An active controllable wide-angle and ultra-wideband terahertz absorber/reflector based on VO2 metamaterial.

The use of metamaterials in the design of optics is an important strategy for controlling light fields. Numerous terahertz metamaterial devices have been recently designed; however, their performance is relatively limited. Here, the thermally induced phase change characteristics of vanadium dioxide (VO2) were harnessed to design a perfect wide-angle and ultra-wideband switchable terahertz absorber/reflector with a simple structure and three layers from top to bottom (VO2, SiO2, and Au). The absorption mechanism based on the impedance matching theory and electric field distribution was investigated, and the influence of structural parameters on the absorption rate and performance of the absorber in a wide wave vector range were analyzed. The study findings showed that the device perfectly absorbed a bandwidth of over 6.0 THz (absorption >90%). The absorption (reflection) was modulated from 0.01 to 0.999 with the change of the background temperature. More importantly, the device could switch between complete ultra-wideband reflection and perfect absorption over a wide angle range. This study provides important insights into the design of terahertz functional devices.

Stretchable, Programmable and Magnet-Insensitive Protonic Display Based on Integrated Ionic Circuit.

As a new approach to "More than Moore", integrated ionic circuits serve as a possible alternative to traditional electronic circuits, yet the integrated ionic circuit composed of functional ionic elements and ionic connections is still challenging. Herein, a stretchable and transparent ionic display module of the integrated ionic circuit has been successfully prepared and demonstrated by pixelating a proton-responsive hydrogel. It is programmed to excite the hydrogel color change by a Faraday process occurring at the electrode at the specific pixel points, which enables the display of digital information and even color information. Importantly, the display module exhibits stable performance under strong magnetic field conditions (1.7 T). The transparent and stretchable nature of such ionic modules also allows them to be utilized in a broad range of scenarios, which paves the way for integrated ionic circuits.

X-rays irradiation maintains redox homeostasis and regulates energy metabolism of fresh figs (Ficus carica L. Siluhongyu).

In this study, figs were irradiated with X-rays doses of 1.0, 3.0, and 5.0 kGy and stored at 4 °C for 20 d to evaluate effects of X-ray on redox homeostasis and energy metabolism in figs. Non-irradiated figs were recorded as control group. Results indicated that 3.0 kGy X-rays delayed fig color discoloration by inhibiting the ΔE* values. The electrolyte leakage, MDA and O2-· levels of figs were significantly alleviated. Energy metabolism assay revealed that 3.0 kGy X-rays could significantly maintain higher activities of H+-ATPase, Ca2+-ATPase, SDH, CCO, G6PDH and 6PGDH of figs. 3.0 kGy X-rays also retained mitochondria membrane integrity of figs. Furthermore, 3.0 kGy X-rays resulted in 26.09 % higher NADK activity and 16.30 % lower NADH content than the control. The study proves that X-ray irradiation can be used as figs preservation means to maintain redox homeostasis and regulate energy metabolism, thus lengthening the shelf life of figs.

Mosaic variegated aneuploidy syndrome with tetraploid, and predisposition to male infertility triggered by mutant CEP192.

In this study, we report on mosaic variegated aneuploidy (MVA) syndrome with tetraploidy and predisposition to infertility in a family. Sequencing analysis identified that the CEP192 biallelic variants (c.1912C>T, p.His638Tyr and c.5750A>G, p.Asn1917Ser) segregated with microcephaly, short stature, limb-extremity dysplasia, and reduced testicular size, while CEP192 monoallelic variants segregated with infertility and/or reduced testicular size in the family. In 1,264 unrelated patients, variant screening for CEP192 identified a same variant (c.5750A>G, p.Asn1917Ser) and other variants significantly associated with infertility. Two lines of Cep192 mice model that are equivalent to human variants were generated. Embryos with Cep192 biallelic variants arrested at E7 because of cell apoptosis mediated by MVA/tetraploidy cell acumination. Mice with heterozygous variants replicated the predisposition to male infertility. Mouse primary embryonic fibroblasts with Cep192 biallelic variants cultured in vitro showed abnormal morphology, mitotic arresting, and disruption of spindle formation. In patient epithelial cells with biallelic variants cultured in vitro, the number of cells arrested during the prophase increased because of the failure of spindle formation. Accordingly, we present mutant CEP192, which is a link for the MVA syndrome with tetraploidy and the predisposition to male infertility.

Terahertz absorber based on vanadium dioxide with high sensitivity and switching capability between ultra-wideband and ultra-narrowband.

The terahertz perfect absorber can be applied in the control, sensing and modulation of optical fields in micro- and nanostructures. However, they are only single function, complex device structure and low sensing sensitivity. Based on this, by introducing the bound state in the continuum (BIC) with infinite quality factor and field enhancement effect, and taking advantage of the phase transition characteristics of vanadium dioxide (VO2), we designed a terahertz perfect absorber device which can actively switch between ultra-wideband and ultra-narrowband. The absorption mechanism is explained by multipole analysis theory, impedance matching theory and electromagnetic field distribution. The broadband absorption is mainly due to the electric dipole resonance on metallic VO2 materials, and the absorption is more than 99% across 3.64-6.96 THz, and it has excellent characteristics such as robustness. Ultra-narrowband perfect absorption has a quality factor greater than 2200 due mainly to the implementation of symmetrically protected BIC with a sensing sensitivity of 2.575 THz per RIU. Therefore, this research could be widely used in the fields of integrated optical circuits, optoelectronic sensing and perceptual modulation of energy, as well as providing additional design ideas for the design of terahertz multifunctional devices.

Chinese patients with 3M syndrome: clinical manifestations and two novel pathogenic variants.

Background: 3M syndrome is a rare autosomal recessive disease, characterized by intrauterine and postnatal growth retardation, facial dysmorphism, large head circumference, and skeletal changes, has rarely been reported in the Chinese population. Methods: We describe the clinical manifestations and gene variants in four sporadic cases of 3M syndrome in Chinese individuals from different families. Results: All cases had significant growth retardation, relative macrocephaly, and typical facial features. Exome sequencing revealed that two patients with 3M syndrome had homozygous variants of the CUL7 gene: one novel pathogenic variant and one previously reported pathogenic variant; the other two patients were heterozygous for variants in OBSL1, one of which had not been reported previously. Clinical evaluation indicated that these Chinese patients with 3M syndrome shared similar recognizable features with those reported in patients of other ethnic backgrounds, but not all patients with 3M syndrome in this study had normal development milestones. Two patients underwent recombinant human growth hormone (rhGH) therapy and showed accelerated growth in the first 2 years; however, the growth rate slowed in the third year in one case. There were no obvious adverse reactions during rhGH treatment. Conclusion: We report one novel CUL7 and one novel OBSL1 mutation in patients with 3M syndrome. Children with short stature, specific facial features, and physical symptoms should be referred for genetic testing to obtain precise diagnosis and appropriate treatment. The effects of rhGH treatment on adult height requires long-term observation and study in a large sample.

Antifreezing, Adhesive, and Ultra-Stretchable Ionogel for AI-Enabled Motion Tracking and Recognition in Winter Sports.

Motion tracking and recognition are gaining increasing attention in athletes' training for winter sports due to their importance in posture correction and injury prevention. Electronic skin serves as a better candidate compared to vision-based methods. However, the challenges of its application include sensing materials with good stretchability, softness, anti-freeze, non-volatility, and adhesion, and data processing techniques of high intelligence and efficiency. Here, we propose an antifreezing, adhesive, and ultra-stretchable organic ionogel (OIG). Maximum elongation of over 6500% has been obtained for the OIG of the double network, and the mechanical stretchability is retained at temperatures ranging from -50 to 50 °C. Importantly, the multi-sensor system could realize motion "recognition" rather than "perception" with the help of a convolutional neural network.

Novel Loss of Function (G15D) Mutation on RAC2 in a Family with Combined Immunodeficiency and Increased Levels of Immunoglobulin G, A, and E.

Ras-related C3 botulinum toxin substrate 2 (RAC2) is a small guanine nucleotide binding molecule that is exclusively expressed in hematopoietic cell lineages as a switcher. Based on in vivo and/or in vitro model experiments, RAC2 plays important roles in different cells through proliferation, secretion, and phagocytosis. It also performs a suppressing function in immunoglobulin (Ig) switching in Rac2-/- animals or cells. Several RAC2 natural mutations have been described in patients with primary immunodeficiency. RAC2 mutations can be classified into loss-of-function inactivating (LoF-I) and gain-of-function activating mutations according to their functional effects. Only two LoF-I mutations on RAC2 have been reported, including a dominant D57N mutation in several cases that exhibit granulocyte function defects and a recessive D56X mutation in cases with common variable immunodeficiency. Regardless of the type of mutation, most of the reported RAC2 mutant cases have shown reduced IgG, IgA, and IgM levels. Herein, we report on a family with three members that suffer from persistent HPV infection, recurrent respiratory infections, bronchiectasis, and autoimmune disease. The immunologic profile suggests that the family was affected by combined immunodeficiency (CID) with increased serum levels of IgG, IgA, and IgE. Exome sequencing identified a de novo RAC2 mutation (c.44G > A/p.G15D) that was co-segregated with the disease in the family. Gene functional experiments identified that such mutation results in reduced guanosine triphosphate binding activity and RAC2 protein expression. In patients' lymphocytes, impaired aggregation and proliferation effects, decreased mitochondrial membrane potential, and increased levels of cell apoptosis were observed, although no functional abnormalities were detected in neutrophils. To our knowledge, this study was the first to identify a LoF-I mutation of RAC2 affecting lymphocyte function that consequently led to CID and increased levels of serum IgG, IgE, and IgA. This study presents a novel subtype of RAC2-related immune disorder.

Mutant B3GALT6 in a Multiplex Family: A Dominant Variant Co-Segregated With Moderate Malformations.

B3GALT6 is a well-documented disease-related gene. Several B3GALT6-recessive variants have been reported to cause Ehlers-Danlos syndrome (EDS). To the best of our knowledge, no dominant B3GALT6 variant that causes human disease has been reported. In 2012, we reported on a three-generation, autosomal-dominant family with multiple members who suffered from radioulnar joint rotation limitation, scoliosis, thick vermilion of both lips, and others, but the genetic cause was unknown. Here, exome sequencing of the family identified mutant B3GALT6 as the cause of the multiplex affected family. We observed that, in the compound heterozygous pattern (i.e., c.883C>T:p.R295C and c.510_517del:p.L170fs*268), mutant B3GALT6 led to severe consequences, and in the dominant pattern, an elongated B3GALT6 variant co-segregated with moderate phenotypes. The functional experiments were performed in vitro. The R295C variant led to subcellular mislocalization, whereas the L170fs*268 showed normal subcellular localization, but it led to an elongated protein. Given that most of the catalytic galactosyltransferase domain was disrupted for the L170fs*268 (it is unlikely that such a protein has activity), we propose that the L170fs*268 occupies the normal B3GALT6 protein position in the Golgi and exerts a dominant-negative effect.

Case Report: MYO5B Homozygous Variant c.2090+3A>T Causes Intron Retention Related to Chronic Cholestasis and Diarrhea.

Background: Biallelically mutated MYO5B is associated with microvillus inclusion disease (MVID, MIM: 251850), cholestasis, or both. This study aims at validating the splicing alteration and clinical features of an intron variant for diagnosis. Case Presentation: A homozygous variant of MYO5B, NM_001080467.2:c.2090+3A > T (NP_001073936.1:p.?) in intron 17, was identified in a patient suffering from chronic cholestasis and diarrhea. Functional validation showed that this variant caused 185 bp of intron retention in its mRNA and was predicted to present a premature translation termination site for myoVb (p.Arg697fs*47) in the head motor domain. In addition, bowel biopsy revealed decreased microvilli and local lesions of microvillus inclusion in the duodena of the patient. The patient was presented with neonatal cholestasis leading to cirrhosis, intractable diarrhea, cholelithiasis, hepatic cyst, corneal opacity, and failure to thrive. Conclusion: Our study demonstrated an intronic homozygous variant of MYO5B that affected an intron, subsequently altering splicing and leading to combined cholestasis and MVID. Our results further supported the underlying genotype-phenotype correlations and extended clinical practices toward its diagnosis and management.

MECOM-related disorder: Radioulnar synostosis without hematological aberration due to unique variants.

PURPOSE: The etiology for a considerable proportion of patients with congenital radioulnar synostosis (RUS) remains unclear. This study aimed to investigate the genetic cause of RUS without a known cause. METHODS: Patients with RUS were investigated. Exome sequencing and/or Sanger sequencing was performed. Bioinformatics analysis was also performed. Pathogenicity was evaluated for variants of interest. RESULTS: We identified unique missense variants in MECOM (encodes EVI1) associated with RUS in 8 families. Of them, 6 families had variants in residue R781, including 3 families with R781C (c.2341C>T), 2 families with R781H (c.2342G>A), and 1 family with R781L (c.2342G>T). Another 2 variants included I783T (c.2348T>C) in 1 family and Q777E (c.2329C>G) in 1 family. All these variants were clustered within the ninth zinc finger motif of EVI1. Phenotype evaluation identified that most of these patients with RUS harboring mutant MECOM had finger malformations, but none of them had identifiable hematological abnormalities. Functional experiments showed that MECOM R781C led to alterations in TGF-ß-mediated transcriptional responses. CONCLUSION: This study examined MECOM variants by focusing on RUS instead of hematological abnormalities. The R781 residue in EVI1 is a hotspot for human RUS variants. Mutant MECOM is the second most common cause for familial RUS.

Case series of congenital pseudarthrosis of the tibia unfulfilling neurofibromatosis type 1 diagnosis: 21% with somatic NF1 haploinsufficiency in the periosteum.

Up to 84% of patients with congenital pseudarthrosis of the tibia (CPT) present with neurofibromatosis type 1 (NF1) (NF1-CPT). However, the etiology of CPT not fulfilling the NIH diagnostic criteria for NF1 (non-NF1-CPT) is not well understood. Here, we collected the periosteum tissue from the pseudarthrosis (PA) site of 43 non-NF1-CPT patients and six patients with NF1-CPT, together with the blood or oral specimen of trios (probands and unaffected parents). Whole-exome plus copy number variation sequencing, multiplex ligation-dependent probe amplification (MLPA), ultra-high amplicon sequencing, and Sanger sequencing were employed to identify pathogenic variants. The result showed that nine tissues of 43 non-NF1-CPT patients (21%) had somatic mono-allelic NF1 inactivation, and five of six NF1-CPT patients (83.3%) had bi-allelic NF1 inactivation in tissues. However, previous literature involving genetic testing did not reveal somatic mosaicism in non-NF1-CPT patients so far. In NF1-CPT patients, when the results from earlier reports and the present study were combined, 66.7% of them showed somatic NF1 inactivation in PA tissues other than germline inactivation. Furthermore, no diagnostic variants from other known genes (GNAS, AKT1, PDGFRB, and NOTCH3) related to skeletal dysplasia were identified in the nine NF1 positive non-NF1-CPT patients and six NF1-CPT patients. In conclusion, we detected evident somatic mono-allelic NF1 inactivation in the non-NF1-CPT. Thus, for pediatric patients without NF1 diagnosis, somatic mutations in NF1 are important.

A genotype and phenotype analysis of SMAD6 mutant patients with radioulnar synostosis.

BACKGROUND: SMAD6 variants have been reported in patients with radioulnar synostosis (RUS). This study aimed to investigate the genotypes and phenotypes for a large cohort of patients with RUS having mutant SMAD6. METHODS: Genomic DNA samples were isolated from 251 RUS sporadic patients (with their parents) and 27 RUS pedigrees. Sanger sequencing was performed for the SMAD6 coding regions. For positive probands, co-segregation and parental-origin analysis of SMAD6 variants and phenotypic re-evaluation were performed for their family members. RESULTS: We identified 50 RUS probands with SMAD6 variants (13 co-segregated with RUS in pedigrees and 37 in RUS-sporadic patients). Based on the new and previous data, we identified SMAD6 mutated in 16/38 RUS pedigrees and 61/393 RUS sporadic patients, respectively. Overall, 93 SMAD6 mutant patients with RUS were identified, among which 29 patients had unilateral RUS, where the left side was more involved than the right side (left:right = 20:9). Female protective effects and non-full penetrance were observed, in which only 6.90% mothers (vs. ~50% fathers) of SMAD6 mutant RUS probands had RUS. Pleiotropy was observed as a re-evaluation of SMAD6 mutant families identified: (a) three families had axial skeletal malformations; (b) two families had polydactyly; and (c) eight families had other known malformations. CONCLUSION: SMAD6 was mutated in 42.11% RUS pedigrees and 15.52% RUS sporadic patients. The RUS patients with SMAD6 variants exhibit both non-full-penetrance, variable expressivity, pleiotropy, female protective effects, and the left side is more susceptible than the right side.

Expanding the genotypes and phenotypes for 19 rare diseases by exome sequencing performed in pediatric intensive care unit.

Phenotypes of some rare genetic diseases are atypical and it is a challenge for pediatric intensive care units (PICUs) to diagnose and manage such patients in an emergency. In this study, we investigated 58 PICU patients (39 deceased and 19 surviving) in critical ill status or died shortly without a clear etiology. Whole exome sequencing was performed of 103 DNA samples from their families. Disease-causing single-nucleotide variants (SNVs) and copy number variants (CNVs) were identified to do genotype-phenotypes analysis. In total, 27 (46.6%) patients received a genetic diagnosis. We identified 34 pathogenic or likely pathogenic SNVs from 26 genes, which are related to at least 19 rare diseases. Each rare disease involved an isolated patient except two patients caused by the same gene ACAT1. The genotypic spectrum was expanded by 23 novel SNVs from gene MARS1, PRRT2, TBCK, TOR1A, ECE1, ARX, ZEB2, ACAT1, CPS1, VWF, NBAS, COG4, and INVS. We also identified two novel pathogenic CNVs. Phenotypes associated with respiratory, multiple congenital anomalies, neuromuscular, or metabolic disorders were the most common. Twenty patients (74.1%) accompanied severe infection, 19 patients (70.1%) died. In summary, our findings expanded the genotypes and phenotypes of 19 rare diseases from PICU with complex characteristics.

Further phenotypic features and two novel POC1A variants in a patient with SOFT syndrome: A case report.

Short stature, onychodysplasia, facial dysmorphism and hypotrichosis (SOFT) syndrome is a rare autosomal recessive disease caused by POC1 centriolar protein A (POC1A) pathogenic variants. However, knowledge of genotypic and phenotypic features of SOFT syndrome remain limited as few families have been examined; therefore, the clinical identification of SOFT syndrome remains a challenge. The aim of the present case report was to investigate the genetic cause of this syndrome in a patient with a short stature, unusual facial appearance, skeletal dysplasia and sparse body hair. Giemsa banding and exome sequencing were performed to investigate the genetic background of the family. Spiral computed tomography and magnetic resonance imaging were used for investigating further phenotypic features of the patient. Exome sequencing identified that POC1A had two compound heterozygous variants, namely c.850_851insG and c.593_605delGTGGGACGTGCAT, which, to the best of our knowledge, have not been reported elsewhere. Novel phenotypes were also identified as follows: i) Metaphyseal dysplasia was alleviated (and/or even disappeared) with age; ii) the density of the femoral neck was uneven and the hyperintensity signal of the metaphysis was stripe­like. Thus, the present case report expands the knowledge regarding phenotypic and genotypic features of SOFT syndrome.

Disorder of Sexual Development Males With XYY in Blood Have Exactly X/XY/XYY Mosaicism in Gonad Tissues.

Y chromosome represents masculinization. The extra Y chromosome of XYY patients usually leads to over-masculinization phenotypes. The occurrence of several DSD cases with XYY in blood is controversial. Is XYY associated with disorder of sex development (DSD)? What is the mechanism behind DSD in males with XYY in blood? To this end, this study retrospectively analyzed blood-karyotype data of 4,437 DSD male children and karyotypes data of 6,259 newborn males as the control. Exome sequencing (ES) was performed to test whether the patients with DSD and with XYY in blood had other variants on known DSD-genes. Testicular biopsy was performed. Fluorescence in situ hybridization (FISH) was used to test whether a sex chromosome mosaicism was present in the oral epithelial cells or gonad tissue of patients with DSD and with XYY in blood. Among 4,437 DSD males who received cytogenetic evaluation, 14 patients with 47,XYY were identified. By contrast, five individuals among the 6,259 controls had 47,XYY. XYY in blood is more frequent among males with DSD than in other males (p = 0.004). The XYY karyotypes were confirmed again by GTG-banding in blood samples and by FISH performed on oral epithelial cells. ES on seven XYY DSD patients was successfully performed, but results did not identify any pathogenic variant on 55 known DSD genes. Gonad biopsy (n = 3) revealed testicular dysplasia and true hermaphroditism. FISH of gonad tissues (n = 3) showed that all of the samples had mosaic for X/XY/XYY. This study is the first to investigate the relationship between XYY in blood and DSD. The knowledge that XYY is in the blood and in oral cells have X/XY/XYY mosaicism in gonadal tissue is new for both researchers and clinicians who seek to understand the genetic basis of DSD males.

Genetic and Clinical Analyses of 13 Chinese Families With Cystine Urolithiasis and Identification of 15 Novel Pathogenic Variants in SLC3A1 and SLC7A9.

BACKGROUND: Cystinuria is a rare genetic disorder characterized by defective renal reabsorption of cystine, ornithine, arginine, and lysine. The increased urinary excretion of cystine results in the development of cystine urolithiasis (CU). The mutated SLC3A1 and SLC7A9 genes are the cause of CU, a global disorder. Its frequency and mutation spectrum vary between different populations. In Asia, the data for CU are limited. METHOD: Urinary stones were collected from patients of a single center over a five-year period and analyzed via Fourier transform infrared spectroscopy. Genomic DNA was isolated from 13 patients with CU and their parents and from 26 controls affected by calcium oxalate dihydrate stones. The coding regions and the exon-intron boundaries of SLC3A1 and SLC7A9 were subjected to PCR amplification and then sequenced via traditional Sanger sequencing. Genetic variants were functionally annotated using the InterVar, ClinVar, gnom AD, and HGMD databases. RESULTS: From the 232 samples of urinary stones, we identified 13 patients with CU (10 males and 3 females). The onset age was from 7 months to 9 years. The CU stones varied from 0.26 cm3 to 18.67 cm3. Sanger sequencing detected a total of 14 SLC3A1 (nine were novel) and 10 SLC7A9 (six were novel) rare variants from the 13 CU families. All variants, including 15 novel variants, were pathogenic, disease-causing, or damaging. CONCLUSION: All 13 pediatric CU families harbored SLC3A1 or/and SLC7A9 rare variants. A total of 15 novel pathogenic variants in SLC3A1 and SLC7A9 were identified. This study expanded the known mutational spectrum of CU in the Chinese population.

Case report: two novel VPS13B mutations in a Chinese family with Cohen syndrome and hyperlinear palms.

BACKGROUND: Cohen syndrome (CS) is an uncommon developmental disease with evident clinical heterogeneity. VPS13B is the only gene responsible for CS. Only few sporadic cases of CS have been reported in China. CASE PRESENTATION: A Chinese family with two offspring-patients affected by developmental delay and intellectual disability was investigated in this study. Exome sequencing was performed, and compound heterozygous mutations in VPS13B were segregated for family members with autosomal recessive disorder. Splicing mutation c.3666 + 1G > T (exon 24) and nonsense mutation c. 9844 A > T:p.K3282X (exon 54) were novel. We revisited the family and learned that both patients are affected by microcephaly, developmental delay, neutropenia, and myopia and have a friendly disposition, all of which are consistent with CS phenotypes. We also found that both patients have hyperlinear palms, which their parents do not have. VPS13B mutations reported among the Chinese population were reviewed accordingly. CONCLUSIONS: This study presents two novel VPS13B mutations in CS. The identification of hyperlinear palms in a family affected by CS expands the phenotype spectrum of CS.

Identification and characterization of NF1 and non-NF1 congenital pseudarthrosis of the tibia based on germline NF1 variants: genetic and clinical analysis of 75 patients.

BACKGROUND: Congenital pseudarthrosis of the tibia (CPT) is a rare disease. Some patients present neurofibromatosis type 1 (NF1), while some others do not manifest NF1 (non-NF1). The etiology of CPT, particularly non-NF1 CPT, is not well understood. Here we screened germline variants of 75 CPT cases, including 55 NF1 and 20 non-NF1. Clinical data were classified and analyzed based on NF1 gene variations to investigate the genotype-phenotype relations of the two types of patients. RESULTS: Using whole-exome sequencing and Multiplex Ligation-Dependent Probe Amplification, 44 out of 55 NF1 CPT patients (80.0%) were identified as carrying pathogenic variants of the NF1 gene. Twenty-five variants were novel; 53.5% of variants were de novo, and a higher proportion of their carriers presented bone fractures compared to inherited variant carriers. No NF1 pathogenic variants were found in all 20 non-NF1 patients. Clinical features comparing NF1 CPT to non-NF1 CPT did not show significant differences in bowing or fracture onset, lateralization, tissue pathogenical results, abnormality of the proximal tibial epiphysis, and follow-up tibial union after surgery. A considerably higher proportion of non-NF1 patients have cystic lesion (Crawford type III) and used braces after surgery. CONCLUSIONS: We analyzed a large cohort of non-NF1 and NF1 CPT patients and provided a new perspective for genotype-phenotype features related to germline NF1 variants. Non-NF1 CPT in general had similar clinical features of the tibia as NF1 CPT. Germline NF1 pathogenic variants could differentiate NF1 from non-NF1 CPT but could not explain the CPT heterogeneity of NF1 patients. Our results suggested that non-NF1 CPT was probably not caused by germline NF1 pathogenic variants. In addition to NF1, other genetic variants could also contribute to CPT pathogenesis. Our findings would facilitate the interpretation of NF1 pathogenic variants in CPT genetic counseling.