scholarly journals Three patients with defects in interferon gamma receptor signaling: a challenging diagnosis

Author(s):  
Zijun Zhou ◽  
Iris Hollink ◽  
Arjan Bouman ◽  
Mirthe Lourens ◽  
Rik Brooimans ◽  
...  

Background: Defects in IFN–gamma receptor (IFN-γR) signaling via STAT1 leads to susceptibility to infection by otherwise weak pathogenic mycobacteria, resulting in mendelian susceptibility to mycobacterial disease. We identified three patients presented with disseminated mycobacterial infections caused by M. avium, M. persicum or M. bovis BCG respectively. Whole-exome sequencing (WES) was used as the first line diagnostic approach, however in all patients additional analysis was crucial to make the definite diagnosis. Method: WES, SNP array and long range PCR were performed to identify the genetic defects. Expression of IFNGR1, STAT1, CD64, SOCS1 and phosphorylation of STAT1 were determined after stimulation with IFN-α or IFN-γ. Results: In Patient 1, only one heterozygous variant p.(Val63Gly) in the IFNGR1 gene was identified by WES. Additional genetic analysis identified a second complex Alu-insertion in IFNGR1. Patient 2 was compound heterozygous for the null p.(Val68Lysfs*6) variant and the hypomorphic p.(Ile37Thr) variant in IFNGR1. In Patient 3 a novel variant in the STAT1 gene p.(Asn460Ile) was identified. Patients 1 and 2 had reduced expression of IFN-γR1. All patients had reduced phosphorylation of STAT1 and absent induction of SOCS1 after IFN-γ stimulation. While STAT1 phosphorylation was normal after IFN–α stimulation in Patient 1 and 2, and mildly reduced in Patient 3. Conclusion: We conclude that functional assays are crucial to assess the extent of IFN-γR signaling defects when new combinations of bi-allelic or non-conclusive genetic variants are found, which is important in the determination of clinical treatment.

2021 ◽  
Author(s):  
Zijun Zhou ◽  
Iris H.I.M. Hollink ◽  
Arjan Bouman ◽  
Mirthe S. Lourens ◽  
Rik A. Brooimans ◽  
...  

Abstract IFN–gamma receptor (IFNGR) signaling via STAT1 is crucial in the defense against intracellular pathogens. Defects in this pathway enhance the susceptibility to infection by otherwise weak pathogenic mycobacteria, resulting in a primary immunodeficiency called mendelian susceptibility to mycobacterial disease (MSMD). Here we describe three patients with MSMD caused by variants in the IFNGR1 or STAT1 genes. All three patients presented with disseminated non-tuberculous mycobacterial infections caused by M. avium , M. persicum or M. bovis BCG respectively. Whole-exome sequencing (WES) was used as the first line diagnostic approach, however in all patients additional analysis was crucial to make the definite diagnosis. In Patient 1, only one heterozygous autosomal recessive variant p.(Val63Gly) in the IFNGR1 gene was identified. Patient 2 was compound heterozygous for the pathogenic null p.(Val68Lysfs*6) variant and the hypomorphic p.(Ile37Thr) variant in IFNGR1. In Patient 3 a novel variant in the STAT1 gene c.1379A>T, p.(Asn460Ile) was identified. Additional genetic analysis identified a second novel complex Alu-insertion in the IFNGR1 gene in Patient 1. Functional analysis showed that Patients 1 and 2 had reduced expression of IFNGR1. All patients had reduced phosphorylation of STAT1 and absent induction of SOCS1 mRNA after IFN-γ stimulation. While STAT1 phosphorylation was normal after IFN–α stimulation in Patient 1 and 2, it was mildly reduced in Patient 3. We conclude that functional assays are crucial to assess the extent of IFNGR signaling defects when new combinations of bi-allelic or non-conclusive genetic variants are found, which is important in the determination of clinical treatment.


Author(s):  
Zhidan Hong ◽  
Xuanyi He ◽  
Fang Yu ◽  
Huanyu Liu ◽  
Xiaoli Zhang ◽  
...  

AbstractMeckel-Gruber syndrome (MKS) is a rare lethal autosomal recessive inherited disorder. Missed diagnosis might happen in clinical works due to an unclear genotype–phenotype correlation. We analyzed two families visiting our center; the parents are normal; each of the family aborted a fetus at 12WG. Following ultrasonography and pathological examination, both were diagnosed as MKS. Whole exome sequencing identified a compound heterozygous of two novel variants of CEP290 and a heterozygous of a novel variant of CC2D2A. Frameshift mutations in ZNF77 were also detected. Western blot analyzing whole-brain tissue showed that the expression of ZNF77, CC2D2A, and CEP290 was enhanced. HEK293T transfected with over-expression wildtype/mutated ZNF77 plasmid showed that SHH was increased in wildtype ZNF77 cells, while SHH and CC2D2A were increased in mutated ZNF77 cells. Our research provided two novel pathogenic variants of CEP290 and CC2D2A and suggested that ZNF77 might promote the expression of CC2D2A and regulate the amount of SHH.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Jong Seop Kim ◽  
Hyoungseok Jeon ◽  
Hyeran Lee ◽  
Jung Min Ko ◽  
Yonghwan Kim ◽  
...  

AbstractAn 11-year-old Korean boy presented with short stature, hip dysplasia, radial head dislocation, carpal coalition, genu valgum, and fixed patellar dislocation and was clinically diagnosed with Steel syndrome. Scrutinizing the trio whole-exome sequencing data revealed novel compound heterozygous mutations of COL27A1 (c.[4229_4233dup]; [3718_5436del], p.[Gly1412Argfs*157];[Gly1240_Lys1812del]) in the proband, which were inherited from heterozygous parents. The maternal mutation was a large deletion encompassing exons 38–60, which was challenging to detect.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Dongdong Tang ◽  
Yanwei Sha ◽  
Yang Gao ◽  
Jingjing Zhang ◽  
Huiru Cheng ◽  
...  

Abstract Background Asthenozoospermia is one of the most common causes of male infertility, and its genetic etiology is poorly understood. DNAH9 is a core component of outer dynein arms in cilia and flagellum. It was reported that variants of DNAH9 (OMIM: 603330) might cause primary ciliary dyskinesia (PCD). However, variants in DNAH9 lead to nonsyndromic severe asthenozoospermia have yet to be reported. Methods Whole exome sequencing (WES) was performed for two individuals with nonsyndromic severe asthenozoospermia from two non-consanguineous families, and Sanger sequencing was performed to verify the identified variants and parental origins. Sperm routine analysis, sperm vitality rate and sperm morphology analysis were performed according the WHO guidelines 2010 (5th edition). Transmission electron microscopy (TEM, TECNAI-10, 80 kV, Philips, Holland) was used to observe ultrastructures of sperm tail. Quantitative realtime-PCR and immunofluorescence staining were performed to detect the expression of DNAH9-mRNA and location of DNAH9-protein. Furthermore, assisted reproductive procedures were applied. Results By WES and Sanger sequencing, compound heterozygous DNAH9 (NM_001372.4) variants were identified in the two individuals with nonsyndromic severe asthenozoospermia (F1 II-1: c.302dupT, p.Leu101fs*47 / c.6956A > G, p.Asp2319Gly; F2 II-1: c.6294 T > A, p.Phe2098Leu / c.10571 T > A, p.Leu3524Gln). Progressive rates less than 1% with normal sperm morphology rates and normal vitality rates were found in both of the two subjects. No respiratory phenotypes, situs inversus or other malformations were found by detailed medical history, physical examination and lung CT scans etc. Moreover, the expression of DNAH9-mRNA was significantly decreased in sperm from F1 II-1. And expression of DNAH9 is lower in sperm tail by immunofluorescence staining in F1 II-1 compared with normal control. Notably, by intracytoplasmic sperm injection (ICSI), F1 II-1 and his partner successfully achieved clinical pregnancy. Conclusions We identified DNAH9 as a novel pathogenic gene for nonsyndromic severe asthenospermia, and ICSI can contribute to favorable pregnancy outcomes for these patients.


2021 ◽  
Vol 22 (7) ◽  
pp. 3625
Author(s):  
Filomena Napolitano ◽  
Giorgia Bruno ◽  
Chiara Terracciano ◽  
Giuseppina Franzese ◽  
Nicole Piera Palomba ◽  
...  

Pompe disease is an autosomal recessive disorder caused by a deficiency in the enzyme acid alpha-glucosidase. The late-onset form of Pompe disease (LOPD) is characterized by a slowly progressing proximal muscle weakness, often involving respiratory muscles. In LOPD, the levels of GAA enzyme activity and the severity of the clinical pictures may be highly variable among individuals, even in those who harbour the same combination of GAA mutations. The result is an unpredictable genotype–phenotype correlation. The purpose of this study was to identify the genetic factors responsible for the progression, severity and drug response in LOPD. We report here on a detailed clinical, morphological and genetic study, including a whole exome sequencing (WES) analysis of 11 adult LOPD siblings belonging to two Italian families carrying compound heterozygous GAA mutations. We disclosed a heterogeneous pattern of myopathic impairment, associated, among others, with cardiac defects, intracranial vessels abnormality, osteoporosis, vitamin D deficiency, obesity and adverse response to enzyme replacement therapy (ERT). We identified deleterious variants in the genes involved in autophagy, immunity and bone metabolism, which contributed to the severity of the clinical symptoms observed in the LOPD patients. This study emphasizes the multisystem nature of LOPD and highlights the polygenic nature of the complex phenotype disclosed in these patients.


2017 ◽  
Vol 60 (12) ◽  
pp. 635-638 ◽  
Author(s):  
Ryojun Takeda ◽  
Masaki Takagi ◽  
Hiroyuki Shinohara ◽  
Hiroshi Futagawa ◽  
Satoshi Narumi ◽  
...  

2021 ◽  
Vol 9 ◽  
Author(s):  
Lingxia Zhang ◽  
Ke Huang ◽  
Shugang Wang ◽  
Haidong Fu ◽  
Jingjing Wang ◽  
...  

Gitelman syndrome (GS, OMIM 263800) is a genetic congenital tubulopathy associated with salt loss, which is characterized by hypokalemic metabolic toxicity, hypocalciuria, and hypomagnesemia. GS, which is typically detected in adolescence or adulthood, has long been considered a benign tubular lesion; however, the disease is associated with a significant decrease in the quality of life. In this study, we assessed the genotype–phenotype correlations based on the medical histories, clinical symptoms, laboratory test results, and whole-exome sequencing profiles from pediatric patients with GS. Between January 2014 and December 2020, all 31 consecutively enrolled patients complained of fatigue, salt craving, and muscle weakness. Sixteen patients demonstrated growth retardation, and five patients presented with nocturia and constipation. All patients presented with hypokalemic metabolic alkalosis, normal blood pressure, hyperaldosteronism, and a preserved glomerular filtration rate, and 24 of the 31 (77.4%) patients had hypomagnesemia. Homozygous, compound heterozygous, and heterozygous mutations in SLC12A3 were detected in 4, 24, and 3 patients, respectively. GS patients often present with muscle weakness and fatigue caused by hypokalemia and hypomagnesemia. Therefore, early diagnosis of GS is important in young children to reduce the possibility of growth retardation, tetany, and seizures. Next-generation sequencing such as whole-exome or whole-genome sequencing provides a practical tool for the early diagnosis and improvement of GS prognosis. Further whole-genome sequencing is expected to reveal more variants in SLC123A among GS patients with single heterozygous mutations.


2021 ◽  
Author(s):  
Min Li ◽  
Weisheng Li ◽  
Dan Zhu ◽  
Likui Lu ◽  
Jingliu Liu ◽  
...  

Abstract Background: Kindler syndrome (KNDLRS) is a very rare autosomal recessive disorder characterized by bullous poikiloderma with photosensitivity. Loss-of-function mutations in FERMT1, which located on chromosome 20p12.3, were responsible for KNDLRS. Numerous mutations in FERMT1 have been reported to be associated with KNDLRS. Results: The present study reported two Chinese KNDLRS families, and affected individuals from both families presented with poikiloderma, palmoplantar hyperkeratosis, and diffuse cigarette paper like atrophy on hands. Skin biopsy of the proband from family 2 showed atrophy of epidermis, hyperkeratosis, dilated blood vessels in upper dermis, and microbubbles at the dermis and epidermis junction. Medical Whole Exome Sequencing V4 combined with Sanger sequencing revealed mutations in FERMT1 with affected individuals. Compound heterozygous nonsense mutations (c.193C>T, c.277C>T) were found with family 1, and a homozygous frameshift mutation (c.220delC) was observed in family 2. According to the clinical features and genetic analysis, KNDLRS was diagnosed in two Chinese families. Conclusions: This study revealed two novel pathogenic mutations in FERMT1 that caused KNDLRS and briefly summarized all pathogenic mutations in FERMT1 that have been documented via the PubMed.


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