scholarly journals Genetic characteristics of retinitis pigmentosa in 1204 Japanese patients

2019 ◽  
Vol 56 (10) ◽  
pp. 662-670 ◽  
Author(s):  
Yoshito Koyanagi ◽  
Masato Akiyama ◽  
Koji M Nishiguchi ◽  
Yukihide Momozawa ◽  
Yoichiro Kamatani ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Japanese Population ◽  
East Asian ◽  
Japanese Patients ◽  
Population Based ◽  
Genetic Profile ◽  
Genetic Characteristics ◽  
Pathogenic Variants ◽  
Recessive Genes ◽  
Dominant Genes

BackgroundThe genetic profile of retinitis pigmentosa (RP) in East Asian populations has not been well characterised. Therefore, we conducted a large-scale sequencing study to investigate the genes and variants causing RP in a Japanese population.MethodsA total of 1209 Japanese patients diagnosed with typical RP were enrolled. We performed deep resequencing of 83 known causative genes of RP using next-generation sequencing. We defined pathogenic variants as those that were putatively deleterious or registered as pathogenic in the Human Gene Mutation Database or ClinVar database and had a minor allele frequency in any ethnic population of ≤0.5% for recessive genes or ≤0.01% for dominant genes as determined using population-based databases.ResultsWe successfully sequenced 1204 patients with RP and determined 200 pathogenic variants in 38 genes as the cause of RP in 356 patients (29.6%). Variants in six genes (EYS, USH2A, RP1L1, RHO, RP1 and RPGR) caused RP in 65.4% (233/356) of those patients. Among autosomal recessive genes, two known founder variants in EYS [p.(Ser1653fs) and p.(Tyr2935*)] and four East Asian-specific variants [p.(Gly2752Arg) in USH2A, p.(Arg658*) in RP1L1, p.(Gly2186Glu) in EYS and p.(Ile535Asn) in PDE6B] and p.(Cys934Trp) in USH2A were found in ≥10 patients. Among autosomal dominant genes, four pathogenic variants [p.(Pro347Leu) in RHO, p.(Arg872fs) in RP1, p.(Arg41Trp) in CRX and p.(Gly381fs) in PRPF31] were found in ≥4 patients, while these variants were unreported or extremely rare in both East Asian and non-East Asian population-based databases.ConclusionsEast Asian-specific variants in causative genes were the major causes of RP in the Japanese population.

Clinical and genetic investigation of 136 Japanese patients with congenital hypothyroidism

2020 ◽  
Vol 33 (6) ◽  
pp. 691-701 ◽  
Author(s):  
Tatsushi Tanaka ◽  
Kohei Aoyama ◽  
Atsushi Suzuki ◽  
Shinji Saitoh ◽  
Haruo Mizuno
Keyword(s):  
Congenital Hypothyroidism ◽  
Molecular Genetic ◽  
Genetic Diagnosis ◽  
Japanese Patients ◽  
Thyroid Stimulating Hormone ◽  
Allelic Variant ◽  
Genetic Investigation ◽  
Pathogenic Variants ◽  
Recessive Genes ◽  
Molecular Genetic Diagnosis

AbstractObjectivesCongenital hypothyroidism (CH) is the most common congenital endocrine disorder. Recent advances in genetic testing have revealed its causative mutations in some CH patients. However, the underlying etiology remains unknown in most patients. This study aimed to perform clinical and genetic investigation in Japanese CH patients to uncover genotype-phenotype correlations.MethodsWe enrolled 136 Japanese patients with transient or permanent CH between April 2015 and March 2017, and performed next-generation sequencing of 19 genes implicated in CH.ResultsWe identified potentially pathogenic bi-allelic variants in DUOX2, TSHR, and TPO in 19, 5, and 1 patient, respectively (autosomal recessive), and a potentially pathogenic mono-allelic variant in NKX2-1 (autosomal dominant) in 1 patient. Molecular genetic diagnosis was highly suggested in 26 patients (19%) from 23 families. We also detected a potentially pathogenic mono-allelic variant in five recessive genes (DUOX2, TSHR, TG, DUOXA2, and TPO) in 31 unrelated patients (23%), although the pathogenicity of these variants remains inconclusive. Patients with bi-allelic DUOX2 variants showed a more severe clinical presentation in infancy than those with bi-allelic TSHR variants. However, this trend reversed beyond infancy. There were no statistical differences in initial thyroid stimulating hormone, free thyroxine, thyroglobulin, and levothyroxine dose as of March 2017 between patients with bi-allelic and mono-allelic DUOX2 variants.ConclusionsThe prevalence of potentially-pathogenic variants in Japanese CH patients was similar to that found by previous reports. Our study demonstrates a genotype-phenotype correlation in Japanese CH patients.

scholarly journals Genetic profiles of Barrett’s esophagus and esophageal adenocarcinoma in Japanese patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mamoru Tokunaga ◽  
Kenichiro Okimoto ◽  
Naoki Akizue ◽  
Kentaro Ishikawa ◽  
Yosuke Hirotsu ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Esophageal Adenocarcinoma ◽  
Barrett's Esophagus ◽  
Medical Information ◽  
Japanese Patients ◽  
Endoscopic Biopsy ◽  
University Hospital ◽  
Genetic Profile ◽  
Genetic Characteristics ◽  
Significant Difference

AbstractThe genetic characteristics of Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC) in the Japanese population is unclear. This study aims to investigate the genetic characteristics from nondysplastic BE (NDBE) to early EAC in Japan. Clinical information was collected. Moreover, the genetic profile of NDBE without concurrent dysplasia, early EAC, and surrounding BE were also investigated using endoscopic biopsy samples and formalin-fixed, paraffin-embedded specimens from Japanese patients by targeted next-generation sequencing. Immunohistochemical staining for p53 was also performed for EAC lesions. Targeted NGS was performed for 33 cases with 77 specimens. No significant difference exists in the NDBE group between the number of putative drivers per lesion in the short-segment Barrett’s esophagus (SSBE) and long-segment Barrett’s esophagus (LSBE) [0 (range, 0–1) vs. 0 (range, 0–1). p = 1.00]. TP53 putative drivers were found in two patients (16.7%) with nondysplastic SSBE. TP53 was the majority of putative drivers in both BE adjacent to EAC and EAC, accounting for 66.7% and 66.7%, respectively. More putative drivers per lesion were found in the EAC than in the NDBE group [1 (range, 0–3) vs. 0 (range, 0–1). p < 0.01]. The genetic variants of TP53 in the Japanese early EAC were similar to those in western countries. However, TP53 putative drivers were detected even in Japanese patients with nondysplastic SSBE. This is significant because such nondysplastic SSBE might have higher risk of progressing to high-grade dysplasia or EAC. The risks of progression may not be underestimated and appropriate follow-ups may be necessary even in patients with SSBE.Trial registration: This study was registered at the University Hospital Medical Information Network (UMIN000034247).

scholarly journals Truncating Variants Contribute to Hearing Loss and Severe Retinopathy in USH2A-Associated Retinitis Pigmentosa in Japanese Patients

2020 ◽  
Vol 21 (21) ◽  
pp. 7817
Author(s):  
Akira Inaba ◽  
Akiko Maeda ◽  
Akiko Yoshida ◽  
Kanako Kawai ◽  
Yasuhiko Hirami ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Usher Syndrome ◽  
Japanese Patients ◽  
Genetic Alterations ◽  
Causal Gene ◽  
Phenotype Correlation ◽  
Pathogenic Variants ◽  
Genetic Features ◽  
Tissue Damages

USH2A is a common causal gene of retinitis pigmentosa (RP), a progressive blinding disease due to retinal degeneration. Genetic alterations in USH2A can lead to two types of RP, non-syndromic and syndromic RP, which is called Usher syndrome, with impairments of vision and hearing. The complexity of the genotype–phenotype correlation in USH2A-associated RP (USH2A-RP) has been reported. Genetic and clinical characterization of USH2A-RP has not been performed in Japanese patients. In this study, genetic analyses were performed using targeted panel sequencing in 525 Japanese RP patients. Pathogenic variants of USH2A were identified in 36 of 525 (6.9%) patients and genetic features of USH2A-RP were characterized. Among 36 patients with USH2A-RP, 11 patients had syndromic RP with congenital hearing problems. Amino acid changes due to USH2A alterations were similarly located throughout entire regions of the USH2A protein structure in non-syndromic and syndromic RP cases. Notably, truncating variants were detected in all syndromic patients with a more severe retinal phenotype as compared to non-syndromic RP cases. Taken together, truncating variants could contribute to more serious functional and tissue damages in Japanese patients, suggesting important roles for truncating mutations in the pathogenesis of syndromic USH2A-RP.

Prevalence and Spectrum of Pathogenic Germline Variants in Japanese Patients With Early-Onset Colorectal, Breast, and Prostate Cancer

2020 ◽  
pp. 183-191 ◽  
Author(s):  
Xiaoxi Liu ◽  
Sadaaki Takata ◽  
Kyota Ashikawa ◽  
Tomomi Aoi ◽  
Shunichi Kosugi ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Dna Repair ◽  
Early Onset ◽  
Japanese Population ◽  
Japanese Patients ◽  
Cancer Type ◽  
Cancer Gene ◽  
Germline Variants ◽  
Pathogenic Variants ◽  
Second Tier

PUPOSE We investigated the prevalence and spectrum of pathogenic germline variants in patients with early-onset colorectal cancer (CRC), breast cancer (BC), and prostate cancer (PCA) in the Japanese population. We also identified pathogenic variants in other cancer risk genes, giving consideration to future multigene testing panels for this population. METHODS We performed whole-genome sequencing for 1,037 Japanese individuals, including patients with early-onset CRC (n = 196), BC (n = 237), and PCA (n = 215) and controls (n = 389). We screened for pathogenic variants, including single nucleotide variants and copy number variants, among well-established first-tier cancer genes for each cancer type and examined an expended second-tier panel including cancer-predisposing genes from the Cancer Gene Census. RESULTS Proportions of patients with germline pathogenic variants differed by cancer subgroup, with the highest in BC (14.8%), followed by CRC (9.2%), and PCA (3.7%). In contrast, 2 of 389 control subjects (0.5%) carried a germline pathogenic variant. In comparison with controls, the proportion of patients with pathogenic variants in the second-tier panel was increased significantly for PCA (3.7% to 11.6%, P = 2.96 × 10−4), but not for CRC or BC, after multitesting adjustment. In patients with PCA, DNA repair pathway genes in the extended panel often contained pathogenic variants ( P = .011). CONCLUSION Our analyses support the clinical usefulness of established cancer gene panels in the Japanese population for 3 major cancer types. Additional genes, especially those involved in DNA repair, might be considered for developing multipanel testing in Japanese patients with early-onset PCA.

scholarly journals Genetic and Phenotypic Landscape of PRPH2-Associated Retinal Dystrophy in Japan

Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1817
Author(s):  
Akio Oishi ◽  
Kaoru Fujinami ◽  
Go Mawatari ◽  
Nobuhisa Naoi ◽  
Yasuhiro Ikeda ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Age Of Onset ◽  
Phenotypic Variability ◽  
Retinal Dystrophy ◽  
Japanese Patients ◽  
Macular Dystrophy ◽  
Hand Motion ◽  
Pathogenic Variants ◽  
Inherited Retinal Dystrophy ◽  
Asian Cohort

Peripherin-2 (PRPH2) is one of the causative genes of inherited retinal dystrophy. While the gene is relatively common in Caucasians, reports from Asian ethnicities are limited. In the present study, we report 40 Japanese patients from 30 families with PRPH2-associated retinal dystrophy. We identified 17 distinct pathogenic or likely pathogenic variants using next-generation sequencing. Variants p.R142W and p.V200E were relatively common in the cohort. The age of onset was generally in the 40’s; however, some patients had earlier onset (age: 5 years). Visual acuity of the patients ranged from hand motion to 1.5 (Snellen equivalent 20/13). The patients showed variable phenotypes such as retinitis pigmentosa, cone-rod dystrophy, and macular dystrophy. Additionally, intrafamilial phenotypic variability was observed. Choroidal neovascularization was observed in three eyes of two patients with retinitis pigmentosa. The results demonstrate the genotypic and phenotypic variations of the disease in the Asian cohort.

scholarly journals Clinical and genetic characteristics of 14 patients from 13 Japanese families with RPGR-associated retinal disorder: report of eight novel variants

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Go Mawatari ◽  
◽  
Kaoru Fujinami ◽  
Xiao Liu ◽  
Lizhu Yang ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Japanese Population ◽  
Age Of Onset ◽  
Genetic Characteristics ◽  
Therapeutic Trials ◽  
Novel Variants ◽  
Genetic Features ◽  
The Mean ◽  
The Right ◽  
Retinal Disorder

AbstractVariants in the retinitis pigmentosa GTPase regulator (RPGR) gene are a major cause of X-linked inherited retinal disorder (IRD). We herein describe the clinical and genetic features of 14 patients from 13 Japanese families harboring RPGR variants in a nationwide cohort. Comprehensive ophthalmological examinations were performed to classify the patients into one of the phenotype subgroups: retinitis pigmentosa (RP) and cone rod dystrophy (CORD). The mean age of onset/at examination was 13.8/38.1 years (range, 0–50/11–72), respectively. The mean visual acuity in the right/left eye was 0.43/0.43 (range, 0.1–1.7/−0.08–1.52) LogMAR unit. Eight patients had RP, and six had CORD. Whole-exome sequencing with target analyses identified 13 RPGR variants in 730 families with IRD, including 8 novel variants. An association between the phenotype subgroup and the position of variants (cutoff of amino acid 950) was revealed. To conclude, the clinical and genetic spectrum of RPGR-associated retinal disorder was first illustrated in a Japanese population, with a high proportion of novel variants. These results suggest the distinct genetic background of RPGR in the Japanese population, in which the genotype–phenotype association was affirmed. This evidence should be helpful monitoring and counseling patients and in selecting patients for future therapeutic trials.

scholarly journals Genetic Profiles of Barrett’s Esophagus and Esophageal Adenocarcinoma in Japanese patients

2021 ◽  
Author(s):  
Mamoru Tokunaga ◽  
Kenichiro Okimoto ◽  
Naoki Akizue ◽  
Kentaro Ishikawa ◽  
Yosuke Hirotsu ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Esophageal Adenocarcinoma ◽  
Barrett's Esophagus ◽  
Medical Information ◽  
Japanese Patients ◽  
Endoscopic Biopsy ◽  
University Hospital ◽  
Genetic Profile ◽  
Genetic Characteristics ◽  
Significant Difference

Abstract The genetic characteristics of Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC) in the Japanese population is unclear. This study aims to investigate the genetic characteristics from nondysplastic BE (NDBE) to early EAC in Japan. Clinical information was collected. Moreover, the genetic profile of NDBE without concurrent dysplasia, early EAC, and surrounding BE were also investigated using endoscopic biopsy samples and formalin-fixed, paraffin-embedded specimens from Japanese patients by targeted next-generation sequencing. Immunohistochemical staining for p53 was also performed for EAC lesions. Targeted NGS was performed for 33 cases with 77 specimens. No significant difference exists in the NDBE group between the number of putative drivers per lesion in the short-segment Barrett’s esophagus (SSBE) and long-segment Barrett’s esophagus (LSBE) [0 (range, 0–1) vs. 0 (range, 0–1). p = 1.00]. TP53 putative drivers were found in two patients (16.7%) with nondysplastic SSBE. TP53 was the majority of putative drivers in both BE adjacent to EAC and EAC, accounting for 66.7% and 66.7%, respectively. More putative drivers per lesion were found in the EAC than in the NDBE group [1 (range, 0–3) vs. 0 (range, 0–1). p < 0.01]. The genetic variants of early EAC in the Japanese were similar to those in western countries. However, TP53 putative drivers were detected even in Japanese patients with nondysplastic SSBE. The risks of progression may not be underestimated and appropriate follow-ups may be necessary even in patients with SSBE.This study was registered at the University Hospital Medical Information Network (UMIN000034247).

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