Medical and surgical complications in pregnancy and obstetric labour complications in the Japan Environment and Children's Study (JECS) cohort: a birth cohort study.

This study aimed to describe the distribution of pregnancies with medical and obstetric complications based on the Japan Environment and Children's Study (JECS). We evaluated the distribution of the history of obstetric/gynaecological diseases, the history of obstetric labour complications, pregnancy with medical and surgical complications, and obstetric labour complications in participants in the JECS. Of 100,818 pregnant women with medical record entries after delivery, 15,305 (15.2%) had medical and surgical complications in pregnancy and 46,756 (46.4%) experienced obstetric labour complications. The proportion of pregnancies with heart disease, kidney disease and hepatitis was 0.3%, 0.3% and 0.1%, respectively. Gestational diabetes was diagnosed in 2715 (2.7%) women. The proportion of women with mild and severe gestational hypertension was 2.3% and 1%, respectively. The JECS is the largest birth cohort in Japan. These data will provide useful, basic information for perinatal care in Japan.IMPACT STATEMENTWhat is already known on this subject? Epidemiological studies have suggested that pre-existing diseases and complications of pregnancy, such as heart disease in pregnancy, gestational hypertension and gestational diabetes, may have implications for pregnancy outcomes, as well as for children's health and development.What the results of this study add? We evaluated the distribution of the history of obstetric/gynaecological diseases, the history of obstetric labour complications, medical and surgical complications in pregnancy, and obstetric labour complications using data from the Japan Environment and Children's Study (JECS).What the implications are of these findings for clinical practice and/or further research? The JECS is the largest birth cohort in Japan. Our data will provide useful, basic information for perinatal care in Japan.

Frequency of Common Copy-Number Variations at 15q11.2q13 in Sperm of Healthy Men.

The genomic region at 15q11.2q13 represents a hotspot for copy-number variations (CNVs) due to nonallelic homologous recombination. Previous studies have suggested that the development of 15q11.2q13 deletions in sperm may be affected by seasonal factors because patients with Prader-Willi syndrome resulting from 15q11.2q13 deletions on paternally derived chromosomes showed autumn-dominant birth seasonality. The present study aimed to determine the frequency of 15q11.2q13 CNVs in sperm of healthy men and clarify the effects of various environmental factors, i.e., age, smoking status, alcohol intake, and season, on the frequency. Thirty volunteers were asked to provide semen samples and clinical information once in each season of a year. The rates of 15q11.2q13 CNVs were examined using 2-color FISH. The results were statistically analyzed using a generalized estimating equation with negative binomial distribution and a log link function. Consequently, informative data were obtained from 83 samples of 26 individuals. The rates of deletions and duplications ranged from 0.04 to 0.48% and from 0.08 to 0.30%, respectively. The rates were not correlated with the age, smoking status, or alcohol intake. Sperm produced in winter showed 1.2 to 1.4-fold high rates for both deletions and duplications as compared with sperm produced in the other seasons; however, there was no significant difference. These results demonstrate high and variable CNV rates at 15q11.2q13 in sperm of healthy men. These CNVs appear to occur independent of the age, smoking status, or alcohol intake, while the effect of season remains inconclusive. Our results merit further validation.

Prevalence of Congenital Anomalies in the Japan Environment and Children's Study.

BACKGROUND: The aims of the present report were to estimate the prevalence of congenital anomalies (CAs) among infants in Japan using data from the Japan Environment and Children's Study (JECS) and to evaluate the validity of CA classification within JECS. METHODS: Data on CAs were collected at delivery and at age 1 month from the medical records of 101,825 infants at 15 regional centers. The analyses focused on 61 CAs, selected on the basis of reported associations with environmental exposure. Prevalence per 10,000 pregnancies (including miscarriages, stillbirths, and live births) was stratified according to four reporting patterns (at delivery, at age 1 month, at either, and at both). To evaluate the accuracy of observed CA prevalence, the medical records of 179 cases from a single JECS regional center underwent independent, retrospective re-evaluation. RESULTS: The prevalence of major CAs in four reporting patterns (at delivery, at age 1 month, at either, and at both) was 2.4, 2.6, 3.5, and 1.4 for myelomeningocele/spina bifida; 4.3, 4.2, 5.3, and 3.2 for cleft palate; 18.1, 17.4, 19.5, and 15.1 for cleft lip with or without cleft palate; 73.4, 100.3, 120.8, and 52.8 for congenital heart disease; and 10.5, 14.1, 15.0, and 9.6 for Down's syndrome, respectively. In the subsample re-evaluation, CA diagnoses were confirmed for 92.7%, 93.3%, 90.5%, and 97.8% of cases in the four reporting patterns (at delivery, at age 1 month, at either, and at both), respectively. CONCLUSIONS: The present report generated reliable data concerning the prevalence of major CAs in JECS.

Complications and adverse outcomes in pregnancy and childbirth among women who conceived by assisted reproductive technologies: a nationwide birth cohort study of Japan environment and children's study.

BACKGROUND: Although pregnancies conceived by assisted reproductive technology (ART) have a higher risk of maternal/perinatal complications, the overall risk of adverse outcomes necessitating advanced obstetric care has not been closely examined. The present study aimed to assess and compare the risk of maternal/perinatal complications and adverse outcomes in pregnancy and childbirth conceived by ART with those conceived naturally. METHODS: This study was conducted as a part of the Japan environment and children's study (JECS), an ongoing nationwide birth cohort study in Japan. The risk of maternal/perinatal complications and adverse outcomes was assessed by mode of conception (natural conception, ovulation induction [OI] without ART, conventional in vitro fertilization and embryo transfer [IVF-ET], or intracytoplasmic sperm injection [ICSI]) using logistic regression and generalized estimating equations controlling for potential confounders. RESULTS: The final dataset included women who conceived naturally (N = 90,506), by OI without ART (N = 3939), by conventional IVF-ET (N = 1476), and by ICSI (N = 1671). Compared with women who conceived naturally, those who conceived by conventional IVF-ET were at higher risk of placenta previa (adjusted OR 2.90 [95% CI 1.94, 4.34]), morbidly adherent placenta (6.85 [3.88, 12.13]), and pregnancy-induced hypertension (1.40 [1.10, 1.78]) whereas those who conceived by ICSI had a higher risk of placental abruption (2.16 [1.20, 3.88]) as well as placenta previa (2.01 [1.29, 3.13]) and morbidly adherent placenta (7.81 [4.56, 13.38]). Women who conceived by ART had a higher risk of blood transfusion (conventional IVF-ET: 3.85 [2.52, 5.88]; ICSI: 3.76 [2.49, 5.66]) and ICU admission (conventional IVF-ET: 2.58 [1.11, 6.01]; ICSI: 3.45 [1.68, 7.06]) even after controlling for potential confounders. Neonates conceived by ART had a higher risk of preterm birth (conventional IVF-ET: 1.42 [1.13, 1.78]; ICSI: 1.31 [1.05, 1.64]). CONCLUSIONS: Women who conceived by ART had a higher risk of maternal/perinatal complications necessitating advanced obstetric care. Obstetricians should be aware of the increased risk of adverse outcomes among this population.

Delayed peak response of cortisol to insulin tolerance test in patients with Prader-Willi syndrome.

Deaths among children with Prader-Willi syndrome (PWS) are often related to only mild or moderate upper respiratory tract infections, and many causes of death remain unexplained. Several reports have hypothesized that patients with PWS may experience latent central adrenal insufficiency. However, whether PWS subjects suffer from alteration of the hypothalamus-pituitary-adrenal (HPA) axis remains unclear. This study aimed to explore the HPA axis on PWS. We evaluated the HPA axis in 36 PWS patients (24 males, 12 females; age range, 7 months to 12 years; median age 2.0 years; interquartile range [IQR], 1.5-3.4 years) using an insulin tolerance test (ITT) in the morning between 08:00 and 11:00. For comparison, ITT results in 37 age-matched healthy children evaluated for short stature were used as controls. In PWS patients, basal levels of adrenocorticotropic hormone (ACTH) were 13.5 pg/ml (IQR, 8.3-27.5 pg/ml) and basal levels of cortisol were 18.0 µg/dl (IQR, 14.2-23.7 µg/dl). For all patients, cortisol levels at 60 min after stimulation were within the reference range (>18.1 µg/dl), with a median peak of 41.5 µg/dl (IQR, 32.3-48.6 µg/dl). Among control children, basal level of ACTH and basal and peak levels of cortisol were 10.9 (IQR, 8.5-22.0 pg/ml), 15.6 (IQR, 11.9-21.6 µg/dl), and 27.8 µg/dl (IQR, 23.7-30.5 µg/dl), respectively. Basal and peak levels of cortisol were all within normal ranges, but peak response of cortisol to ITT was delayed in the majority of PWS patients (64%). Although the mechanism remains unclear, this delay may signify the existence of central obstacle in adjustment of the HPA axis.

Comprehensive screening for monogenic diabetes in 89 Japanese children with insulin-requiring antibody-negative type 1 diabetes.

BACKGROUND: Mutations in causative genes for neonatal diabetes or maturity-onset diabetes of the young have been identified in multiple patients with autoantibody-negative type 1 diabetes (T1D). OBJECTIVES: We aimed to clarify the prevalence and phenotypic characteristics of monogenic abnormalities among 89 children with autoantibody-negative insulin-requiring T1D. METHODS: Mutations in 30 genes were screened using next-generation sequencing, and copy-number alterations of 4 major causative genes were examined using multiplex-ligation-dependent probe amplification. We compared the clinical characteristics between mutation carriers and non-carriers. RESULTS: We identified 11 probable pathogenic substitutions (6 in INS , 2 in HNF1A , 2 in HNF4A , and 1 in HNF1B ) in 11 cases, but no copy-number abnormalities. Only 2 mutation carriers had affected parents. De novo occurrence was confirmed for 3 mutations. The non-carrier group, but not the carrier group, was enriched with susceptible HLA alleles. Mutation carriers exhibited comparable phenotypes to those of non-carriers, except for a relatively normal body mass index (BMI) at diagnosis. CONCLUSIONS: This study demonstrated significant genetic overlap between autoantibody-negative T1D and monogenic diabetes. Mutations in INS and HNF genes, but not those in GCK and other monogenic diabetes genes, likely play critical roles in children with insulin-requiring T1D. This study also suggests the relatively high de novo rates of INS and HNF mutations, and the etiological link between autoimmune abnormalities and T1D in the non-carrier group. Carriers of monogenic mutations show non-specific phenotypes among all T1D cases, although they are more likely to have a normal BMI at diagnosis than non-carriers.

Regional differences in infant 25-Hydroxyvitamin D: Pilot study of the Japan Environment and Children's Study.

BACKGROUND: In recent years, a resurgence in the number of infants with vitamin D deficiency has been noted. In addition to seasonal differences in exposure to ultraviolet (UV) rays, regional differences in dietary habits and lifestyles may affect susceptibility to vitamin D deficiency. No studies have been conducted, however, on infants in multiple regions of Japan to determine the extent of differences in vitamin D status. METHODS: 25-Hydroxyvitamin D (25OHD) was measured on radioimmunoassay in 126 infants aged 2-4 years, who participated in the Pilot Study of the Japan Environment and Children's Study (JECS) by the Ministry of Environment of Japan. A multiple regression model with 25OHD level as the outcome variable, and season and region as explanatory variables, was generated. RESULTS: Both region and season during which infants participated in this study significantly affected 25OHD level (P = 0.0087 and <0.0001, respectively; Wald test). Reflecting decreased exposure to UV rays, infants who were examined in winter had lower 25OHD than those examined in summer. Infants from both Fukuoka Prefecture (33°N) and Kumamoto Prefecture (32°N), however, had lower 25OHD than those from Tochigi Prefecture (36°N), contrary to expectations given the extent of UV exposure. CONCLUSIONS: Regional differences in daily habits and/or environmental factors affect 25OHD level in Japanese infants. The JECS is expected to identify those factors to provide guidance on preventing infantile vitamin D deficiency.

Comparative study on three different methods for arm-span measurement: the Japan environment and Children's study pilot.

BACKGROUND: Arm span is an important measure for the assessment of growth and hormone deficiency diseases. In an epidemiological survey, with a large number of subjects' indicators, it is especially valuable to establish methods which can measure both quickly and accurately. However, there are various methods, and the length of arm span may vary according to the medical institution. METHODS: The arm span of nine 6-year old subjects was measured using two institutional standard methods, A and B, and a third method C which is an improved method and has been used for the first time in this study. A, No-Wall, with heels together the child stretches the arms out to the sides. B, Wall & No-Line, the child stands against the wall with heels together and spreads the arms against the wall. C, Wall & Line, the method is the same as B except a paper with horizontal lines is placed on the wall. We measured twice by each method. RESULTS: The difference between the 1st and 2nd measurements was marginally significantly smaller by using method of C. CONCLUSION: The method C, which we improved, is the best way to measure arm span.

Decline of CSF orexin (hypocretin) levels in Prader-Willi syndrome.

Prader-Willi syndrome is a congenital neurodevelopmental disorder resulting from deletion of the paternal copies of genes within the chromosome region 15q11-q13. Patients with Prader-Willi syndrome often exhibit excessive daytime sleepiness, excessive appetite, and obesity. As is the case in narcolepsy, orexin (hypocretin) may be responsible for these symptoms. However, reports showing cerebrospinal fluid orexin levels in Prader-Willi syndrome patients have been limited. The aim of this study was to examine the relationship between the characteristic symptoms of Prader-Willi syndrome and cerebrospinal fluid orexin levels. We clinically identified 14 Prader-Willi syndrome patients and examined their cerebrospinal fluid orexin levels. A total of 12 patients with a 15q11-q13 deletion and two patients with maternal uniparental disomy of chromosome 15 were identified. A total of 37 narcoleptic patients and 14 idiopathic hypersomnia patients were recruited for comparison. Cerebrospinal fluid orexin levels (median [25-75 percentiles]) in the 14 Prader-Willi syndrome patients were intermediate (192 [161-234.5] pg/ml), higher than in the narcoleptic patients, but lower than in the idiopathic hypersomnia patients. Body mass index of the Prader-Willi syndrome patients was higher than in the narcoleptic and idiopathic hypersomnia patients. There was also a negative correlation between Epworth sleepiness scale scores and orexin levels in Prader-Willi syndrome patients. Decreased cerebrospinal fluid orexin levels in Prader-Willi syndrome may play an important role in severity of obesity and excessive daytime sleepiness.

Human glutathione S-transferase A (GSTA) family genes are regulated by steroidogenic factor 1 (SF-1) and are involved in steroidogenesis.

Steroidogenic factor 1 (SF-1) is a master regulator for steroidogenesis. In this study, we identified novel SF-1 target genes using a genome-wide promoter tiling array and a DNA microarray. SF-1 was found to regulate human glutathione S-transferase A (GSTA) family genes (hGSTA1-hGSTA4), a superfamily of detoxification enzymes clustered on chromosome 6p12. All hGSTA genes were up-regulated by transduction of SF-1 into human mesenchymal stem cells, while knockdown of endogenous SF-1 in H295R cells down-regulated all hGSTA genes. Chromatin immunoprecipitation assays, however, revealed that SF-1 bound directly to the promoters of hGSTA3 and weakly of hGSTA4. Chromosome conformation capture assays revealed that the coordinated expression of the genes was based on changes in higher-order chromatin structure triggered by SF-1, which enables the formation of long-range interactions, at least between hGSTA1 and hGSTA3 gene promoters. In steroidogenesis, dehydrogenation of the 3-hydroxy group and subsequent Δ(5)-Δ(4) isomerization are thought to be enzymatic properties of 3ß-hydroxysteroid dehydrogenase (3ß-HSD). Here, we demonstrated that, in steroidogenic cells, the hGSTA1 and hGSTA3 gene products catalyze Δ(5)-Δ(4) isomerization in a coordinated fashion with 3ß-HSD II to produce progesterone or Δ(4)-androstenedione from their Δ(5)-precursors. Thus, hGSTA1 and hGSTA3 gene products are new members of steroidogenesis working as Δ(5)-Δ(4) isomerases.

Female-dominant estrogen production in healthy children before adrenarche.

OBJECTIVE: Ultra-sensitive hormone assays have detected slight sex differences in blood estradiol (E2) levels in young children before adrenarche. However, the origin of circulating E2 in these individuals remains unknown. This study aimed to clarify how E2 is produced in young girls before adrenarche. DESIGN: This is a satellite project of the Japan Environment and Children's Study organized by the National Institute for Environmental Studies. METHODS: We collected blood samples from healthy 6-year-old Japanese children (79 boys and 71 girls). Hormone measurements and data analysis were performed in the National Institute for Environmental Studies and the Medical Support Center of the Japan Environment and Children's Study, respectively. RESULTS: E2 and follicle stimulating hormone (FSH) levels were significantly higher in girls than in boys, while dehydroepiandrosterone sulfate (DHEA-S) and testosterone levels were comparable between the two groups. Girls showed significantly higher E2/testosterone ratios than boys. In children of both sexes, a correlation was observed between E2 and testosterone levels and between testosterone and DHEA-S levels. Moreover, E2 levels were correlated with FSH levels only in girls. CONCLUSIONS: The results indicate that in 6-year-old girls, circulating E2 is produced primarily in the ovary from adrenal steroids through FSH-induced aromatase upregulation. This study provides evidence that female-dominant E2 production starts several months or years before adrenarche. The biological significance of E2 biosynthesis in these young children needs to be clarified in future studies.

Risky Health Behaviors of Teenage Mothers and Infant Outcomes in the Japan Environment and Children's Study: A Nationwide Cohort Study.

STUDY OBJECTIVE: Few studies have investigated the risky health behaviors and psychosocial characteristics of teenage mothers in countries with a low teenage birth rate, like Japan. We examined the differences in maternal prenatal risky health behaviors and psychosocial characteristics, and birth weight of infants between teenage and adult mothers. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: We identified 1159 teenage (age younger than 20 years) and 73,547 adult mothers (20-34 years) who participated a nationwide birth cohort study between 2011 and 2014. Behavioral and psychosocial characteristics were ascertained using questionnaires during pregnancy. Birth weight of infants was verified through medical records. Univariate and multivariable logistic regression were used to assess the association of teenage motherhood and birth weight of infants with parity, marital status, household income, maternal education, job status, preconception body mass index, gestational weight gain, psychological distress, and smoking status. RESULTS: Teenage mothers were significantly more likely to smoke and have psychological distress and less likely to use alcohol than adult mothers (9.9% vs 4.6%, P < .001; 8.9% vs 3.4%, P < .001; 1.3% vs 2.5%, P < .001, respectively). No association was found between teenage motherhood and low birth weight in infants (odds ratio 0.99; 95% confidence interval, 0.73-1.32). Further, no association was found after adjusting for covariates. CONCLUSION: A substantially greater number of Japanese teenage mothers smoked and experienced severe psychological distress than adult mothers. Our findings will be useful for future research and for developing effective policies and programs for teenage mothers and their children.

Present status of prophylactic thyroidectomy in pediatric multiple endocrine neoplasia 2: a nationwide survey in Japan 1997-2017.

Background In Japan, prophylactic thyroidectomy involves out-of-pocket expense. The American Thyroid Association (ATA) recommends prophylactic thyroidectomy for medullary thyroid carcinoma (MTC) during early childhood in patients with multiple endocrine neoplasia type 2 (MEN2). The ATA reports a high frequency of postoperative complications in childhood, which also influenced the delay of prophylactic thyroidectomy in Japan. Methods This retrospective study of multiple medical centers in Japan included individuals aged <20 years diagnosed with germline RET mutations between 1997 and 2017. The onset and onset possibility were defined based on confirmed lesions or calcitonin levels. The definition of risk and prophylactic thyroidectomy were based on the ATA 2015 revised guideline. Results Twenty-one patients with MEN2 were enrolled (highest risk, n = 5; high risk, n = 5; and moderate risk, n = 11). The cumulative incidence of the onset/onset possibility reached 50% at 5 and 8 years and 100% at 9 years and 17 years in high- and moderate-risk patients, respectively. Of 7 patients with MEN2A, 71% underwent prophylactic thyroidectomy. Only one 5-year-old patient (C634Y) had increased serum calcitonin level after prophylactic thyroidectomy in the MEN2A group. The only permanent complication, which did not occur in patients who underwent total thyroidectomy alone, was hypoparathyroidism (33% of patients). This permanent complication occurred with clinically developed MTC. No permanent postoperative complications occurred in patients aged 5-6 years. Conclusions Prophylactic thyroidectomy reduces recurrence and postoperative complications in pediatric patients with MEN2. Early thyroidectomy based on only calcitonin level could possibly reduce thyroidectomy delay.

Aberrant, autistic, and food-related behaviors in adults with Prader-Willi syndrome. The comparison between young adults and adults.

This study aims to explore the differences of age as well as genotype in regards to the severity of behavioral symptoms in Prader-Willi syndrome (PWS), with emphasis on the comparison between youngadults and adults.The Food Related Problem Questionnaire (FRPQ), the Aberrant Behavior Checklist Japanese Version (ABC-J), and the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS) were administered to 46 PWS patients, including 33 young adults (ages 18-28) and 13 adults(ages 30-45). To examine the differences between young adults and adults, Mann-Whitney U tests were conducted. Statistically significant differences were found in ABC-J (p = .027) and PARS (p = .046), with higher scores in young adults than adults. Such differences between the two age groups were still true for the subgroups having a paternal chromosome 15q deletion (DEL) for ABC-J (p = .050) and part of PARS ("Problematic behavior"; p = .007). By contrast, there was no significant differences between young adults and adults regarding FRPQ (p = .65).These results suggest that aberrant behaviors decline from around the ages of thirty, in PWS patients in general and in DEL subgroups in particular, while food-related behaviors give no indication of diminishing in spite of developmental growth.

Autistic, Aberrant, and Food-Related Behaviors in Adolescents and Young Adults with Prader-Willi Syndrome: The Effects of Age and Genotype.

The effects of age and genotype were examined, with regard to the severity of aberrant, autistic, and food-related behaviors in Prader-Willi syndrome (PWS), with an emphasis on the contrast between adolescents and young adults. The Aberrant Behavior Checklist Japanese version (ABC-J), the Food Related Problem Questionnaire (FRPQ), and the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS) were administered to 65 PWS patients, including 20 adolescents (ages 12 to 17) and 45 young adults (ages 18 to 29). Significant differences (Mann-Whitney U tests) were found in ABC-J (p = 0.004) and PARS (p = 0.021), with lower scores in adolescents than in young adults. While DEL subgroups showed no significant differences between the two age groups in ABC-J (p = 0.063) and PARS (p = 0.134), mUPD subgroups showed a statistically significant difference in terms of ABC-J (p = 0.007). No significant differences were found between adolescents and young adults, in terms of FRPQ (p = 0.163). These results suggest that aberrant and autistic behaviors follow a marked worsening trend from around the age of 18. On the other hand, food-related behaviors give no sign of change at this transitory stage. Young adults with mUPD were found to be significantly more severe than adolescents with mUPD, in terms of aberrant behaviors.

Allergic profiles of mothers and fathers in the Japan Environment and Children's Study (JECS): a nationwide birth cohort study.

BACKGROUND: The Japan Environment and Children's Study (JECS) is a nationwide, multicenter, prospective birth cohort investigation launched by the Ministry of Environment in Japan. The purpose of the JECS is to evaluate the influence of prenatal and postnatal exposures to environmental factors on the postnatal health of the children. In this study, we evaluated the allergic characteristics of parents within the JECS cohort. METHODS: This study covered a wide geographical area and encompassed 15 regional centers. We obtained information regarding doctor diagnosed allergic diseases by using maternal and/or paternal self-administered questionnaires during the first trimester of pregnancy. Blood samples were also obtained from mothers and/or fathers to detect serum IgE concentrations. RESULTS: The prevalences of asthma, allergic rhinitis (hay fever), atopic dermatitis, and food allergy were 10.9, 36.0, 15.7 and 4.8%, respectively, among 99,013 mothers; these prevalences among 49,991 fathers were 10.8, 30.3, 11.2 and 3.3%, respectively. Any positive antigen-specific IgE sensitization was found in 73.9% of mothers. The most abundant antigen sensitization in mothers was to Japanese cedar (55.6%), followed by Der p 1 (48%); only 1.0% of mothers were sensitized to egg white. CONCLUSIONS: This is the first epidemiological report on allergic disorders and allergen sensitization of parents during pregnancy among the Japanese general population.

Nucleotide substitutions in CD101, the human homolog of a diabetes susceptibility gene in non-obese diabetic mouse, in patients with type 1 diabetes.

AIMS/INTRODUCTION: Although genome-wide association studies have identified more than 50 susceptibility genes for type 1 diabetes, low-frequency risk variants could remain unrecognized. The present study aimed to identify novel type 1 diabetes susceptibility genes by newly established methods. MATERIALS AND METHODS: We carried out whole-exome sequencing and genome-wide copy-number analysis for a Japanese family consisting of two patients with type 1 diabetes and three unaffected relatives. Further mutation screening was carried out for 127 sporadic cases. The functional consequences of identified substitutions were evaluated by in silico analyses and fluorescence-activated cell sorting of blood samples. RESULTS: Whole-exome sequencing and genome-wide copy-number analysis of familial cases showed co-segregation of the p.V863L substitution in CD101, the human homolog of an autoimmune diabetes gene in the non-obese diabetic mouse, with type 1 diabetes. Mutation screening of CD101 in 127 sporadic cases detected the p.V678L and p.T944R substitutions in two patients. The p.V863L, p.V678L and p.T944R substitutions were absent or extremely rare in the general population, and were assessed as 'probably/possibly damaging' by in silico analyses. CD101 expression on monocytes, granulocytes and myeloid dendritic cells of mutation-positive patients was weaker than that of control individuals. CONCLUSIONS: These results raise the possibility that CD101 is a susceptibility gene for type 1 diabetes.

Pyruvate Improved Insulin Secretion Status in a Mitochondrial Diabetes Mellitus Patient.

CONTEXT: Mitochondrial diabetes is a rare form of diabetes mellitus accounting for up to 1% of all diabetes. Pyruvate therapy has been reported to be a potential therapeutic choice for patients with mitochondrial diseases. CASE DESCRIPTION: Water-based sodium pyruvate solutions (0.5 g/kg, thrice daily) were administrated orally to a 32-year-old Japanese male with mitochondrial diabetes and myopathy caused by m.14709T>C mutation. At the age of 20 years, he was diagnosed with diabetes mellitus and started insulin therapy. He tested negative for islet cell and glutamic decarboxylase antibodies. To evaluate favorable therapeutic improvements, we measured the lactate and pyruvate levels in plasma and cerebrospinal fluid; urinary C-peptide, glycated hemoglobin, and glycoalbumin levels; and total daily insulin dose (TDD). The patient experienced no side effects such as diarrhea because of pyruvate therapy. His urinary C-peptide level improved from 4.3 to 17.2 µg/d after 1 day and to 30.2 µg/d after 6 months of pyruvate therapy. TDD decreased from 33 to 20 U/d after 6 months of pyruvate therapy, but the lactate levels of plasma and cerebrospinal fluid and the lactate/pyruvate ratio did not change. CONCLUSIONS: Sodium pyruvate improved insulin secretion and resulted in decreased TDD in a patient with mitochondrial diabetes. Pyruvate therapy may be a potential therapeutic choice for patients with mitochondrial diabetes. Clinical trials involving a larger number of patients and long-term evaluation of the therapy are necessary to clarify the efficacy of pyruvate therapy.