CTSC compound heterozygous mutations in two Chinese patients with Papillon–Lefèvre syndrome

Oral Diseases ◽  
2019 ◽  
Vol 25 (5) ◽  
pp. 1394-1402 ◽  
Author(s):  
Yuelin Wu ◽  
Lei Zhao ◽  
Chunmei Xu ◽  
Yafei Wu
Author(s):  
Jiamin Jin ◽  
Xiaomei Tong ◽  
Yin-Li Zhang ◽  
Weijie Yang ◽  
Yerong Ma ◽  
...  

Abstract Purpose To study associations between novel WEE2 mutations and patients with fertilization failure or poor fertilization. Methods Thirty-one Chinese patients who underwent treatment with assisted reproductive technology and suffered from repeated (at least two times) total fertilization failure (TFF) or a low fertilization rate were enrolled. Genomic DNA was extracted from patients for whole-exome sequencing. Suspicious mutations were validated by Sanger sequencing. WEE2 protein levels in oocytes from affected patients were examined by immunofluorescence. Disruptive effects of mutations on WEE2 protein stability, subcellular localization, and kinase function were analyzed through western blotting, immunofluorescence, and flow cytometry in HeLa cells. Results Three of thirty-one (9.6%) enrolled patients had six compound heterozygous mutations of the WEE2 gene, and three of them were reported here for the first time (c.115_116insT, c.756_758delTGA, and c.C1459T). Oocytes from affected patients showed decreased WEE2 immunofluorescence signals. In vitro experiments showed that the mutant WEE2 gene caused reduced WEE2 protein levels or cellular compartment translocation in HeLa cells, leading to decreased levels of the phosphorylated Cdc2 protein. Compared with the wild-type WEE2 protein, the mutant WEE2 proteins were also found to have different effects on the cell cycle. Conclusion Three novel compound heterozygous WEE2 variants were found in patients with pronucleus formation failure. This study provides new evidence that WEE2 mutations result in loss of function, which could result in fertilization failure.


2019 ◽  
Vol 32 (3) ◽  
pp. 295-300 ◽  
Author(s):  
Lina Zhu ◽  
Ruijuan Wu ◽  
Zhenlong Ye ◽  
Ruijie Gu ◽  
Yongxia Wang ◽  
...  

Abstract Background The mutations of thiamine pyrophosphokinase-1 (TPK1) gene have been frequently studied in some patients with thiamine metabolism dysfunction syndrome-5 (THMD5), while TPK1 mutations in Chinese patients have been investigated by only homozygous. A search of the literature on the mutations in the Chinese population currently published revealed that no reports of compound heterozygous mutations were reported. Here, we report a Chinese patient with compound heterozygous TPK1 mutations who underwent magnetic resonance imaging (MRI), whole exome sequencing (WES), molecular diagnosis, bioinformatics analysis, and three-dimensional (3D) protein structure analysis. Case presentation A Chinese boy was born after an uneventful pregnancy to non-consanguineous and healthy parents. On the sixth day after his birth, the lactate level of the patient was between 8.6 mmol/L and 14.59 mmol/L in plasma (the normal level is in the range of 0.5–2.2 mmol/L). Lactate was reduced to the normal level after rehydration, acid correction, expansion, and other treatments. After 4 months, the patient presented with an acute, 3-h-long, non-induced convulsions, and was admitted to our hospital for weakness, decreased oral intake, and lethargy. Results achieved by electroencephalography (EEG), cerebrospinal fluid, and other biochemical findings were normal. A visible hemorrhagic lesion was also observed in the brain. Seizures increased significantly during infection, which was accompanied by higher lactic acid levels. MRI of the brain showed an obvious signal shadow, in which bilateral frontal and temporal parietal subarachnoid cavities were widened, and more abnormal signals were observed; therefore, further consideration of hypoxic-ischemic encephalopathy and genetic metabolic disease was taken into account. Conclusions The results of WES revealed that the patient was associated with compound heterozygous mutations NM_022445.3:c.[263G>A]; [226A>G] of TPK1. His parents were non-consanguineous; while his father was found to be a heterozygous carrier with the mutation c.[263G>A], his mother was identified as a heterozygous carrier with the mutation c.[226A>G]. The results indicated that the patient had a compound heterozygous TPK1 mutation, and this is the first reported case in China.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5033-5033
Author(s):  
Rong-Fu Zhou ◽  
Qian Li ◽  
Min Zhou

Abstract Objective: To investigate the molecular pathogenesis of two coagulation factor XI (FXI) deficiency patients. Methods: The diagnosis was validated by coagulant assays: APTT and correct test, PT, INR and coagulation factors activities. Coagulation factor activity were tested with clotting assay. The patients' DNA were extracted and all exons and flanking sequences of FXI gene were amplified using PCR. After purified, the products were sent for sequencing directly, the mutations were detected by comparing with wild sequences and analyzed using some bioinformatics software. Results: The two patients were diagnosed as coagulation factor XI deficiency due to prolonged APTT and low activities of coagulation factor FXI. The results of APTT, FXI:C was 88.1s, 1.1% and 107.1s, 3.8% , respectively. Genetic analysis found that compound heterozygous mutations g.1251-1G > A and g.1271delT in the first patient and the sequencing results of TA plasmid clones showed that the two mutations were located on different single strands of chromosomes. Double heterozygous mutations g.1070A >G and g.1446C > G were detected in the second patient, resulting in Lys357Arg and Cys482Stop. Software analysis indicated the mutations probably brought amino acid sequence changed, protein features affected and splice site changed. Conclusion: Compound heterozygous mutations g.1251-1G > A, g.1271delT and g.1070A > G , g.1446C > G had been identified in two coagulation factor XI deficiency patients, which might be the cause of their prolonged APTT and low FXI:C. To the best of our knowledge, the four mutations are reported for the first time in the literature. Figure. Figure. Disclosures No relevant conflicts of interest to declare.


2015 ◽  
Vol 52 (5) ◽  
pp. e7-e8 ◽  
Author(s):  
Kazuyuki Nakamura ◽  
Takehiko Inui ◽  
Fuyuki Miya ◽  
Yonehiro Kanemura ◽  
Nobuhiko Okamoto ◽  
...  

2021 ◽  
Author(s):  
Yamato Ishida ◽  
Takuya Kobayashi ◽  
Shuhei Chiba ◽  
Yohei Katoh ◽  
Kazuhisa Nakayama

Abstract Primary cilia contain specific proteins to achieve their functions as cellular antennae. Ciliary protein trafficking is mediated by the intraflagellar transport (IFT) machinery containing the IFT-A and IFT-B complexes. Mutations in genes encoding the IFT-A subunits (IFT43, IFT121/WDR35, IFT122, IFT139/TTC21B, IFT140, and IFT144/WDR19) often result in skeletal ciliopathies, including cranioectodermal dysplasia (CED). We here characterized the molecular and cellular defects of CED caused by compound heterozygous mutations in IFT144 [the missense variant IFT144(L710S) and the nonsense variant IFT144(R1103*)]. These two variants were distinct with regard to their interactions with other IFT-A subunits and with the IFT-B complex. When exogenously expressed in IFT144-knockout (KO) cells, IFT144(L710S) as well as IFT144(WT) rescued both moderately compromised ciliogenesis and the abnormal localization of ciliary proteins. As the homozygous IFT144(L710S) mutation was found to cause autosomal recessive retinitis pigmentosa, IFT144(L710S) is likely to be hypomorphic at the cellular level. In striking contrast, the exogenous expression of IFT144(R1103*) in IFT144-KO cells exacerbated the ciliogenesis defects. The expression of IFT144(R1103*) together with IFT144(WT) restored the abnormal phenotypes of IFT144-KO cells. However, the coexpression of IFT144(R1103*) with the hypomorphic IFT144(L710S) variant in IFT144-KO cells, which mimics the genotype of compound heterozygous CED patients, resulted in severe ciliogenesis defects. Taken together, these observations demonstrate that compound heterozygous mutations in IFT144 cause severe ciliary defects via a complicated mechanism, where one allele can cause severe ciliary defects when combined with a hypomorphic allele.


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