WNT10A, dermatology and dentistry

The relevance of taurodontism in forensic dental age estimation

Taurodontism is a dental morphological anomaly characterized by enlarged pulp cavities repositioned towards the apical region of the tooth, coupled with shortened root structures. Molars are commonly affected by this alteration. Certain populations exhibit up to 48% prevalences for this dental alteration, underscoring its significance in dental age estimation (DAE). In the field of DAE, an individual's chronological age is inferred from specific dental features, frequently employed within the forensic context. The effect of taurodontism on the features of DAE is an unanswered issue. The influence of taurodontism on eruption, mineralization, radiographic visibility of root canals, and radiographic visibility of the periodontal ligament space in mandibular third molars- some of the established criteria for DAE as examples-is currently not systematically examined. Some common staging scales for the dental features of DAE cannot technically be applied to taurodontic teeth. Additionally, given the association of taurodontism with syndromes affecting tooth development, caution is warranted in age assessment procedures. Notably, taurodontic teeth may serve as indicators of syndromes influencing skeletal development, further emphasizing the relevance of taurodontism in forensic age assessment. Presumably taurodontic teeth were included in reference data to some extent due to their partially high prevalence in the past, whereby the influence of taurodontism has been statistically absorbed within the overall spread of the features. Future studies should compare the temporal course of these tooth characteristics in affected and unaffected teeth. Subsequent initiatives should focus on raising awareness among forensic dentists regarding taurodontism, necessitating in-depth exploration of the subject.

Genetic Variants in KCTD1 Are Associated with Isolated Dental Anomalies

KCTD1 plays crucial roles in regulating both the SHH and WNT/β-catenin signaling pathways, which are essential for tooth development. The objective of this study was to investigate if genetic variants in KCTD1 might also be associated with isolated dental anomalies. We clinically and radiographically investigated 362 patients affected with isolated dental anomalies. Whole exome sequencing identified two unrelated families with rare (p.Arg241Gln) or novel (p.Pro243Ser) variants in KCTD1. The variants segregated with the dental anomalies in all nine patients from the two families. Clinical findings of the patients included taurodontism, unseparated roots, long roots, tooth agenesis, a supernumerary tooth, torus palatinus, and torus mandibularis. The role of Kctd1 in root development is supported by our immunohistochemical study showing high expression of Kctd1 in Hertwig epithelial root sheath. The KCTD1 variants in our patients are the first variants found to be located in the C-terminal domain, which might disrupt protein-protein interactions and/or SUMOylation and subsequently result in aberrant WNT-SHH-BMP signaling and isolated dental anomalies. Functional studies on the p.Arg241Gln variant are consistent with an impact on β-catenin levels and canonical WNT signaling. This is the first report of the association of KCTD1 variants and isolated dental anomalies.

Bimaxillary fixed implant-supported zirconium oxide prosthesis therapy of an adolescent patient with non-syndromic oligodontia and two WNT10 variants: a case report

Introduction and importance

Oligodontia is a rare genetic condition characterized by more than six congenitally missing teeth, either as an isolated non-syndromic condition or in association with other genetic syndromes. The impact of WNT10A variants on dental development increases with the presence of the c.321C>A variant and the number of missing teeth.

Case presentation

A 21-year-old man with non-syndromic oligodontia was diagnosed at 15 years of age with misaligned teeth, speech problems, and the absence of 24 permanent teeth. Interdisciplinary collaboration between specialists was initiated to enable comprehensive treatment. DNA analysis confirmed that the patient was a carrier of the known pathogenic WNT10A variant c321C>A and WNT10A variant c.113G>T of unknown clinical significance.

Clinical discussion

Dental implants are a common treatment; however, bone development challenges in adolescent patients with non-syndromic oligodontia necessitate careful planning to ensure implant success. Many WNT variants play crucial roles in tooth development and are directly involved in non-syndromic oligodontia, especially the WNT10 variant c.321C>A.

Conclusion

A full-arch implant-supported monolithic zirconia screw-retained fixed prosthesis is a viable treatment option for young adults with non-syndromic oligodontia. Further studies are needed to clarify the possible amplifying effect of the WNT10A variants c321C>A and c.113G>T on the pathogenic phenotype of non-syndromic oligodontia.

Hair Evaluation in Orthodontic Patients with Oligodontia

Oligodontia can be isolated or syndromic, associated with other ectodermal abnormalities. The aim of the study was to perform hair examination in orthodontic patients diagnosed with oligodontia with a low clinical expression of symptoms of ectodermal origin. All available orthodontic patients diagnosed with oligodontia in the permanent dentition were enrolled. Hair examination included clinical evaluation of the patients' hair, trichoscopy, trichogram and evaluation of the hair shafts under a polarized light microscope. In total, 25 patients, 18 males and 7 females, aged 6 to 24 years were evaluated for the presence of dental and hair abnormalities. The number of congenitally absent teeth ranged from 6 to 24 teeth and diastemas, microdontia, taurodontism and altered tooth shape were found in 23 patients. Hair disorders were found in 68% of the subjects. Hypotrichosis, the heterogeneity of shaft color and loss of pigment, androgenetic alopecia, telogen effluvium, trichoschisis, pili canaliculi, trichorrhexis nodosa and pseudomoniletrix were observed. Trichoscopy and trichogram are valid non-invasive diagnostic tests which could be used to differentiate between isolated and syndromic oligodontia in patients with a low clinical expression of ectodermal symptoms.

Acne-induced pathological scars: pathophysiology and current treatments

Acne is a common chronic inflammatory dermatosis that can lead to pathological scars (PSs, divided into hypertrophic scars and keloids). These kinds of abnormal scars seriously reduce the quality of life of patients. However, their mechanism is still unclear, resulting in difficult clinical prevention, unstable treatment effects and a high risk of recurrence. Available evidence supports inflammatory changes caused by infection as one of the keys to abnormal proliferation of skin fibroblasts. In acne-induced PSs, increasing knowledge of the immunopathology indicates that inflammatory cells directly secrete growth factors to activate fibroblasts and release pro-inflammatory factors to promote the formation of PSs. T helper cells contribute to PSs via the secretion of interleukin (IL)-4 and IL-13, the pro-inflammatory factors; while regulatory T cells have anti-inflammatory effects, secrete IL-10 and prostaglandin E2, and suppress fibrosis production. Several treatments are available, but there is a lack of combination regimens to target different aspects of acne-induced PSs. Overall, this review indicates that the joint involvement of inflammatory response and fibrosis plays a crucial role in acne-induced PSs, and also analyzes the interaction of current treatments for acne and PS.

Developmental and Acquired Abnormalities of the Teeth

This review aims to present a detailed analysis of the most common developmental and acquired dental abnormalities, including caries, resorptive lesions, and congenital anomalies of teeth number, size, form, and structure. This review highlights how diagnostic imaging can aid in the accurate identification and management of these conditions.

Novel frameshift variant of WNT10A in a Japanese patient with hypodontia

Congenital tooth agenesis is caused by the impairment of crucial genes related to tooth development, such as Wnt signaling pathway genes. Here, we investigated the genetic causes of sporadic congenital tooth agenesis. Exome sequencing, followed by Sanger sequencing, identified a novel single-nucleotide deletion in WNT10A (NC_000002.12(NM_025216.3):c.802del), which was not found in the healthy parents of the patient. Thus, we concluded that the variant was the genetic cause of the patient's agenesis.

Toothpastes for children and their detergent contents affect molecular mechanisms of odontogenesis in zebrafish embryos

We aimed to evaluate how different types of toothpaste (TP) for children affected molecular mechanisms of odontogenesis in zebrafish embryos. Commercially available TPs were selected according to their detergent contents as the cocamidopropyl betaine (CAPB) containing TP (TP1) and sodium lauryl sulfate (SLS) containing TP (TP2). TP3 contained no detergent. Effects of SLS, and CAPB alone were also examined. TP and detergent concentrations affecting development were determined as 750 mg/L and 4 mg/L, respectively. Embryos were exposed to TP1, TP2, TP3, SLS, CAPB, and embryo medium (control) for 72 h post fertilization. Acetylcholinesterase (AChE) activity and oxidant-antioxidant parameters were analyzed spectrophotometrically. Expressions of tooth development genes were evaluated by reverse transcription PCR (RT-PCR). Intraocular distance, lower jaw, and ceratohyal cartilage length were displayed using Alcian Blue staining. axin2 and wnt10a expressions increased in SLS and TP2 groups. igf2a and eve1 expressions decreased in all groups except TP3. nrOb1 expression decreased in TP1, SLS, and CAPB groups. Oxidant-antioxidant balance was disturbed in all groups except TP3, evidenced by increased lipid peroxidation, nitric oxide. SLS, and CAPB groups were more affected in terms of AChE, glutathione-S-transferase, and superoxide dismutase; perturbations were observed in cartilage structures. Altered expression of tooth development gene axin2 correlated with wnt10a, and with changes in cartilage structures in SLS and TP2 groups. TP3 group presented no disruptions in oxidant-antioxidant balance. Our study shows the availability of externally developing zebrafish embryos in examining the effects of TP' contents on embryogenesis.

Dominant frontonasal dysplasia with ectodermal defects results from increased activity of ALX4

Frontonasal dysplasia (FND) refers to a group of rare developmental disorders characterized by abnormal morphology of the craniofacial region. We studied a family manifesting with clinical features typical for FND2 including neurobehavioral abnormalities, hypotrichosis, hypodontia, and facial dysmorphism. Whole-exome sequencing analysis identified a novel heterozygous frameshift insertion in ALX4 (c.985_986insGTGC, p.Pro329Argfs*115), encoding aristaless homeobox 4. This and a previously reported dominant FND2-causing variant are predicted to result in the formation of a similar abnormally elongated protein tail domain. Using a reporter assay, we showed that the elongated ALX4 displays increased activity. ALX4 negatively regulates the Wnt/β-catenin pathway and accordingly, patient keratinocytes showed altered expression of genes associated with the WNT/β-catenin pathway, which in turn may underlie ectodermal manifestations in FND2. In conclusion, dominant FND2 with ectodermal dysplasia results from frameshift variants in ALX4 exerting a gain-of-function effect.

Physicochemical understanding of biomineralization by molecular vibrational spectroscopy: From mechanism to nature

The process and mechanism of biomineralization and relevant physicochemical properties of mineral crystals are remarkably sophisticated multidisciplinary fields that include biology, chemistry, physics, and materials science. The components of the organic matter, structural construction of minerals, and related mechanical interaction, etc., could help to reveal the unique nature of the special mineralization process. Herein, the paper provides an overview of the biomineralization process from the perspective of molecular vibrational spectroscopy, including the physicochemical properties of biomineralized tissues, from physiological to applied mineralization. These physicochemical characteristics closely to the hierarchical mineralization process include biological crystal defects, chemical bonding, atomic doping, structural changes, and content changes in organic matter, along with the interface between biocrystals and organic matter as well as the specific mechanical effects for hardness and toughness. Based on those observations, the special physiological properties of mineralization for enamel and bone, as well as the possible mechanism of pathological mineralization and calcification such as atherosclerosis, tumor micro mineralization, and urolithiasis are also reviewed and discussed. Indeed, the clearly defined physicochemical properties of mineral crystals could pave the way for studies on the mechanisms and applications.

Short anagen hair syndrome: association with mono- and biallelic variants in WNT10A and a genetic overlap with male pattern hair loss

BACKGROUND

Short anagen hair (SAH) is a rare paediatric hair disorder characterized by a short anagen phase, an inability to grow long scalp hair and a negative psychological impact. The genetic basis of SAH is currently unknown.

OBJECTIVES

To perform molecular genetic investigations in 48 individuals with a clinical phenotype suggestive of SAH to identify, if any, the genetic basis of this condition.

METHODS

Exome sequencing was performed in 27 patients diagnosed with SAH or with a complaint of short, nongrowing hair. The cohort was screened for variants with a minor allele frequency (MAF) < 5% in the general population and a Combined Annotation Dependent Depletion (CADD) score > 15, to identify genes whose variants were enriched in this cohort. Sanger sequencing was used for variant validation and screening of 21 additional individuals with the same clinical diagnosis and their relatives. Genetic association testing of SAH-related variants for male pattern hair loss (MPHL) was performed using UK Biobank data.

RESULTS

Analyses revealed that 20 individuals (42%) carried mono- or biallelic pathogenic variants in WNT10A. Rare WNT10A variants are associated with a phenotypic spectrum ranging from no clinical signs to severe ectodermal dysplasia. A significant association was found between WNT10A and SAH, and this was mostly observed in individuals with light-coloured hair and regression of the frontoparietal hairline. Notably, the most frequent variant in the cohort [c.682T>A;p.(Phe228Ile)] was in linkage disequilibrium with four common WNT10A variants, all of which have a known association with MPHL. Using UK Biobank data, our analyses showed that c.682T>A;p.(Phe228Ile) and one other variant identified in the SAH cohort are also associated with MPHL, and partially explain the known associations between WNT10A and MPHL.

CONCLUSIONS

Our results suggest that WNT10A is associated with SAH and that SAH has a genetic overlap with the common phenotype MPHL. The presumed shared biologic effect of WNT10A variants in SAH and MPHL is a shortening of the anagen phase. Other factors, such as modifier genes and sex, may also play a role in the clinical manifestation of hair phenotypes associated with the WNT10A locus.

Count Me in, Count Me out: Regulation of the Tooth Number via Three Directional Developmental Patterns

Tooth number anomalies, including hyperdontia and hypodontia, are common congenital dental problems in the dental clinic. The precise number of teeth in a dentition is essential for proper speech, mastication, and aesthetics. Teeth are ectodermal organs that develop from the interaction of a thickened epithelium (dental placode) with the neural-crest-derived ectomesenchyme. There is extensive histological, molecular, and genetic evidence regarding how the tooth number is regulated in this serial process, but there is currently no universal classification for tooth number abnormalities. In this review, we propose a novel regulatory network for the tooth number based on the inherent dentition formation process. This network includes three intuitive directions: the development of a single tooth, the formation of a single dentition with elongation of the continual lamina, and tooth replacement with the development of the successional lamina. This article summarizes recent reports on early tooth development and provides an analytical framework to classify future relevant experiments.

Wnt10a downregulation contributes to MEHP-induced disruption of self-renewal and differentiation balance and proliferation inhibition in GC-1 cells: Insights from multiple transcriptomic profiling

Di (2-ethylhexyl) phthalate (DEHP), one of phthalic acid esters, has been widely used in daily products. Its main metabolite, mono (2-ethylhexyl) phthalate (MEHP) was reported to possess higher testicular toxicity than DEHP. To explore the precise mechanism in MEHP-induced testis damage, multiple transcriptomic sequencing was employed in spermatogonia cell line GC-1 cells treated with MEHP (0, 100, and 200 μM) for 24 h. Integrative omics analysis and empirical validation revealed that Wnt signaling pathway was downregulated and wnt10a, one of hub genes, may be the key player in this process. Similar results were observed in DEHP-exposed rats. MEHP-induced disturbance of self-renewal and differentiation was dose-dependent. Moreover, self-renewal proteins were downregulated; the differentiation level was stimulated. Meanwhile, GC-1 proliferation was decreased. Stable transformation strain of wnt10a overexpression GC-1 cell line constructed from lentivirus was utilized in this study. The upregulation of Wnt10a significantly reversed the dysfunction of self-renewal and differentiation and promoted the cell proliferation. Finally, retinol, predicted to be useful in CONNECTIVITY MAP (cMAP), failed to rescue the damage caused by MEHP. Cumulatively, our findings revealed that the downregulation of Wnt10a induced the imbalance of self-renew and differentiation, and inhibition of cell proliferation in GC-1 cells after MEHP exposure.

Gene mutations and chromosomal abnormalities in syndromes with tooth agenesis

This study aims to review the pathogenic mechanisms and clinical manifestations in syndromes with tooth agenesis (TA). Online Mendelian Inheritance in Man and PubMed databases were searched for a comprehensive review. Previous publications reported complicated aetiologies of syndromic TA. Gene mutations in conserved signalling pathways (WNT, EDA, SHH, FGF, and TGF-β/BMP) and crucial molecules (PAX9, PIXT2, IRF6, the p53 family, and subunits of RNA polymerase III) are the main causes of syndromic TA. In the process of odontogenesis, antagonistic or synergistic interactions are demonstrated in patients and murine models. Mutations in some genes (WNT10A, WNT10B, AXIN2, ANTXR1, MSX1, EDA, EDAR, and EDARADD) can result in both syndromic and isolated TA. In addition, chromosomal anomalies are also responsible for syndromic TA (Down syndrome, Wolf-Hirschhorn syndrome, Williams syndrome, and Pierre Robin sequence). The causes and manifestations of syndromic TA are highly complex, and this constitutes a clinical challenge. Mutations in signalling pathways and crucial molecules as well as chromosomal anomalies are responsible for syndromic TA. And there are overlaps between the causative genes of syndromic and isolated TA.

Antunes L, Gabbardo MCL, Silva Barroso de Oliveira D, Sousa-Neto MD, Baratto-Filho F, Küchler EC. The investigation of WNT6 and WNT10A single nucleotide polymorphisms as potential biomarkers for dental pulp calcification in orthodontic patients

The aim of this study is to evaluate if single nucleotide polymorphisms (SNPs) in WNT6 and WNT10A are associated with the risk of dental pulp calcification in orthodontic patients. This cross-sectional study followed the "Strengthening the Reporting of Genetic Association Studies" (STREGA) guidelines. Panoramic radiographs (pre- and post-orthodontic treatment) and genomic DNA from 132 orthodontic patients were studied. Dental pulp calcification (pulp stones and/or pulp space narrowing) was recorded in upper and lower first molars. The SNPs in WNT6 and WNT10A (rs7349332, rs3806557, rs10177996, and rs6754599) were assessed through genotyping analysis using DNA extracted from buccal epithelial cells. The association between pulp calcification and SNPs were analyzed using allelic and genotypic distributions and haplotype frequencies (p<0.05). Prevalence of dental pulp calcification was 42.4% in the 490 studied molars. In the genotypic analysis, the SNPs in WNT10A showed a statistically significant value for molar calcification (p = 0.027 for rs1017799), upper molar calcification (p = 0.040 for rs1017799) (recessive model), and molar calcification (p = 0.046 for rs3806557) (recessive model). In the allelic distribution, the allele C of the SNP rs10177996 in WNT10A was associated with molar calcifications (p = 0.042) and with upper first molar calcification (p = 0.035). Nine combinations of haplotypes showed statistically significant value (p<0.05). The findings of this study indicates that SNPs in WNT10A and WNT6 are associated with dental pulp calcification in molars after orthodontic treatment and may be considered as biomarkers for dental pulp calcification.

Assessing the relationship between single nucleotide polymorphisms in Wingless signaling pathway genes and sella turcica morphology

Sella turcica development involves molecular factors and genes responsible for ossification. It is possible that single nucleotide polymorphisms (SNPs) in key genes are involved in morphological variation of sella turcica. Genes belonging to the WNT signaling pathway are involved in the ossification process and are candidates of sella turcica morphology. This study aimed to evaluate if SNPs in WNT6 (rs6754599) and WNT10A (rs10177996 and rs3806557) genes are associated with the calcification and patterns of the sella turcica. Nonsyndromic individuals were included in the research. Cephalometric radiographs were examined and the sella calcification was evaluated and classified according to the calcification of the interclinoid ligament (no calcification, partial calcification, and incomplete calcification) and sella turcica pattern (normal sella turcica, bridge type A-ribbon-like fusion, bridge type B-extension of the clinoid processes, incomplete bridge, hypertrophic posterior clinoid process, hypotrophic posterior clinoid process, irregularity in the posterior part, pyramidal shape of the dorsum, double contour of the floor, oblique anterior wall, and oblique contour of the floor). DNA samples were used to evaluate SNPs in the WNT genes (rs6754599, rs10177996, and rs3806557) using real-time PCR. Chi-square test or Fisher's exact test were used to compare the allele and genotype distributions according to sella turcica phenotypes. The alpha was set as 5% for all comparisons. A total of 169 individuals were included, 133 (78.7%) present sella turcica partially or completely calcified. Sella turcica anomalies were found in 131 individuals (77.5%). Sella turcica bridge type A (27.8%), posterior hypertrophic clinoid process (17.1%), and sella turcica bridge type B (11.2%) were the most prevalent morphological patterns observed. Individuals carrying the TT genotype in rs10177996 (TT vs. CT + CC) had higher chance to present a partially calcified sella turcica (p = 0.047; Odds ratio = 2.27, Confidence Interval 95% 1.01-5.13). In conclusion, the SNP in WNT10A is associated with the calcification phenotype of the sella turcica, the pleiotropic effect of this gene should be taken into consideration in future studies.

A Genome-wide association study of premolar agenesis in a chinese population

OBJECTIVE

Premolar agenesis is a common subtype of tooth agenesis. Although a genome-wide study (GWAS) has identified some variants involved in tooth agenesis in Europeans, the genetic mutation related to premolar agenesis in the Chinese population remains unclear.

MATERIALS AND METHODS

We present a GWAS in 218 premolar agenesis cases and 1,222 controls using the Illumina Infinium^® Global Screening Array. 5,585,618 single nucleotide polymorphisms (SNPs) were used for tests of associations with premolar agenesis.

RESULTS

Four independent SNPs on chromosome 2 were identified as susceptibility loci, including rs147680216, rs79743039, rs60540881, and rs6738629. The genome-wide significant SNP rs147680216 (p = 6.09 × 10^-9 ) was predicted to change the structure of the WNT10A protein and interact with hedgehog signaling pathway components. Meta-analysis showed that the rs147680216 A allele significantly increased the risk of tooth agenesis (p = 0.000). The other three SNPs with nominal significance are novel susceptibility loci. Of them, rs6738629 (p = 5.40 × 10^-6 ) acts as a potential transcriptional regulator of GCC2, a gene playing a putative role in dental and craniofacial development.

CONCLUSION

Our GWAS indicates that rs147680216 and additional three novel susceptibility loci on chromosome 2 are associated with the risk of premolar agenesis in the Chinese population.

[Common nail diseases in children and adolescents : Recognize, advise, treat]

There are a number of nail diseases that primarily occur in children and adolescents. Many of these nail changes are physiologic and are only transient. Thus, they do not need any therapy. Infectious nail diseases or nail involvement in chronic inflammatory dermatoses can be found in both children and adults, and may require specific treatment. Nail pigmentation such as longitudinal melanonychia occur significantly less frequently in children than in adult patients, and have different causes and a better prognosis. Knowledge about these child-specific peculiarities of nail diseases is necessary in order to provide the best possible advice to parents and to offer appropriate treatment. This article focuses on the most common and important nail diseases in children and adolescents and their treatment.

Rare Genetic Variants in Human APC Are Implicated in Mesiodens and Isolated Supernumerary Teeth

The activation of Wnt/β-catenin signalling is a prerequisite for odontogenesis. APC, a member of the AXIN-CK1-GSK3β-APC β-catenin destruction complex, functions to modulate Wnt/β-catenin signalling to establish regular teeth number and positions. APC loss-of-function mutations are associated with the over-activation of WNT/β-catenin signalling and subsequent familial adenomatous polyposis (FAP; MIM 175100) with or without multiple supernumerary teeth. The ablation of Apc function in mice also results in the constitutive activation of β-catenin in embryonic mouse epithelium and causes supernumerary tooth formation. The objective of this study was to investigate if genetic variants in the APC gene were associated with supernumerary tooth phenotypes. We clinically, radiographically, and molecularly investigated 120 Thai patients with mesiodentes or isolated supernumerary teeth. Whole exome and Sanger sequencing identified three extremely rare heterozygous variants (c.3374T>C, p.Val1125Ala; c.6127A>G, p.Ile2043Val; and c.8383G>A, p.Ala2795Thr) in APC in four patients with mesiodentes or a supernumerary premolar. An additional patient with mesiodens was compound as heterozygous for two APC variants (c.2740T>G, p.Cys914Gly, and c.5722A>T, p.Asn1908Tyr). Rare variants in APC in our patients are likely to contribute to isolated supernumerary dental phenotypes including isolated mesiodens and an isolated supernumerary tooth.

Dental Phenotype with Minor Ectodermal Symptoms Suggestive of WNT10A Deficiency

Ectodermal dysplasias (EDs) represent a heterogeneous group of genetic disorders characterized by the abnormal development of ectodermal-derived tissues. They include the involvement of the hair, nails, skin, sweat glands, and teeth. Pathogenic variants in EDA1 (Xq12-13.1; OMIM*300451), EDAR (2q11-q13; OMIM*604095), EDARADD (1q42-q43, OMIM*606603), and WNT10A (2q35; OMIM*606268) genes are responsible for most EDs. Bi-allelic pathogenic variants of WNT10A have been associated with autosomal recessive forms of ED, as well as non-syndromic tooth agenesis (NSTA). The potential phenotypic impact of associated modifier mutations in other ectodysplasin pathway genes has also been pointed out. We present on an 11-year-old Chinese boy with oligodontia, with conical-shaped teeth as the main phenotype, and other very mild ED signs. The genetic study identified the pathogenic variants WNT10A (NM_025216.3): c.310C > T; p. (Arg104Cys) and c.742C > T; p. (Arg248Ter) in compound heterozygosis, confirmed by parental segregation. In addition, the patient had the polymorphism EDAR (NM_022336.4): c.1109T > C, p. (Val370Ala) in homozygosis, named EDAR370. A prominent dental phenotype with minor ectodermal symptoms is very suggestive of WNT10A mutations. In this case, the EDAR370A allele might also attenuate the severity of other ED signs.

Case report: Two individuals with AEBP1-related classical-like EDS: Further clinical characterisation and description of novel AEBP1 variants

Introduction: AEBP1-related classical-like EDS (clEDS type 2) is a rare type of Ehlers-Danlos syndrome (EDS) that was first reported in 2016. There are overlapping clinical features with TNXB-related classical-like EDS (or clEDS type 1), including skin hyperextensibility, joint hypermobility, and easy bruising. There are currently nine reported individuals with AEBP1-related clEDS type 2. This report confirms previous findings and provides additional clinical and molecular data on this group of individuals. Materials and methods: Two individuals (P1 and P2), with features of a rare type of EDS, were clinically assessed in the London national EDS service and underwent genetic testing. Results: Genetic testing in P1 revealed likely pathogenic AEBP1 variants: c.821del:p. (Pro274Leufs*18) and c.2248T>C:p. (Trp750Arg). In P2 pathogenic AEBP1 variants, c.1012G>T:p. (Glu338*) and c.1930C>T:p. (Arg644*) were identified. Discussion: These two individuals increased the reported number of individuals with AEBP1-related clEDS to 11 (six females and five males). There are shared features with previously reported individuals, including hypermobility (11/11), skin hyperextensibility (11/11), presence of atrophic scarring (9/11), and easy bruising (10/11). In P1, a chronic right vertebral artery dissection, mild dilatation of the splenic artery, aberrant subclavian artery, and tortuous iliac arteries were observed at the age of 63 years. Cardiovascular disease has been reported, including mitral valve prolapse (4/11), peripheral arterial disease (1/11), and aortic root aneurysm requiring surgical intervention (1/11). Hair loss has been reported in 6/11 individuals (five females and one male), only one of which was documented to have a formal diagnosis of androgenetic alopecia, while other individuals were described as having thinning of hair, male pattern hair loss, or unspecified alopecia. Conclusion: The clinical features of individuals with AEBP1-related EDS have not been fully elucidated yet. Hair loss is present in 6/11 individuals with AEBP1-related clEDS and appears to be a feature of this condition. This is the first time hair loss has been formally reported as a characteristic feature in a rare type of EDS. Cardiovascular surveillance seems warranted in this condition because 2/11 individuals have evidence of arterial aneurysm and/or dissection. Further descriptions of affected individuals are necessary to update diagnostic criteria and management guidelines.

Molecular Pathway-Based Classification of Ectodermal Dysplasias: First Five-Yearly Update

To keep pace with the rapid advancements in molecular genetics and rare diseases research, we have updated the list of ectodermal dysplasias based on the latest classification approach that was adopted in 2017 by an international panel of experts. For this purpose, we searched the databases PubMed and OMIM for the term "ectodermal dysplasia", referring mainly to changes in the last 5 years. We also tried to obtain information about those diseases on which the last scientific report appeared more than 15 years ago by contacting the authors of the most recent publication. A group of experts, composed of researchers who attended the 8th International Conference on Ectodermal Dysplasias and additional members of the previous classification panel, reviewed the proposed amendments and agreed on a final table listing all 49 currently known ectodermal dysplasias for which the molecular genetic basis has been clarified, including 15 new entities. A newly reported ectodermal dysplasia, linked to the gene LRP6, is described here in more detail. These ectodermal dysplasias, in the strict sense, should be distinguished from syndromes with features of ectodermal dysplasia that are related to genes extraneous to the currently known pathways involved in ectodermal development. The latter group consists of 34 syndromes which had been placed on the previous list of ectodermal dysplasias, but most if not all of them could actually be classified elsewhere. This update should streamline the classification of ectodermal dysplasias, provide guidance to the correct diagnosis of rare disease entities, and facilitate the identification of individuals who could benefit from novel treatment options.

Dose Dependence Effect in Biallelic WNT10A Variant-Associated Tooth Agenesis Phenotype

The goal of this study was to identify the pathogenic gene variants in patients with odonto-onycho-dermal dysplasia syndrome (OODD) or nonsyndromic tooth agenesis. Four unrelated individuals with tooth agenesis and their available family members were recruited. Peripheral blood was collected from four probands and five family members. Whole-exome sequencing (WES) and Sanger sequencing were used to identify the pathogenic gene variants. The harmfulness of these variations was predicted by bioinformatics. We identified four biallelic variants of the WNT10A gene in four patients, respectively: the proband#660: c.1176C > A (p.Cys392*) and c.812G > A (p.Cys271Tyr); the proband#681: c.637G > A (p.Gly213Ser) and c.985C > T (p.Arg329*); the proband#829: c.511C > T (p.Arg171Cys) and c.637G > A (p.Gly213Ser); and the proband#338: c.926A> G (p.Gln309Arg) and c.511C > T (p.Arg171Cys). Among them, two variants (c.812G > A; p.Cys271Tyr and c.985C > T; p.Arg329*) were previously unreported. Bioinformatics analysis showed that the pathogenicity of these six variants was different. Tertiary structure analysis showed that these variants were predicted to cause structural damage to the WNT10A protein. Genotype−phenotype analysis showed that the biallelic variants with more harmful effects, such as nonsense variants, caused OODD syndrome (#660 Ⅱ-1) or severe nonsyndromic tooth agenesis (NSTA) (#681 Ⅱ-1); the biallelic variants with less harmful effects, such as missense variants, caused a mild form of NSTA (#829 Ⅱ-2 and #338 Ⅱ-1). Individuals with a heterozygous variant presented a mild form of NSTA or a normal state. Our results further suggest the existence of the dose dependence of WNT10A pathogenicity on the tooth agenesis pattern, which broadens the variation spectrum and phenotype spectrum of WNT10A and could help with clinical diagnosis, treatment, and genetic counseling.

Real-World Results from Combined Screening for Monogenic Genomic Health Risks and Reproductive Risks in 300 Adults

New methods and demonstrations of feasibility guide future implementation of genomic population health screening programs. This is the first report of genomic population screening in a primary care, non-research setting using existing large carrier and health risk gene sequencing panels combined into one 432-gene test that is offered to adults of any health status. This report summarizes basic demographic data and analyses patterns of pathogenic and likely pathogenic genetic findings for the first 300 individuals tested in this real-world scenario. We devised a classification system for gene results to facilitate clear message development for our Genomic Medicine Action Plan messaging tool used to summarize and activate results for patients and primary care providers. Potential genetic health risks of various magnitudes for a broad range of disorders were identified in 16% to 34% of tested individuals. The frequency depends on criteria used for the type and penetrance of risk. 86% of individuals are carriers for one or more recessive diseases. Detecting, reporting, and guiding response to diverse genetic health risks and recessive carrier states in a single primary care genomic screening test appears feasible and effective. This is an important step toward exploring an exome or genome sequence as a multi-purpose clinical screening tool.

Keloid: Genetic susceptibility and contributions of genetics and epigenetics to its pathogenesis

Keloid, characterized by fibroproliferative disorders of the skin, can be developed in people of different genders, ages, and ethnicities. Keloid can appear in any part of the body but are especially common on the earlobe, upper torso, and triangular muscle. The genetic heterogeneity and susceptibility of KD (keloid) vary among different races and ethnicities. Studies have found that multiple loci on multiple chromosomes are associated with the pathogenesis of KD, and specific gene variants may also be involved. Despite multiple investigations attempting to uncover the etiology of keloid formation, the genetic mechanism of keloid formation remains unknown. To establish a foundation for a better understanding of the genetics and epigenetics of keloids, we have evaluated and summarized current studies which are mostly related to heredity, genetic polymorphisms, predisposing gene, DNA methylation, and non-coding RNA. We also discussed the problems and potential of genetic and epigenetic investigations of keloids, with the goal of developing new therapeutic approaches to enhance the prognosis of keloid patients.

Identification of a novel missense heterozygous mutation in the KDF1 gene for non-syndromic congenital anodontia

OBJECTIVES

KDF1 is a recently identified gene related to tooth development, but it has been little studied. To date, only three cases have been reported in which KDF1 mutations are related to tooth development, including two ectodermal dysplasia cases accompanied by tooth loss and one non-syndromic case with tooth agenesis. However, no KDF1 mutations have been reported as associated with non-syndromic anodontia. Here, the aim was to investigate the genetic etiology of this condition and explore the functional role of a novel KDF1 mutation in a Chinese patient with non-syndromic anodontia.

MATERIALS AND METHODS

Pathogenic variants were identified by whole-exome and Sanger sequencing. Meanwhile, we conducted a literature review of the reported KDF1 mutations and performed an in vitro functional analysis of four anodontia-causing KDF1 mutations (one novel and three known).

RESULTS

We identified a novel de novo missense mutation (c.911 T > A, p.I304N) in the KDF1 gene in a Chinese patient with severe non-syndromic anodontia. In vitro functional studies showed altered mRNA and protein expression levels of the mutant KDF1.

CONCLUSIONS

Our results are the first report of KDF1 missense mutation causing non-syndromic anodontia.

CLINICAL RELEVANCE

This study not only further supports the important role of KDF1 in non-syndromic congenital anodontia, but also expands the spectrum of KDF1 mutations and will contribute to the genetic diagnosis and counselling of families with anodontia.

Novel Dental Anomaly-associated Mutations in WNT10A Protein Binding Sites

OBJECTIVE

WNT/β-catenin signaling is initiated by binding of a WNT protein to a Frizzled (FZD) receptor and a co-receptor, low-density lipoprotein (LDL) receptor-related protein 5 or 6 (LRP5/6). The objective of this study was to find the genetic variants responsible for dental anomalies found in 4 families.

METHODS

Clinical and radiographic examination and whole exome sequencing were performed on 5 patients affected with dental anomalies and the mutant proteins modeled.

RESULTS

Five patients were heterozygous for the WNT10A variants, including c.877C>T; p.Arg293Cys, c.874A>G; p.Ser292Gly, c.1042C>T; p.Arg348Cys, and c.1039G>T; p.347GluX. The p.Arg293Cys and p.Ser292Gly mutations are located in the WNT10A N-terminal domain region with binding sites for FZD receptor, porcupine, WNTLESS, and extracellular binding proteins, so they are likely to have adverse effects on binding these proteins. The p.Arg348Cys mutation, which is located in the binding site of LRP5/6 co-receptors, is postulated to result in impaired binding to these co-receptors. The nonsense mutation p.347GluX is predicted to result in the truncation of most of the C-terminal domain, which is likely to disrupt the binding of WNT10A to WNTLESS, the membrane protein that binds lipid-acylated WNT proteins to carry them from the endoplasmic reticulum to the cell surface and FZD.

CONCLUSIONS

Four novel mutations in WNT10A were identified in patients with isolated tooth agenesis. The mutations in the N-terminal domain and the interface between the N- and C-terminal domains of WNT10A in our patients are likely to disrupt its binding with FZD, LRP5/6, and various other proteins involved in WNT10A processing and transport, impair WNT and SHH signaling, and subsequently result in tooth agenesis, microdontia, and root maldevelopment.

Diffuse Large B-Cell Lymphoma Promotes Endothelial-to-Mesenchymal Transition via WNT10A/Beta-Catenin/Snail Signaling

Diffuse large B-cell lymphoma (DLBCL) is one type of highly heterogeneous lymphoid malignancy with 30%~40% of patients experiencing treatment failure. Novel risk stratification and therapeutic approaches for DLBCL are urgently needed. Endothelial-to-mesenchymal transition (EndMT), which contributes to tumor angiogenesis, metastasis, drug resistance, and cancer-associated fibroblast generation, has been detected in the microenvironment of many types of cancers. However, the existence of EndMT in the hematological malignancies microenvironment remains unknown. Here, we identified the existence of EndMT in DLBCL-associated endothelial cells and the clinical relevance of EndMT markers in DLBCL, which was associated with advanced clinical stage and poor prognosis. In vitro experiments confirmed that DLBCL cells stimulated angiogenesis and EndMT of human umbilical vein endothelial cells (HUVECs). We further unveiled the molecular mechanisms underlying this process. We demonstrated that WNT10A, a WNT family member overexpressed in DLBCL tissues and correlated with clinical features in DLBCL, promoted EndMT through glycogen synthase kinase 3β (GSK3β)/β-catenin/snail signaling. WNT10A inhibited the binding of GSK3β to β-catenin/snail, resulting in β-catenin and snail nuclear accumulation and target gene transcription. Silencing β-catenin and snail respectively attenuated WNT10A-induced angiogenesis and EndMT. The interplay between β-catenin-dependent and snail-dependent signaling was also confirmed in this study. Collectively, these findings identified that WNT10A/GSK3β/β-catenin/snail pathway performed vital roles in DLBCL-induced EndMT and indicated that EndMT markers and WNT10A may serve as novel predictors of clinical outcome.

Long Non-Coding RNAs MALAT1 and NEAT1 in Non-syndromic Orofacial Clefts

Long non-coding RNAs (lncRNAs) are thought to play important roles in non-syndromic orofacial clefts (NSOFC). Clinical diagnosis was categorized as either non-syndromic cleft lip with or without cleft palate (NSCL/P), or non-syndromic cleft palate-only (NSCPO). Tissues excised from the trimmed wound edge were reserved as experimental samples; adjacent normal control was used as a positive control, and tissue from healthy individuals was used as a blank control. Target lncRNAs in the collected tissues were identified using microarrays and quantitative reverse transcription PCR (RT-qPCR). Immunohistochemical (IHC) staining and RT-qPCR were used to verify the target mRNAs. Pathway, gene ontology (GO) enrichment, and TargetScan predictions were employed to construct competing endogenous RNA networks (ceRNA networks) and explore their potential functions. RNA-Seq revealed 24 upregulated and 43 downregulated lncRNAs; MALAT1 and NEAT1 were screened and validated using RT-qPCR. Common NSOFC risk factors were positively correlated with MALAT1 and NEAT1 expression. Bioinformatics predicted four ceRNA networks; GO enrichment focused on their potential functions. RT-qPCR and IHC data were consistent with respect to expression levels of proteins and the mRNAs that encode them. As MALAT1 and NEAT1 are associated with the severity of NSOFC, they represent potential therapeutic targets and prognostic biomarkers.

MiR-19 3b regulated the formation of coat colors by targeting WNT10A and GNAI2 in Cashmere goats

MiRNAs as a series of small noncoding RNAs that play a crucial part in regulating coat color and hair follicle development. In the previous Solexa sequencing experiments, there were many miRNAs expressed differentially in alpacas with different coat color, including miR-193b.But the mechanism of miR-193b in mammalian pigmentation is still unknown. In this study, bioinformatics analysis showed that WNT10A and GNAI2 might be the target genes of miR-193b. qRT-PCR showed the expression of miR-193b in white Cashmere goats' skins was obviously lower than that in browns, and the expression of WNT10A and GNAI2 were similar with miR-193b. The protein levels of WNT10A and GNAI2 indicated the same findings. Furthermore, the expression of WNT10A and GNAI2 in keratinocytes were analyzed from mRNA and protein levels, the results manifested that the group of overexpression of miR-193b in HaCaT cells increased the expressions of target genes, and miR-193b inhibition group reduced expressions. Luciferase report assays confirmed that the targeting relationship between miR-193b and target genes (WNT10A and GNAI2), the results showed that miR-193b was positively correlated with target genes. These experimental data showed that miR-193b might participate in adjustment of coat color in skin tissue of Cashmere goat by targeting WNT10A and GNAI2.