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Nonsyndromic hearing loss (NSHL), a common sensory disorder, is characterized by high clinical and genetic heterogeneity (i.e., approximately 115 genes and 170 loci so far identified). Nevertheless, almost half of patients submitted for genetic testing fail to receive a conclusive molecular diagnosis. We used next‐generation sequencing to identify causal variants in PLS1 (c.805G>A, p.[E269K]; c.713G>T, p.[L238R], and c.383T>C, p.[F128S]) in three unrelated families of European ancestry with autosomal dominant NSHL. PLS1 encodes Plastin 1 (also called fimbrin), one of the most abundant actin‐bundling proteins of the stereocilia. In silico protein modeling suggests that all variants destabilize the structure of the actin‐binding domain 1, likely reducing the protein's ability to bind F actin. The role of PLS1 gene in hearing function is further supported by the recent demonstration that Pls1?/? mice show a hearing loss phenotype similar to that of our patients. In summary, we report PLS1 as a novel gene for autosomal dominant NSHL, suggesting that this gene is required for normal hearing in humans and mice.  相似文献   
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The ACTN1 gene has been implicated in inherited macrothrombocytopenia. To decipher the spectrum of variants and phenotype of ACTN1‐related thrombocytopenia, we sequenced the ACTN1 gene in 272 cases of unexplained chronic or familial thrombocytopenia. We identified 15 rare, monoallelic, nonsynonymous and likely pathogenic ACTN1 variants in 20 index cases from 20 unrelated families. Thirty‐one family members exhibited thrombocytopenia. Targeted sequencing was carried out on 12 affected relatives, which confirmed presence of the variant. Twenty‐eight of 32 cases with monoallelic ACTN1 variants had mild to no bleeding complications. Eleven cases harbored 11 different unreported ACTN1 variants that were monoallelic and likely pathogenic. Nine variants were located in the α‐actinin‐1 (ACTN1) rod domain and were predicted to hinder dimer formation. These variants displayed a smaller increase in platelet size compared with variants located outside the rod domain. In vitro expression of the new ACTN1 variants induced actin network disorganization and led to increased thickness of actin fibers. These findings expand the repertoire of ACTN1 variants associated with thrombocytopenia and highlight the high frequency of ACTN1‐related thrombocytopenia cases. The rod domain, like other ACTN1 functional domains, may be mutated resulting in actin disorganization in vitro and thrombocytopenia with normal platelet size in most cases.  相似文献   
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High hyperdiploidy (HD) is the most common cytogenetic subtype of childhood acute lymphoblastic leukemia (ALL), and a higher incidence of HD has been reported in ALL patients with congenital cancer syndromes. We assessed the frequency of predisposing germline mutations in 57 HD‐ALL patients from the California Childhood Leukemia Study via targeted sequencing of cancer‐relevant genes. Three out of 57 patients (5.3%) harbored confirmed germline mutations that were likely causal, in NBN, ETV6, and FLT3, with an additional six patients (10.5%) harboring putative predisposing mutations that were rare in unselected individuals (<0.01% allele frequency in the Exome Aggregation Consortium, ExAC) and predicted functional (scaled CADD score ≥ 20) in known or potential ALL predisposition genes (SH2B3, CREBBP, PMS2, MLL, ABL1, and MYH9). Three additional patients carried rare and predicted damaging germline mutations in GAB2, a known activator of the ERK/MAPK and PI3K/AKT pathways and binding partner of PTPN11‐encoded SHP2. The frequency of rare and predicted functional germline GAB2 mutations was significantly higher in our patients (2.6%) than in ExAC (0.28%, P = 4.4 × 10?3), an observation that was replicated in ALL patients from the TARGET project (P = .034). We cloned patient GAB2 mutations and expressed mutant proteins in HEK293 cells and found that frameshift mutation P621fs led to reduced SHP2 binding and ERK1/2 phosphorylation but significantly increased AKT phosphorylation, suggesting possible RAS‐independent leukemogenic effects. Our results support a significant contribution of rare, high penetrance germline mutations to HD‐ALL etiology, and pinpoint GAB2 as a putative novel ALL predisposition gene.  相似文献   
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The career success of preschool teachers has been discussed to be important because it can be a precondition for the ability to provide a high-quality preschool education. Consequently, the identification of factors that can help explain individual differences in career success is a crucial research issue. Previous research covering various occupations indicates that the Big Five, internal locus of control (LOC), and occupational self-efficacy are good predictors of objective and subjective career success. However, there is a research gap on this topic in preschool teachers. This study examined whether the Big Five, LOC, and occupational self-efficacy could predict the career success of 560 preschool teachers in Germany. After controlling for other predictors, internal LOC corresponded with higher objective career success, but neuroticism and conscientiousness corresponded with lower subjective career success. Occupational self-efficacy corresponded with higher subjective career success. The findings are discussed with respect to practical conclusions.  相似文献   
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Nowadays aesthetic standards reflect a generalisation of western ones. We propose to outline an aesthetic concept about Ivorian face. A selected jury will have to judge fifty-three Ivorian faces, through photographs and also, we'll make the cephalometric analysis of flabby and osseous tissues. We expect then, to provide orthodontists with basic references whenever they have to establish treatment objectives, for Negro-African, (particularly Ivorian), patients with facial disharmony evaluated according to western norms.  相似文献   
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