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Silver-Russel syndrome (SRS) is a representative imprinting disorder (ID) characterized by growth failure and diagnosed by clinical features. Recently, international consensus has recommended using the Netchine-Harbison clinical scoring system (NH-CSS) as clinical diagnostic criteria. Loss of methylation of H19/IGF2:intergenic differentially methylated region (H19LOM) and maternal uniparental disomy chromosome 7 (UPD(7)mat) are common etiologies of SRS; however, other IDs, pathogenic variants (PVs) of genes, and pathogenic copy number variants (PCNVs) have been reported in patients meeting NH-CSS. To clarify the frequency and clinical characteristics of each etiology, we conducted (epi)genetic analysis in 173 patients satisfying NH-CSS. H19LOM and UPD(7)mat were identified in 34.1%. PCNVs, other IDs, and PVs were in 15.0%. Patients with all six NH-CSS items were most frequently observed with H19LOM and UPD(7)mat. This study confirmed the suitability of NH-CSS as clinical diagnostic criteria, the (epi)genetic heterogeneity of SRS, and showed the necessity of further discussion regarding the "SRS spectrum".

Loss of methylation (LOM) at GNAS-A/B:TSS-differentially methylated regions (DMRs) in the GNAS locus is observed in pseudohypoparathyroidism type 1B (PHP1B). Many PHP1B cases are sporadic, but autosomal dominant-PHP1B has a deletion involving NESP55 expressed from the maternal allele or STX16 located upstream of the GNAS locus on the maternal allele. We report the possible first familial PHP1B cases with retrotransposon insertion in the GNAS locus on the maternal allele. To our knowledge, they are the possible first cases with imprinting disorders caused by retrotransposon insertion. The two sibling cases experienced tetany and/or cramps from school age and had hypocalcemia and an increased serum intact parathyroid hormone (PTH) level together with overweight, round face, and normal intellectual levels. Methylation analysis for DMRs in the GNAS locus showed only LOM of the GNAS-A/B:TSS-DMR. Copy number abnormalities at STX16 and the GNAS locus were not detected by array comparative genomic hybridization. Whole-genome sequencing and Sanger sequencing revealed an approximately 1000-bp SVA retrotransposon insertion upstream of the first exon of A/B on the GNAS locus in these siblings. Whole-genome methylome analysis by Enzymatic Methyl-Seq in the siblings showed normal methylation status in the region surrounding the insertion site and mild LOM of the GNAS-A/B:TSS-DMR. We conducted transcriptome analysis using mRNA from skin fibroblasts and induced pluripotent stem cells (iPSCs) derived from the siblings and detected no aberrant NESP55 transcripts. Quantitative reverse-transcriptase PCR (qRT-PCR) analysis in skin fibroblasts showed increased A/B expression in the patients and no NESP55 expression, even in a control. qRT-PCR analysis in iPSCs showed decreased NESP55 expression with normal methylation status of the GNAS-NESP:TSS-DMR in the patients. The retrotransposon insertion in the siblings likely caused decreased NESP55 expression that could lead to increased A/B expression via LOM of the GNAS-A/B:TSS-DMR, subsequent reduced Gsα expression, and finally, PHP1B development. © 2022 American Society for Bone and Mineral Research (ASBMR).

Atrophic autoimmune thyroiditis (AAT) is a type of autoimmune hypothyroidism without goiter. TSH receptor-blocking antibodies (TSBAb) are involved in its etiology in adults. Reportedly, this disease is extremely rare in children. In this study, we aimed to investigate the prevalence of TSBAb during AAT onset in children using a commercially available cell-based bioassay TSAb kit. We conducted a multicenter retrospective observational study. We collected data of patients with AAT who were < 15 yr old, enrolled in a collaborative research group, and diagnosed since July 2003. AAT was defined as acquired autoimmune hypothyroidism without thyroid enlargement. Eighteen patients (including 15 females) whose TSH receptor antibody (TRAb) or TSBAb levels were measured within a year from the initial visit were included. The median age at diagnosis was 9.3 years, and the estimated time between onset and diagnosis was 2.6 yr. The positive rate for either TSBAb or TRAb was 38.8% (95% confidence interval: 18.3–59.5%). There were no significant differences in age, the estimated time between onset and diagnosis, and FT4 levels at diagnosis between the TSBAb-positive and -negative groups. Unlike previous reports, we showed that the prevalence of TSBAb-positivity in childhood-onset AATs is not rare, as in adults.

Background More than 40 years have passed since the introduction of newborn screening programs (NBS) for congenital hypothyroidism (CH), and there have been many reports on the long-term outcome of CH identified by NBS. There are some reports that CH is associated with early adiposity rebound and adult obesity. On the other hand, the association between AR and CH has not been revealed in Japan. Objective The aim of this study was to evaluate the timing of AR in individuals with CH detected by NBS in our institution, furthermore, to find out the risk factors of early AR in CH individuals. Patients and Methods The study included 212 CH children (105 female/107 males) who were ten years of age or older as of September 2021. We retrospectively collected height and weight data from one to ten years of age, and the timing of AR was visually determined. We examined the association between the AR age and the severity of hypothyroidism at NBS and at the first visit. Results The median AR age was 5.6 years for boys and 6.2 years for girls, which was unexpectedly not unexpectedly younger than that of the general Japanese population reported by Koyama (4.8 ± 1.4 years for boys, 4.7 ± 1.5 years for girls). Data from 115 patients (107 males, 105 females) whose physique data between the age of 15 and 18 were available showed that body mass index (BMI) was 21.1±3.2 kg/m2 for males and 20.6±2.7 kg/m2 for females, positively correlated with AR age, and not significantly different from BMI at 15-19 years of age (21.1±3.6 for males and 20.2±2.2 for females) in the 2019 National Nutrition and Health Survey (p=0.790, p=0.619). NBS-FT4 was slightly positively correlated to AR age (r=0.234, p=0. 0315). We found that the AR age may be earlier and adult BMI may be higher in CH patients without ossification of the distal femoral epiphyseal nucleus at first evaluation. Discussion Severe fetal hypothyroidism may cause an absence of mineralization of the distal femoral epiphyses in the neonatal period. Our results indicate that severe fetal hypothyroidism, even if diagnosed and treated at neonatal, contributes to the development of adult obesity. Conclusion The AR age and BMI at 15-18 years of CH are not significantly different from the general population. However, severe fetal hypothyroidism could result in adult obesity. Presentation: No date and time listed

Background(Epi)genetic disorders associated with small-for-gestational-age with short stature (SGA-SS) include imprinting disorders (IDs). Silver-Russell syndrome (SRS) is a representative ID in SGA-SS and has heterogenous (epi)genetic causes.Subjects and MethodsTo clarify the contribution of IDs to SGA-SS and the molecular and phenotypic spectrum of SRS, we recruited 269 patients with SGA-SS, consisting of 103 and 166 patients referred to us for genetic testing for SGA-SS and SRS, respectively. After excluding 20 patients with structural abnormalities detected by comparative genomic hybridization analysis using catalog array, 249 patients were classified into 3 subgroups based on the Netchine-Harbison clinical scoring system (NH-CSS), SRS diagnostic criteria. We screened various IDs by methylation analysis for differentially methylated regions (DMRs) related to known IDs. We also performed clinical analysis.ResultsThese 249 patients with SGA-SS were classified into the “SRS-compatible group” (n = 148), the “non-SRS with normocephaly or relative macrocephaly at birth group” (non-SRS group) (n = 94), or the “non-SRS with relative microcephaly at birth group” (non-SRS with microcephaly group) (n = 7). The 44.6% of patients in the “SRS-compatible group,” 21.3% of patients in the “non-SRS group,” and 14.3% in the “non-SRS with microcephaly group” had various IDs. Loss of methylation of the H19/IGF2:intergenic-DMR and uniparental disomy chromosome 7, being major genetic causes of SRS, was detected in 30.4% of patients in the “SRS-compatible group” and in 13.8% of patients in the “non-SRS group.”ConclusionWe clarified the contribution of IDs as (epi)genetic causes of SGA-SS and the molecular and phenotypic spectrum of SRS. Various IDs constitute underlying factors for SGA-SS, including SRS.

BackgroundZNF597, encoding a zinc-finger protein, is the human-specific maternally expressed imprinted gene located on 16p13.3. The parent-of-origin expression of ZNF597 is regulated by the ZNF597:TSS-DMR, of which only the paternal allele acquires methylation during postimplantation period. Overexpression of ZNF597 may contribute to some of the phenotypes associated with maternal uniparental disomy of chromosome 16 (UPD(16)mat), and some patients with UPD(16)mat presenting with Silver-Russell syndrome (SRS) phenotype have recently been reported.MethodsA 6-year-old boy presented with prenatal growth restriction, macrocephaly at birth, forehead protrusion in infancy and clinodactyly of the fifth finger. Methylation, expression, microsatellite marker, single nucleotide polymorphism array and trio whole-exome sequencing analyses were conducted.ResultsIsolated hypomethylation of the ZNF597:TSS-DMR and subsequent loss of imprinting and overexpression of ZNF597 were confirmed in the patient. Epigenetic alterations, such as UPD including UPD(16)mat and other methylation defects, were excluded. Pathogenic sequence or copy number variants affecting his phenotypes were not identified, indicating that primary epimutation occurred postzygotically.ConclusionWe report the first case of isolated ZNF597 imprinting defect, showing phenotypic overlap with SRS despite not satisfying the clinical SRS criteria. A novel imprinting disorder entity involving the ZNF597 imprinted domain can be speculated.

Context Children born small-for-gestational-age with short stature (SGA-SS) is associated with (epi)genetic defects, including imprinting disorders (IDs), pathogenic copy number variants (PCNVs), and pathogenic variants of genes involved in growth. However, comprehensive studies evaluating these 3 factors are very limited. Objective To clarify the contribution of PCNVs and candidate pathogenic variants to SGA-SS. Design Comprehensive molecular analyses consisting of methylation analysis, copy number analysis, and multigene sequencing. Methods We enrolled 140 patients referred to us for genetic testing for SGA-SS. Among them, we excluded 42 patients meeting Netchine–Harbison clinical scoring system criteria for Silver–Russell syndrome and 4 patients with abnormal methylation levels of the IDs-related differentially methylated regions. Consequently, we conducted copy number analysis and multigene sequencing for 86 SGA-SS patients with sufficient sample volume. We also evaluated clinical phenotypes of patients with PCNVs or candidate pathogenic variants. Results We identified 8 (9.3%) and 11 (12.8%) patients with PCNVs and candidate pathogenic variants, respectively. According to the American College of Medical Genetics standards and guidelines, 5 variants were classified as pathogenic and the remaining 6 variants were classified as variants of unknown significance. Genetic diagnosis was made in 12 patients. All patients with PCNVs or candidate pathogenic variants did not correspond perfectly to characteristic clinical features of each specific genetic cause. Conclusion We clarified the contribution of PCNVs and pathogenic variants to SGA-SS without IDs. Comprehensive molecular analyses, including copy number analysis and multigene sequencing, should be considered for patients with unknown SGA-SS etiology.

The patient was a 57-year-old male. He was diagnosed with locally advanced rectal cancer infiltrating the left levator ani muscle. Chemotherapy(S-1 plus L-OHP plus bevacizumab regimen)was started for the purpose of obtaining a negative circumferential radial margin. After the second course, he presented with perforation of the sigmoid colon for which an emergency operation was performed. The perforation was located 5 centimeters above the tumor in the sigmoid colon. We performed partial resection of the sigmoid colon to repair the perforation and create a sigmoid colostomy. CT, after the initial S-1 plus L-OHP plus bevacizumab chemotherapy regimen, revealed tumor shrinkage. Following 2 more courses of chemotherapy( S-1 plus L-OHP regimen), we performed transanal total mesenteric excision(taTME)as curative surgery. R0 resection was achieved. The combined transanal and laparoscopic approach was highly effective for a patient with pan-peritonitis.

The patient is a 40-year-old male. He was referred to our department because, after a thorough examination, he was diagnosed with rectal cancer. Preoperative imaging showed a tumor in the rectum at the level of the seminal vesicles, and left lateral invasion was suspected. In addition, lymph node metastases in the left lateral area were suspected. We performed a robot-assisted low anterior resection plus bilateral lateral dissection plus covering ileostomy for this patient after neoadjuvant chemotherapy. The operation time was 495 minutes, and the blood loss was 50 g. The histopathological diagnosis was pT3, N3(#263), M0, pStage Ⅲc, PM0, DM0, RM0, R0, Cur A. In Japan, robotic-assisted surgery for rectal cancer has been covered by insurance since April 2018, and in our department, robotic surgery is the first option for any stage or type of surgery for rectal cancer. We believe that the greatest advantages of robotic surgery for rectal cancer are in lateral dissection, ie, the better understanding of how blood vessels and nerves travel around the internal iliac vessels and the associated anatomy of pelvic organs that comes from reliable lateral dissection. We have experienced a case of safe robotic-assisted radical resection of laterally invasive rectal cancer, which is considered to be relatively difficult, and we hereby report the usefulness of the robotic-assisted modality.

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Adult men are, on average, ∼13 cm taller than adult women. Although previous studies have suggested a significant contribution of sex chromosomal genes to sexual dimorphism in height, all attempts to identify a male-specific growth gene have failed. In the present study, we analyzed transcripts from cartilage tissues, and found that the expression of SHOX, a growth-promoting gene in the pseudoautosomal region on the X and Y chromosomes, was lower in females than in males. DNA methylation analyses showed that SHOX has some characteristics of genes subjected to X chromosome inactivation (XCI). These findings indicate that sex difference in human height is mainly ascribed to incomplete spreading of XCI on a pseudoautosomal gene. More importantly, RT-PCR of fibroblast clones revealed XCI-independent random clonal monoallelic expression of SHOX. We presume that during eutherian evolution, SHOX translocated from an autosome to the proto-sex chromosome without losing the epigenetic memory of random clonal monoallelic expression and subsequently underwent partial XCI. This study provides a novel model of epigenetic gene regulation leading to phenotypic diversity in humans.

Congenital central hypothyroidism (C-CH) is defined as hypothyroidism due to a lack of stimulation of the normal thyroid gland (1, 2). C-CH is caused by anatomical or functional impairments in neurons that secrete hypothalamic-thyrotropin releasing hormone (TRH) and/or pituitary thyrotropes that secrete TSH. C-CH is more frequently recognized as a part of a combined pituitary hormone deficiency (CPHD), but a small proportion of C-CH cases demonstrate isolated C-CH where mainly TSH secretion is impaired. The frequency of C-CH among the general population has been reported as 1/16,000 to 1/30,000 (2–4). In Japan, newborn screening for congenital hypothyroidism has been performed since 1979. While the main purpose of such screening is to detect primary hypothyroidism (thyroid origin), some regions in the country employ simultaneous determination of blood TSH and free T4 (FT4) levels to diagnose C-CH in addition to primary hypothyroidism (2,3,4). Nagasaki et al. reported that C-CH occurs in about 10% of patients with congenital hypothyroidism in Japan (5). In 1971, Miyai et al. (6) first reported a family with isolated TSH deficiency, and in 1989, a mutation in the TSH gene (TSHB) encoding the β-subunit of the protein was eventually discovered (7). Thereafter, over the following three decades, several genetic defects associated with isolated C-CH have been identified (Table 1) (1, 2, 8, 9). This review summarizes the current knowledge regarding the genetic causes and clinical features of isolated C-CH. Table 1. Genetic causes, severity of hypothyroidism, and endocrine findings of isolated-Cent-H Open in a separate window TSHB Deficiency As mentioned, a family in Japan showing TSH deficiency was first reported by Miyai et al. (6), and eventually a mutation in TSHB was discovered in 1989 (7). In the first report, patients showed symptoms of severe congenital hypothyroidism, such as failure to thrive, prolonged jaundice, and developmental delay. Despite very low levels of serum T4 and T3, TSH was not measurable, indicating C-CH. A TRH stimulation test did not increase TSH level at all, but showed a normal PRL response. Finally, their group identified a homozygous mutation p.Gly29Arg in TSHB. Miyai et al. (1) further found several Japanese patients with TSHB deficiency. Genetic analysis showed that all patients had p.Gly29Arg, suggesting a founder effect (1). Since the first report, several patients with TSHB mutations have been reported worldwide (10,11,12,13,14,15,16,17,18,19,20). In all cases, the inheritance of TSHB defects is autosomal recessive. Almost all patients with a TSHB defect develop severe symptoms of congenital hypothyroidism after birth. A delay in diagnosis and thyroid hormone replacement therapy results in poorer psychomotor development. Regarding mutations, nonsense mutations (p.Glu32Ter and p.Gln69Ter), frameshift mutations (p.Cys125ValfsTer10), missense mutations (p.Met1?, p.Glu32Lys, p.Gly49Arg, p.Cys108Tyr, and p.Cys105Arg), and a splice site mutation (c.1625+5G>A) have been identified. One mutation (c.162G>A) did not cause an amino acid change, but it was located at the 5′ donor splice site of exon/intron2, leading to the skipping of exon 2. In addition, a homozygous deletion of TSHB was also reported (16). Among these mutations and deletions, p.Cys125ValfsTer10 has been most frequently reported in Europe, Argentina, and the USA (10, 12, 18,19,20). This mutation has been found in various unrelated families, but several studies using haplotype analysis in Germany, the UK, and Ireland showed that this mutation was derived from common ancestors (18,19,20).

There are as yet no cohort studies of hypoglycemia in type 1 diabetes before starting insulin therapy. Our aim was to determine the frequency and clinical features of hypoglycemia in patients with type 1A diabetes prior to commencing insulin therapy.Eighty-seven patients with type 1A diabetes were enrolled, and a retrospective chart review of the patients was conducted.Hypoglycemia before insulin therapy occurred in six of 87 patients (6.9%). The HbA1c levels at the diagnosis of type 1A diabetes in the hypoglycemia group were lower than in the non-hypoglycemia group (median: 7.3% (56 mmol/mol) vs. 11.9% (106 mmol/mol), p 0.0001). Similarly, the 24-hour urinary C-peptide (UCPR) levels of the former group were higher than those of the latter group (16.5 μg/day/mWe demonstrated that some patients with type 1A diabetes experience hypoglycemic episodes before insulin therapy. Patients with early-stage type 1A diabetes with relatively low HbA1c or high UCPR have a risk of hypoglycemia. These findings may impact when and how insulin is introduced in the treatment of early-stage type 1A diabetes.

Introduction Kallmann syndrome (KS) is a genetically heterogeneous condition characterized by hypogonadotropic hypogonadism (HH) and olfactory dysfunction. Although SOX10, a causative gene for Waardenburg syndrome (WS) and peripheral demyelinating neuropathy, central demyelination, WS, and Hirschsprung disease (PCWH) has previously been implicated in KS, the clinical significance of SOX10 variants as the cause of KS remains uncertain. Patients and Methods A total of 117 patients with KS underwent mutation screening of SOX10 and 14 other causative genes for KS/HH. Rare SOX10 variants were subjected to in silico and in vitro analyses. We also examined clinical data of the patients and their parents with SOX10 variants. Results Sequence analysis identified 2 heterozygous variants of SOX10 (c.1225G > T, p.Gly409* and c.475C > T, p.Arg159Trp) in patients 1–3, as well as in the parents of patients 1 and 3. The variants were assessed as pathogenic/likely pathogenic, according to the American College of Medical Genomics guidelines. Both variants lacked in vitro transactivating activity for the MITF promoter and exerted no dominant-negative effects. Patients 1–3 carried no pathogenic variants in other genes examined. The patients presented with typical KS, while such features were absent in the parents of patients 1 and 3. None of the 5 variant-positive individuals exhibited hypopigmentation, while 1 and 2 individuals exhibited complete and partial hearing loss, respectively. Conclusion These results provide evidence that SOX10 haploinsufficiency accounts for a small percentage of KS cases. SOX10 haploinsufficiency is likely to be associated with a broad phenotypic spectrum, which includes KS without other clinical features of WS/PCWH.

Background ILNEB constitute an autosomal recessive disorder caused by homozygous or compound heterozygous mutation of the gene for the ITGA3. To date, 8 ILNEB patients have been reported, but all 6 neonatal-onset ILNEB patients suffered early death within 2 years. The most common cause of death among previously reported ILNEB patients was exacerbation of the respiratory condition. Methods In this study, we describe a case of ILNEB with neonatal onset in a female patient and the genetic and histopathological testing performed. Results Our patient had a compound heterozygous mutation in ITGA3. Compared to previously reported patients, this patient exhibited milder clinical and histopathological characteristics. After experiencing a life-threatening respiratory infection at 8 months old, the patient started periodic subcutaneous immunoglobulin treatment once every 1-2 weeks for nephrotic-range proteinuria-induced secondary hypogammaglobulinemia. At the age of 3 years, proteinuria gradually increased with severe edema despite strict internal management. Therefore, our patient underwent unilateral nephrectomy and insertion of a peritoneal dialysis catheter followed by another unilateral nephrectomy. One month later, she underwent an ABO-compatible living-donor kidney transplantation at the age of 4 years. Conclusions Our patient is a neonatal-onset ILNEB patient who survived for more than 2 years and underwent successful kidney transplantation.

Context Aromatase excess syndrome (AEXS) is a very rare disorder characterized by prepubertal gynecomastia, bone age acceleration, and early growth arrest. Heterozygote submicroscopic rearrangements within the promotor of CYP19A1 result in overexpression of aromatase and enhanced aromatization of androgens. Objective The objective was to study long-term treatment effects of an aromatase inhibitor. Methods Data from 7 boys with AEXS were retrospectively collected. Genetic analysis revealed upstream of CYP19A1 a 165 901 bp deletion in 4 German cousins, a 198 662 bp deletion in 2 Japanese brothers, and a 387 622 bp tandem duplication in a Japanese boy. Results All boys developed prepubertal gynecomastia, at median 9.0 years of age (range: 7.0-11.0). Height was +1.20 standard deviation score (SDS) (–0.24 to +1.98); predicted adult height was -1.29 SDS (-3.29 to +1.09). Four boys were treated with 1.0 mg of anastrozole daily, while 3 reached adult height untreated. Treatment with anastrozole was stopped after 5.6 years (4.0-6.8). Three treated boys exceeded their prognosis by 2.4, 6.9, and 8.1 cm, while 1 untreated boy fell below the prognosis by 8.6 cm. One treated with a low dose and 2 untreated reached their prognosis. Adult heights were –0.91 SDS with anastrozole (–2.86 to –0.29) and –0.15 SDS without (–2.31 to –0.03). Distance to target height was –0.22 SDS with anastrozole (–1.72 to +0.52) and +0.54 SDS without (+0.23 to +1.30). Conclusion Spontaneous growth in AEXS varied, even in the same family. Our data suggest that early started, long-term inhibition by anastrozole promotes adult height in boys with AEXS.

BackgroundSilver-Russell syndrome (SRS) is characterized by growth failure and dysmorphic features. Major (epi)genetic causes of SRS are loss of methylation on chromosome 11p15 (11p15 LOM) and maternal uniparental disomy of chromosome 7 (upd(7)mat). However,IGF2,CDKN1C,HMGA2, andPLAG1mutations infrequently cause SRS. In addition, other imprinting disturbances, pathogenic copy number variations (PCNVs), and monogenic disorders sometimes lead to SRS phenotype. This study aimed to clarify the frequency and clinical features of the patients with gene mutations among etiology-unknown patients with SRS phenotype.ResultsMultigene sequencing was performed in 92 out of 336 patients referred to us for genetic testing for SRS. The clinical features of the patients were evaluated based on the Netchine-Harbison clinical scoring system. None of the patients showed 11p15 LOM, upd(7)mat, abnormal methylation levels for six differentially methylated regions (DMRs), namely,PLAGL1:alt-TSS-DMR on chromosome 6,KCNQ1OT1:TSS-DMR on chromosome 11,MEG3/DLK1:IG-DMR on chromosome 14,MEG3:TSS-DMR on chromosome 14,SNURF:TSS-DMR on chromosome 15, andGNAS A/B:TSS-DMR on chromosome 20, PCNVs, or maternal uniparental disomy of chromosome 16. Using next-generation sequencing and Sanger sequencing, we screened four SRS-causative genes and 406 genes related to growth failure and/or skeletal dysplasia. We identified four pathogenic or likely pathogenic variants in responsible genes for SRS (4.3%:IGF2in two patients,CDKN1C, andPLAG1), and five pathogenic variants in causative genes for known genetic syndromes presenting with growth failure (5.4%:IGF1Rabnormality (IGF1R), SHORT syndrome (PIK3R1), Floating-Harbor syndrome (SRCAP), Pitt-Hopkins syndrome (TCF4), and Noonan syndrome (PTPN11)). Functional analysis indicated the pathogenicity of theCDKN1Cvariant. The variants we detected inCDKN1CandPLAG1were the second and third variants leading to SRS, respectively. Our patients withCDKN1CandPLAG1variants showed similar phenotypes to previously reported patients. Furthermore, our data confirmedIGF1Rabnormality, SHORT syndrome, and Floating-Harbor syndrome are differential diagnoses of SRS because of the shared phenotypes among these syndromes and SRS. On the other hand, the patients with pathogenic variants in causative genes for Pitt-Hopkins syndrome and Noonan syndrome were atypical of these syndromes and showed partial clinical features of SRS.ConclusionsWe identified nine patients (9.8%) with pathogenic or likely pathogenic variants out of 92 etiology-unknown patients with SRS phenotype. This study expands the molecular spectrum of SRS phenotype.

Additional file 2: Figure S1. File format: PowerPoint. Chromatograms of identified pathogenic or likely pathogenic variants. Arrows indicate mutated nucleotides.

Context Maternal uniparental disomy for chromosome 20 [UPD(20)mat], resulting in aberrant expression of imprinted transcripts at the GNAS locus, is a poorly characterized condition. These patients manifested a phenotype similar to that of Silver-Russell syndrome (SRS) and small for gestational age-short stature (SGA-SS); however, the etiological relationship between UPD(20)mat and SRS/SGA-SS remains unclear. Moreover, no report has described endocrinological assessment of UPD(20)mat patients, although paternal UPD(20), the mirror image entity of UPD(20)mat, is known to cause multiple hormone resistance reflecting reduced α-subunit of the stimulatory G protein expression. Participants Patients 1 to 5 showed nonmosaic heterodisomy and/or isodisomy for the entire chromosome 20. Patients 1 to 3 and 4 were identified through UPD(20)mat screening for 55 patients with etiology-unknown SRS and 96 patients with SGA-SS, respectively. Patient 5 was identified through molecular analysis for patients with developmental defects. Patients 1 to 5 manifested postnatal growth failure and feeding problems, with or without developmental delay, and other clinical features. Patients 1 to 4 were born SGA. Patients 4 and 5 exhibited hypercalcemia and low or low-normal parathyroid hormone levels. Patient 1 showed constantly decreased thyroid-stimulating hormone (TSH) levels after 12 years of age, although she had a normal TSH level at 5.2 years of age. Conclusion The results suggest that UPD(20)mat underlies growth failure and feeding problems with additional features and could account for >5% of etiology-unknown SRS and small percentages of SGA-SS. Most important, this study provides an indication that UPD(20)mat can be associated with hypersensitivity of hormone receptors, which may gradually develop with age.

BackgroundPaternal uniparental disomy for chromosome 7 (upd(7)pat) is extremely rare, and only four cases have been previously reported. As these cases were accompanied by autosomal-recessive disorders which are likely to be involved in growth restriction, the relevance of upd(7)pat to the overgrowth phenotype remains unclear. Here we describe one case of upd(7)pat with no additional genetic diseases, which may answer the question.MethodsA 5-year-old Japanese boy presented with a tall stature of unknown causes. To detect the genetic cause of the tall stature, we performed Sanger sequencing, targeted resequencing, comparative genomic hybridisation and single-nucleotide polymorphism (SNP) array analyses, methylation analysis and microsatellite analysis.ResultsWe could not detect pathogenic variants in causative genes for overgrowth syndrome or apparent copy number alterations. DNA methylation analysis revealed hypomethylation at the GRB10, PEG1 and PEG10 differentially methylated regions. SNP array and microsatellite analyses suggested paternal uniparental isodisomy for chromosome 7. Furthermore, we could not identify homozygous mutations of known causative genes for inherited disorders on chromosome 7.ConclusionWe report the first case of upd(7)pat with an overgrowth phenotype.

Background: IGSF1 abnormality causes diverse symptoms, including congenital central hypothyroidism (CCH), prolactin hyposecretion, testicular enlargement and delayed puberty. Case presentation: Here, we report a case of a male patient who visited our hospital with a chief complaint of abdominal pain and short stature, in whom we identified a novel IGSF1 mutation. He was closely examined because of chronic constipation since infancy, persistent abdominal pain at 14 years of age and marked short stature (−4.7 standard deviation [SD] for normal Japanese boys). He was diagnosed with CCH. Decreased prolactin (PRL) secretion was also observed. IGSF1 analysis revealed a novel mutation at the splicing donor site (c.2065+1G>A) in intron 11. In silico analysis predicted this mutation to be a non-functional splice donor site. After thyroid hormone replacement, his thyroid function, constipation and growth rate improved. Conclusions: This is the first report of a patient in whom constipation and short stature led to a diagnosis of CCH with a novel IGSF1 mutation.

The predominant symptoms of trisomy 14 mosaicism are prenatal and postnatal growth failure, ear abnormalities, congenital heart disease, developmental delay, and genitourinary abnormalities. Maternal uniparental disomy of chromosome 14 (upd(14)mat) presents discernible clinical features such as prenatal and postnatal growth failure, hypotonia, precocious puberty, and obesity. Given the small number of previously reported patients with a combination of trisomy 14 mosaicism and upd(14)mat, the detailed clinical features of these patients remain to be elucidated. Here we report a severely short-statured girl with feeding difficulties and failure to thrive, ear abnormalities, deafness, small hands, and developmental delay. Karyotyping, FISH analysis, methylation analysis, and microsatellite marker analysis using her leukocytes and buccal cells showed that she had a combination of trisomy 14 mosaicism and upd(14)mat. Furthermore, a comparison of the clinical features of this patient with those of previously reported patients with genetic anomalies including the combination of trisomy 14 mosaicism and upd(14)mat or upd(14)mat suggested that the severe short stature observed in patients with a combination of trisomy 14 mosaicism and upd(14)mat stemmed from the synergic effect of these two events. In severely short-statured patients with trisomy 14 mosaicism, we should be aware of the possible coexistence of upd(14)mat.

Context: Pseudohypoparathyroidism type I (PHP-I) is divided into PHP-Ia with Albright hereditary osteodystrophy and PHP-Ib, which usually shows no Albright hereditary osteodystrophy features. Although PHP-Ia and PHP-Ib are typically caused by genetic defects involving α subunit of the stimulatory G protein (Gsα)–coding GNAS exons and methylation defects of the GNAS differentially methylated regions (DMRs) on the maternal allele, respectively, detailed phenotypic characteristics still remains to be examined. Objective: To clarify phenotypic characteristics according to underlying (epi)genetic causes. Patients and Methods: We performed (epi)genotype-phenotype analysis in 69 Japanese patients with PHP-I; that is, 28 patients with genetic defects involving Gsα-coding GNAS exons (group 1) consisting of 12 patients with missense variants (subgroup A) and 16 patients with null variants (subgroup B), as well as 41 patients with methylation defects (group 2) consisting of 21 patients with broad methylation defects of the GNAS-DMRs (subgroup C) and 20 patients with an isolated A/B-DMR methylation defect accompanied by the common STX16 microdeletion (subgroup D). Results: Although (epi)genotype-phenotype findings were grossly similar to those reported previously, several important findings were identified, including younger age at hypocalcemic symptoms and higher frequencies of hyperphosphatemia in subgroup C than in subgroup D, development of brachydactyly in four patients of subgroup C, predominant manifestation of subcutaneous ossification in subgroup B, higher frequency of thyrotropin resistance in group 1 than in group 2, and relatively low thyrotropin values in four patients with low T4 values and relatively low luteinizing hormone/follicle-stimulating hormone values in five adult females with ovarian dysfunction. Conclusion: The results imply the presence of clinical findings characteristic of each underlying cause and provide useful information on the imprinting status of Gsα., (Epi)genotype-phenotype analysis in 69 Japanese patients with pseudohypoparathyroidism type I indicates the presence of clinical findings characteristic of each underlying cause.

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.

Purpose Temple syndrome (TS14) is a rare imprinting disorder caused by aberrations at the 14q32.2 imprinted region. Here, we report comprehensive molecular and clinical findings in 32 Japanese patients with TS14. Methods We performed molecular studies for TS14 in 356 patients with variable phenotypes, and clinical studies in all TS14 patients, including 13 previously reported. Results We identified 19 new patients with TS14, and the total of 32 patients was made up of 23 patients with maternal uniparental disomy (UPD(14)mat), six patients with epimutations, and three patients with microdeletions. Clinical studies revealed both Prader-Willi syndrome (PWS)-like marked hypotonia and Silver-Russell syndrome (SRS)-like phenotype in 50% of patients, PWS-like hypotonia alone in 20% of patients, SRS-like phenotype alone in 20% of patients, and nonsyndromic growth failure in the remaining 10% of patients in infancy, and gonadotropin-dependent precocious puberty in 76% of patients who were pubescent or older. Conclusion These results suggest that TS14 is not only a genetically diagnosed entity but also a clinically recognizable disorder. Genetic testing for TS14 should be considered in patients with growth failure plus both PWS-like hypotonia and SRS-like phenotypes in infancy, and/or precocious puberty, as well as a familial history of Kagami-Ogata syndrome due to maternal microdeletion at 14q32.2.

Background Wolfram syndrome (WS) is a disorder characterized by the association of insulin-dependent diabetes mellitus (DM), diabetes insipidus, deafness, and optic nerve atrophy. WS is caused by WFS1 mutations encoding WFS1 protein expressed in endoplasmic reticulum (ER). During ER protein synthesis, misfolded and unfolded proteins accumulate, known as “ER stress”. This is attenuated by the unfolded protein response (UPR), which recovers and maintains ER functions. Because WFS1 is a UPR component, mutant WFS1 might cause unresolvable ER stress conditions and cell apoptosis, the major causes underlying WS symptoms. We encountered an 11-month-old Japanese female WS patient with insulin-dependent DM, congenital cataract and severe bilateral hearing loss. Objective Analyze the WFS1 and functional consequence of the patient WFS1 in vitro. Results The patient WFS1 contained a heterozygous 4 amino acid in-frame deletion (p.N325_I328del). Her mutant WFS1 increased GRP78 and ATF6α promoter activities in the absence of thapsigargin, indicating constitutive ER stress and nuclear factor of activated T-cell reporter activity, reflecting elevated cytosolic Ca2+ signals. Mutant transfection into cells reduced mRNA expression levels of sarcoplasmic/endoplasmic reticulum Ca2+ transport ATPase 2b (SERCA2b) compared with wild type. Because SERCA2b is required for ER and cytoplasmic Ca2+ homeostasis, decreased SERCA2b expression might affect ER Ca2+ efflux, causing cell apoptosis. Conclusion A novel heterozygous mutation of WFS1 induced constitutive ER stress through ATF6α activation and ER Ca2+ efflux, resulting in cell apoptosis. These results provide new insights into the roles of WFS1 in UPR and mechanism of monogenic DM.

Hypogonadotropic hypogonadism (HH) is a genetically heterogeneous condition that occurs either as an isolated disorder or as a component of congenital malformation syndromes. SOX2 is a causative gene of syndromic HH characterized by anophthalmia, microphthalmia, or coloboma and other neurological defects such as epilepsy. To date, the causal relationship between SOX2 abnormalities and non-syndromic HH remains speculative. Here, we identified a nonsense mutation of SOX2 in a male patient clinically diagnosed with non-syndromic HH. The patient had epilepsy but no additional clinical features. Ophthalmological examination revealed no abnormalities except for decreased thickness of the retinal nerve fiber layer. Audiometry showed mild sensorineural hearing impairment of both ears. Hormonal evaluation suggested isolated gonadotropin deficiency. Next-generation sequencing-based mutation screening of 13 major causative genes for HH identified a p.Lys35∗ mutation in SOX2 and excluded pathogenic mutations in other tested genes. The p.Lys35∗ mutation appeared to encode a non-functioning SOX2 protein that lacks 283 of 317 amino acids. The SOX2 mutation was absent in the maternal DNA sample, while a paternal sample was unavailable for sequence analysis. These results expand the clinical consequences of SOX2 haploinsufficiency to include non-syndromic HH. Systematic mutation screening using a next-generation sequencer and detailed evaluation of nonspecific ocular/neurological features may help identify SOX2 mutation-positive individuals among HH patients.

Pseudohypoaldosteronism (PHA) type 1 is a disease showing mineralocorticoid resistance in the kidney and/or other mineralocorticoid target tissues. Patients with PHA1 present very high plasma aldosterone and renin levels, but they develop excessive salt wasting. There are three types of PHA1. The systemic form of PHA1 is inherited in an autosomal recessive manner and causes severe life-long salt loss in multiple target tissues, such as sweat glands, salivary glands, the colonic epithelium, and the lung. In the systemic form of PHA1, life-long salt supplementation is necessary. The second type is the renal form, where aldosterone resistance is shown only in the kidney, and its inheritance is autosomal dominant. In the renal form of PHA1, salt supplementation generally becomes unnecessary by 1–3 yr of age. The third type is the secondary PHA1, which is strongly associated with urinary tract infections and/or urinary tract malformations. This review summarizes the clinical features and molecular basis of PHA1. Understanding of its pathogenesis can be helpful for the early diagnosis and clinical care of affected children with PHA1.

Although mutations in ACAN, FGFR3, NPR2, and SHOX typically lead to skeletal dysplasia, and mutations in GHRHR, GH1, GHR, STAT5B, IGF1, IGFALS, and IGF1R usually underlie hormonal defects of the growth hormone (GH)-insulin-like growth factor 1 (IGF1) axis, such mutations have also been identified in patients with idiopathic short stature (ISS). Of these, SHOX abnormalities are known to account for a certain percentage of ISS cases, whereas the frequency of mutations in the other 10 genes in ISS cohorts remains unknown. Here, we performed next-generation sequencing-based mutation screening of the 10 genes in 86 unrelated Japanese ISS patients without SHOX abnormalities. We searched for rare protein-altering variants. The functional significance of the identified variants was assessed by in silico analyses. Consequently, we identified 18 heterozygous rare variants in 19 patients, including four probable damaging variants in ACAN, six pathogenicity-unknown variants in FGFR3, GHRHR, GHR, and IGFALS, and eight possible benign variants. Pathogenic variants in NPR2, GH1, and IGF1 were absent from our cohort. Unlike previously reported patients with ACAN mutations, our four patients with ACAN variants manifested non-specific short stature with age-appropriate or mildly delayed bone ages, and had parents of normal stature. These results indicate that ACAN mutations can underlie ISS without characteristic skeletal features, and that such mutations are possibly associated with de novo occurrence or low penetrance. In addition, our data imply that mutations in FGFR3, NPR2, and GH-IGF1 axis genes play only limited roles in the etiology of ISS.

Purpose Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder; however, its molecular etiology remains poorly understood. Methods We performed genetic analysis of 24 causative genes using next-generation sequencing in 167 CH cases, comprising 57 dyshormonogenesis (DH), 32 dysgenesis (TD) and 78 undiagnosed. The pathogenicity of variants was assessed by the American College of Medical Genetics guidelines, inheritance pattern, and published evidence. Furthermore, we compared the oligogenic groups and monogenic groups to examine the correlation between variant dosage and severity. Results We identified variants in 66.5% cases (111/167) and 15 genes, DUOX2, TSHR, PAX8, TG, TPO, DUOXA2, JAG1, GLIS3, DUOX1, IYD, SLC26A4, SLC5A5, SECISBP2, DIO1, and DIO3. Biallelic variants were identified in 12.6% (21/167), oligogenic in 18.0% (30/167), and monogenic in 35.9% (60/167); however, 68.5% of variants were classified as variant of unknown significance (VUS). Further examinations showed that 3 out of 32 cases with TD (9.4%) had pathogenic variants (2 of TSHR and 1 of TPO), and 8 out of 57 cases with DH (14.0%) (7 of DUOX2, 1 of TG) had pathogenic variants. In addition, TSH levels at the first visit were significantly higher in the oligogenic group than in the monogenic group. Conclusions The detection rate of pathogenic variants in Japanese CH was similar to that previously reported. Moreover, oligogenic cases were likely to be more severe than monogenic cases, suggesting that CH may exhibit a gene dosage effect. Further analysis of VUS pathogenicity is required to clarify the molecular basis of CH.