceptibilities of individuals. While these services do not appear to stimulate disease-prevention behavior, few studies have addressed the methods to do so. We investigated the effectiveness of combining a consultation with a physician with the delivery of test results from a DTC-type PGT, as a preliminary study to identify the effective genomic testing for disease-prevention. A prepared physician disclosed the PGT results of twenty healthy subjects and provided a specific consultation on the high-risk diseases for each subject. The effects on the sense of health, understanding of possible future diseases, and preventive behaviors for each subject were examined pre-PGT, post-PGT, and 3, 6, and 12 months post-PGT. RESULTS: Significant increases between the pre- and post-PGT scores were observed for the awareness of lifestyle effects on developing those diseases (P < 0.05) and the awareness of the ability to influence disease onset (P < 0.01). The follow-up questionnaire results showed that over 60% of the subjects changed their lifestyles in favor of disease prevention. These results suggest that combining the DTC-PGT with a careful physician consultation may be effective at motivating people toward preventive behavior.

Inverse Association Between Height-Increasing Alleles and Extreme Longevity in Japanese Women.

Growth hormone (GH)/insulin-like growth factor-1 (IGF-1)/insulin signaling is one of the most plausible biological pathways regulating aging and longevity. Previous studies have demonstrated that several single nucleotide polymorphisms (SNPs) in the GH/IGF-1/insulin signaling-associated genes influence both longevity and adult height, suggesting the possibility of a shared genetic architecture between longevity and height. We therefore examined the relationship between 30 height-associated SNPs and extreme longevity in a Japanese population consisting of 428 centenarians and 4,026 younger controls. We confirmed that height-increasing genetic scores (HGSs) constructed based on 30 SNPs were significantly associated with height in the controls (p = 6.95 × 10-23). HGS was significantly and inversely associated with extreme longevity in women (p = .011), but not in men, although no SNPs were significantly associated with extreme longevity after Bonferroni correction. The odds ratio for extreme longevity in the lowest HGS group (≤27) and the second lowest HGS group (28-30) relative to the highest HGS group (≥37) was 1.71 (p = .056) and 1.69 (p = .034), respectively, for women. In conclusion, the present study demonstrated an inverse association between height-increasing alleles with extreme longevity in Japanese women, providing novel insight into the genetic architecture of longevity and aging.

Relationship between pancreatic intraepithelial neoplasias, pancreatic ductal adenocarcinomas, and single nucleotide polymorphisms in autopsied elderly patients.

We comparatively analyzed serially autopsied, elderly Japanese patients (n = 2205) with pancreatic intraepithelial neoplasias (PanINs) and pancreatic ductal adenocarcinomas (PDACs) on the basis of their pancreatic lesions, clinical information, and single nucleotide polymorphisms (SNPs). The incidence of PanIN-1, -2, -3, and PDACs in these patients was 55%, 12%, 1.4%, and 2.4%, respectively. The occurrence of PanINs was associated with female sex, increasing age, and lower body mass index. We did not identify any common SNPs between PanINs and PDACs. There were no common SNPs associated with PanINs and PDACs between men and women. In previously reported pancreatic cancer-associated SNPs, rs3790844 (NR5A2) showed a significant correlation with PDAC in our cohort. Six SNPs (rs7016880, rs10096633, rs10503669, rs12678919, rs17482753, rs328) that were correlated with blood lipid levels were associated with the risk for PDACs. Our data suggest that different clinicopathological characteristics and predispositions may affect pancreatic carcinogenesis in elderly Japanese patients.

Identification of five genetic variants as novel determinants of type 2 diabetes mellitus in Japanese by exome-wide association studies.

We performed exome-wide association studies to identify single nucleotide polymorphisms that either influence fasting plasma glucose level or blood hemoglobin A1c content or confer susceptibility to type 2 diabetes mellitus in Japanese. Exome-wide association studies were performed with the use of Illumina Human Exome-12 DNA Analysis or Infinium Exome-24 BeadChip arrays and with 11,729 or 8635 subjects for fasting plasma glucose level or blood hemoglobin A1c content, respectively, or with 14,023 subjects for type 2 diabetes mellitus (3573 cases, 10,450 controls). The relation of genotypes of 41,265 polymorphisms to fasting plasma glucose level or blood hemoglobin A1c content was examined by linear regression analysis. After Bonferroni's correction, 41 and 17 polymorphisms were significantly (P < 1.21 × 10-6) associated with fasting plasma glucose level or blood hemoglobin A1c content, respectively, with two polymorphisms (rs139421991, rs189305583) being associated with both. Examination of the relation of allele frequencies to type 2 diabetes mellitus with Fisher's exact test revealed that 87 polymorphisms were significantly (P < 1.21 × 10-6) associated with type 2 diabetes mellitus. Subsequent multivariable logistic regression analysis with adjustment for age and sex showed that four polymorphisms (rs138313632, rs76974938, rs139012426, rs147317864) were significantly (P < 1.44 × 10-4) associated with type 2 diabetes mellitus, with rs138313632 and rs139012426 also being associated with fasting plasma glucose and rs76974938 with blood hemoglobin A1c. Five polymorphisms-rs139421991 of CAT, rs189305583 of PDCL2, rs138313632 of RUFY1, rs139012426 of LOC100505549, and rs76974938 of C21orf59-may be novel determinants of type 2 diabetes mellitus.

Early gestational maternal low-protein diet diminishes hepatic response to fasting in young adult male mice.

Maternal low-protein (MLP) diet can lead to hepatic steatosis, which only develops with ageing. It is still unclear whether the young offspring show any signs of past exposure to prenatal adverse conditions. We hypothesized that early nutritional insult would first affect the dynamic responsiveness to nutritional challenges rather than the static state. We analyzed the transcriptome and metabolome profiles of the hepatic response to fasting/refeeding in young male mice offspring to identify changes induced by early gestational MLP diet. Restricted MLP exposure strictly to early gestation was achieved by the embryo transfer method. As a result, the fasting-induced upregulation of genes related to long-chain fatty acid metabolism and of stress response genes related to protein folding were significantly diminished in MLP pups. Lipid profiling after fasting showed that the hepatic signature of triacylglycerols was shifted to longer acyl-chains and higher saturation by the MLP diet. Bioinformatic analyses suggested that these phenomenological changes may be partially linked to the peroxisome proliferator activated receptor α (PPARα) pathway. Taken together, early gestational MLP diet affected the hepatic dynamic response to nutritional stress in seemingly healthy young offspring, accompanied with partial deterioration of PPARα action.

Identification of TNFSF13, SPATC1L, SLC22A25 and SALL4 as novel susceptibility loci for atrial fibrillation by an exome­wide association study.

An exome­wide association study (EWAS) was performed to identify genetic variants, particularly low­frequency or rare coding variants with a moderate to large effect size, that confer susceptibility to atrial fibrillation in Japanese. The EWAS for atrial fibrillation was performed with 13,166 subjects (884 patients with atrial fibrillation and 12,282 controls) using an Illumina HumanExome­12 DNA Analysis BeadChip or Infinium Exome­24 BeadChip arrays. The association of atrial fibrillation with allele frequencies of 41,243 single nucleotide polymorphisms (SNPs) that passed quality control was examined with Fisher's exact test. Based on Bonferroni's correction, a P<1.21x10­6 was considered statistically significant. The EWAS for atrial fibrillation revealed that 122 SNPs were significantly associated with this condition. The association of the identified SNPs to atrial fibrillation was further examined by multivariable logistic regression analysis with adjustment for age, sex and the prevalence of hypertension. Eight SNPs were related (P<0.01) to atrial fibrillation, among which three polymorphisms, rs11552708 [G/A (G67R)]of TNF superfamily member 13 (TNFSF13; dominant model; P=9.36x10­9; odds ratio, 0.58), rs113710653 [C/T (E231 K)] of spermatogenesis and centriole associated 1 like (SPATC1L; dominant model; P=1.09x10­5; odds ratio, 3.27), and rs11231397 [G/C (R300T)] of solute carrier family 22 member 25 (SLC22A25; additive model; P=3.71x10­5; odds ratio, 1.77), were significantly (P<1.02x10­4) associated with this condition. The minor T allele of rs113710653 and the minor C allele of rs11231397 were risk factors for atrial fibrillation, whereas the minor A allele of rs11552708 was protective against this condition. In addition, rs77538589 [C/T (G117R)] of SALL4 exhibited a tendency to be associated with atrial fibrillation (dominant model; P=0.0002; odds ratio, 1.88), with the minor T allele representing a risk factor for this condition. TNFSF13, SPATC1L, SLC22A25 and SALL4 may thus be novel susceptibility loci for atrial fibrillation in the Japanese population.