A Novel Ectodysplasin a Gene mutation of X-Linked Hypohidrotic Ectodermal Dysplasia.

Introduction: Hypohidrotic ectodermal dysplasia (HED) is a genetic disorder that influences structures of ectodermal origin, such as teeth, hair, and sweat glands. Compared with autosomal recessive and dominant modes of inheritance, the X-linked HED (XLHED) characterized by Hypodontia/Oligodontia teeth, Absent/sparse hair, Anhidrosis/hypohidrosis, and characteristic facial features, is the most frequent and its primary cause is the mutation of ectodysplasin A (EDA) gene. This research aimed to expound the clinical and molecular features of a Chinese male with XLHED and to summarize and compare several previous findings. Methods: Genomic DNA was obtained from the peripheral blood of the proband and his family members, then Sanger sequencing was used to perform a mutational analysis of EDA. Real-time quantitative PCR and Western blotting were used to detect EDA expression. The transcriptional activity of NF-κB was detected using a luciferase assay. Results: The probandwith XLHED was identified a novel EDA mutation, c.1119G>C(p.M373I), that affected the molecular analysis of transmembrane protein exon8 mutations, inherited from the mother. He showed a severe multiple-tooth loss, with over 20 permanent teeth missing and sparse hair and eyebrows, dry, thin, and itching skin. Furthermore, his sweating function was abnormal to a certain extent. Discussion: The functional study showed that this novel mutant led to a significant decrease in the EDA expression level and transcriptional activity of NF-κB. Our findings extend the range of EDA mutations in XLHED patients, which provides the basis and idea for further exploring the pathogenesis of XLHED.

Botanical extract combined with minoxidil improve hidrotic ectodermal dysplasia caused by p.G11R mutations: a case report.

PURPOSE: We aim to explore a potential treatment strategy for hair loss. MATERIALS AND METHODS: A male 6-year-old child was diagnosed with hidrotic ectodermal dysplasia 2 (HED2) caused by GJB6 (p.G11R) mutations. He presented at our clinic with diffuse thinning and fine and brittle hair since birth. Additionally, the child exhibited abnormal development of teeth, fingernails, and toenails. The condition of the child's hair had not improved significantly with age. He was treated with botanical extracts combined with Minoxidil. RESULTS: After one and a half months of treatment, the patient showed remarkable hair growth. CONCLUSIONS: Our team has previously used botanical extracts in combination for the treatment of autosomal recessive wooly hair in children. In the present case, treatment with botanical extract combined with minoxidil was found to be equally efficacious. This case report provides valuable information for future studies on the use of botanical extracts in treating hair loss, as well as a safe and effective potential treatment strategy for children with congenital alopecia.

Ectodermal dysplasia and cholesteatoma: A cross-sectional analysis of otologic issues.

OBJECTIVES: Previous studies have also associated cleft palate with increased cholesteatoma risk. Despite this close relation, the incidence of cholesteatoma and associated otologic issues in patients with ectodermal dysplasia types highly associated with cleft palate (EDT-ACPs) has not been formally analyzed. This study provides insight to guide clinicians caring for patients with ED types associated with cleft palate. METHODS: Individuals with TP63 disorders and Goltz syndrome/Focal Dermal Hypoplasia in the National Foundation for Ectodermal Dysplasia database were contacted for participation in an online REDCap survey from Sept-Dec '22. Descriptive statistics were generated using SAS JMP Pro 17 statistical software. RESULTS: 65 individuals participated in the survey (response rate approx. 18 %). The median [IQR] age was 22 [14, 43], 41 (63 %) were female, and Ectrodactyly-Ectodermal Dysplasia-Cleft Lip/Palate Syndrome (EEC) was most common (n = 26, 40 %). We found that, among our respondents with a history of cleft palate, the incidence of cholesteatoma was 39 %. Among respondents without a history of cleft palate, the incidence of cholesteatoma was 13 % CONCLUSIONS: Otologic issues, such as cholesteatoma, can have permanent implications including hearing loss that can be minimized by early identification and treatment. The estimated incidence of cholesteatoma among our participants is far above the estimated incidence of cholesteatoma in the general population with and without a history of cleft palate, suggesting an independent contribution of EDT-ACPs to the risk of cholesteatoma.

Christ-Siemens-Touraine Syndrome: A Report of a Rare Pediatric Case.

Anhidrotic ectodermal dysplasia (AED), or Christ-Siemens-Touraine syndrome, is an X-linked recessive dermatosis. Rare in incidence, it affects 1 in 100,000 births, mostly boys. Through this observation, we detail the clinical signs that led us to suspect the diagnosis, how this pathology was confirmed, and the therapeutic management we carried out. We present a case of a 10-month-old boy presenting with altered manifestations affecting almost all the ectodermal structures like skin, hair, nails, teeth, sebaceous glands, sweat glands, and tear glands. He also had complete anodontia and a dry mouth. A multidisciplinary treatment was given to the patient with the collaboration of various health professionals. Although Christ-Siemens-Touraine syndrome is a rare condition, it is vital to recognize it early to improve care and prognosis for these patients, while mitigating the psychological impact of the condition on both children and parents.

Improving the Quality of Life in Patients With Hypohidrotic Ectodermal Dysplasia: A Holistic Approach.

Hypohidrotic ectodermal dysplasia (HED), often referred to as Christ-Siemens-Touraine syndrome, is an uncommon inherited genetic disorder characterized by irregularities in structures derived from the ectoderm, such as skin, hair, nails, teeth, and sweat glands. Common manifestations include thin hair, absent teeth (hypodontia) often pointed in shape, and diminished ability to sweat (hypohidrosis). Changes in the ectodysplasin A (EDA) gene are associated with the development of HED. Addressing this condition requires an integrated, interdisciplinary strategy to ensure the best possible support for individuals impacted. This case highlights the significance of early detection, collaborative care, and targeted interventions in managing HED. Continued research is crucial for creating novel therapies and enhancing life quality for those living with this rare condition. Here, we discuss a 22-year-old male patient displaying features such as hypodontia, sparse hair (hypotrichosis), irregular beard growth, a nasal deformity, and an inability to sweat (anhidrosis), which is associated with increased body temperature.

Ectodermal Dysplasia - An Overview and Update.

Ectodermal dysplasias are a heterogeneous group of disorders that are characterized by abnormal development of ectodermal structures like hair, teeth, nails, and sweat glands. Alhough they were earlier classified according to the structures affected and hence the clinical manifestations, recent developments inch towards a genetic basis for classification. They are currently divided into four groups of disorders based on the pathway involved, which includes the ectodysplasin/nuclear factor-kappa B (NFKB) pathway, wingless-type MMTV integration site family, member 10 ([wingless related integration site] WNT10), tumor protein p63 (TP63), and the structural group. In spite of attempts at the segregation of the various disorders, there is a great degree of overlap in clinical features among the conditions, which makes a thorough history-taking and clinical examination important in helping us arrive at a diagnosis and judge the various systems involved. A multidisciplinary approach forms the crux of the management of patients with ectodermal dysplasias and their families, with a focus on education, counseling, prosthesis, and an overall rehabilitative outlook. Special attention must also be paid to screening family members for varying severities of the disorders, and an attempt must be made at a genetic diagnosis with genetic counseling.

Like Father, Like Daughter - Ectodermal Dysplasia-Syndactyly Syndrome: A Case Report.

Ectodermal dysplasia-syndactyly syndrome 1 (EDSS1) is an exceedingly rare condition associated with mutations in the PVL4 gene. It is characterised by sparse, brittle hair, eyebrows and eyelashes, abnormal dentition and nails, along with bilateral cutaneous syndactyly involving the fingers and toes. We report a 2-year-old girl who presented to us with bilateral complete simple syndactyly of the third and fourth web spaces of the hands, along with bilateral syndactyly of both feet involving the second to fourth toes. Upon examination, sparse hair and eyebrows, along with abnormal dentition, were noted. Thorough clinical examination and genetic analysis were conducted on the affected child and her father, who exhibited similar clinical features. Genetic analysis revealed a homozygous nonsense mutation in the PVL4 gene in both individuals. According to the literature, EDSS1 has been reported in only 10 families worldwide, and there are no reported cases from India. Level of Evidence: Level V (Therapeutic).

Dental implants in patients with ectodermal dysplasia: a computer guided quad zygomatic case report and literature review / Implantes dentales en pacientes con displasia ectodérmica: Reporte de caso y revisión de literatura

Abstract Ectodermal dysplasia (ED) is a genetic disorder affecting anatomical structures with an ectodermal origin. The consequent alveolar bone anomalies and lack of teeth require a multidisciplinary approach to rehabilitate patients function and esthetics. To avoid bone grafting procedures the application of zygomatic implants was suggested for the upper jaw treatment. The advancements in three-dimensional (3D) radiology and the introduction of digital implant planning software could enhance the approach to zygomatic implants in ED patients. The present case report describes the quad zygomatic implant treatment of the edentulous maxilla of an ED patient by means of computer guided implant surgery. The patient reported previous failure of bone grafting procedures in the upper jaw. The implants were immediately loaded with a screw-retained complete-arch resin prosthesis. The patient was followed up for 1 year with no biological nor mechanical complications reported, but a slight bone resorption in the anterior zone was observed. Zygomatic implants could be a potential alternative treatment to bone grafting in upper jaw and the digital implant planning could enhance the surgical procedure.

Resumen La displasia ectodérmica (DE) es una enfermedad genética que afecta las estructuras anatómicas de origen ectodérmico. Las consiguientes anomalías del hueso alveolar y la anodoncia requieren un planteamiento multidisciplinario para rehabilitar la función y la estética de los pacientes. Para evitar procedimientos de injerto óseo se sugirió la aplicación de implantes cigomáticos para el tratamiento del maxilar superior. Los avances en radiología tridimensional (3D) y la introducción de software de planificación de implantes digitales podrían mejorar el enfoque de los implantes cigomáticos en los pacientes con displasia ectodérmica. El presente reporte de caso describe el tratamiento con implantes cigomáticos en el maxilar superior edéntulo de un paciente con displasia ectodérmica mediante cirugía de implantes guiada por ordenador. El paciente refirió fracaso de procedimientos de injerto óseo en el maxilar superior. Los implantes se cargaron inmediatamente con una prótesis de resina de arcada completa. El paciente ha sido incluido en un programa de control postoperatorio por 1 año, sin reportarse complicaciones ni biológicas ni mecánicas, siendo el único problema encontrado una ligera reabsorción ósea en la zona anterior. Los implantes cigomáticos podrían ser un posible tratamiento alternativo al injerto óseo en el maxilar superior y la planificación de implantes digitales podría mejorar el procedimiento quirúrgico.

Clinical presentation and genetics of tricho-rhino-phalangeal syndrome (TRPS) type 1: A single-center case series of 15 patients and seven novel TRPS1 variants.

Tricho-rhino-phalangeal syndrome (TRPS) is a rare malformation syndrome characterized by distinctive facial, ectodermal, and skeletal features. TRPS is divided into TRPS type I/III caused by pathogenic variants in TRPS1 and TRPS type II caused by contiguous gene deletions also spanning EXT1 and RAD21. Due to its rarity, knowledge of the clinical course of TRPS remains limited. Therefore, we collected and characterized a case series of 15 TRPS type I patients (median age at diagnosis 15 [interquartile range: 10-18] years, 11 females [73%]) seen at Aarhus University Hospital, Denmark, with a median follow-up period of 10 years. We estimated a minimum point prevalence of 0.5 in 100,000 (95% CI: 0.3-0.8 per 100,000) persons. Common craniofacial features included fine and sparse hair with a high anterior hairline, eyebrows with lateral thinning and a thicker medial part, prominent ears, a bulbous nose tip with small nasal alae, a low-hanging, and often wide columella, and a long philtrum with a thin upper vermillion. Specific skeletal features included short stature and deviating and short fingers with cone-shaped epiphyses and shortened metacarpals on radiographs. The most significant morbidity of the cohort was joint complaints, which were reported by all patients, often already before the TRPS diagnosis was established. We identified ten different TRPS1 variants including both frameshift/nonsense, missense, and splice-site variants, including seven variants not previously reported in the literature. In accordance with previous literature, no genotype-phenotype correlation was identified. The clinical trajectories were heterogeneous involving pediatrics, dermatology, orthopedic surgery, clinical genetics, and/or odontology, emphasizing that close multidisciplinary collaboration is essential for early diagnosis of TRPS and to ensure proper and timely patient care and counseling.

PRKD1-related telangiectasia-ectodermal dysplasia-brachydactyly-cardiac anomaly syndrome: Case report and review of the literature.

Telangiectasia-ectodermal dysplasia-brachydactyly-cardiac anomaly (TEBC) syndrome is a rare autosomal dominant condition, recently linked to the protein kinase D1 (PRKD1) gene. The phenotype of TEBC remains incomplete at this point. Our aim is to improve the characterization of the clinical and molecular aspects of the TEBC syndrome. We report on the 8th patient carrying a heterozygous de novo variation of PRKD1 c.2134G > A, p. (Val712Met) identified by trio exome sequencing. The proband presents with partial atrioventricular septal defect, brachydactyly, ectodermal dysplasia, telangiectasia that developed in childhood, intellectual disability with microcephaly, multicystic renal dysplasia and moderate hormonal resistance. In view of this 8th description and review of the literature, it appears that neurodevelopmental disorders and microcephaly are frequently associated with PRKD1 missense variants, adding to the four main clinical signs described initially in the TEBC syndrome. Further descriptions are required to confirm the observed endocrine and kidney abnormalities. This should contribute to a more comprehensive understanding of the phenotypic spectrum and may help establish genotype-phenotype correlations. In the context of genotype-first strategy, accurate patient descriptions are fundamental. Characterization of specific syndromic associations is essential for variant interpretation support and patient follow-up, even in very rare diseases, such as the TEBC syndrome.

Punctal Atresia As a Clinical Indicator of Systemic Genetic Anomalies.

BACKGROUND: Punctal atresia or agenesis (PA) is a rare congenital anomaly characterized by the absence or closure of the tear duct puncta, potentially linked to systemic genetic anomalies. The necessity of a genetic workup based solely on the presence of PA remains uncertain. This study investigates a cohort of PA patients, examining the prevalence and types of associated syndromes. METHODS: A retrospective medical records review of all patients diagnosed with PA at the Children's Hospital of Philadelphia between 2009-2023 was conducted, analyzing medical histories and genetic testing results. Primary outcomes included the prevalence of systemic syndromes, while secondary outcomes focused on the variety of associated syndromes. RESULTS: Forty-four patients were included, of which 31 were male (70%) with a mean ± SD age 3.3 ± 3.3 years. Overall, 87 puncta in the study cohort were affected, and 26 cases (59%) were bilateral. Systemic abnormalities or genetic syndromes were identified in 19 patients (43%), with the most common being Ectodermal Dysplasia and Down syndrome. Additional rare syndromes were demonstrated. No significant association was found between systemic abnormalities and gender, bilaterality, or the number of puncta involved. CONCLUSIONS: A high incidence of systemic syndromes (43%) was observed in the study cohort. In individuals with PA who also exhibit extraocular disease, systemic evaluation and genetic workup should be considered. Syndromic diagnoses identified in our cohort also include: Branchio-oto-renal syndrome, 22q11.2 deletion syndrome, 1q21.1 microdeletion syndrome, NF1, monosomy 4q and trisomy 6q, which represent novel associations. The lack of correlation between PA's phenotypic severity and systemic abnormalities highlights the need to obtain a comprehensive medical history and consider a systemic workup in PA patients.

Three-Dimensional Modeling and Quantitative Assessment of Mandibular Volume in Ectodermal Dysplasia: A Case Series.

Background and Objectives: Ectodermal dysplasia (ED)-a genetic disorder-is characterized by severe tooth deficiency. We compared the mandibular volume and the sagittal and horizontal mandibular widths between patients with ED (ED group) and individuals without tooth deficiency (control group) using three-dimensional modeling. We hypothesized that the mandibular volume differs in ED cases owing to congenital tooth deficiency. Materials and Methods: We used previously obtained cone-beam computed tomography (CBCT) images of 13 patients with ED. The control group data comprised retrospective CBCT images of patients of similar age and sex with a skeletal relationship of class 1. Further, using the three-dimensional image analysis software, the tooth crowns were separated from the mandible, the mandible was reconstructed and the gonion-to-gonion distance in the mandible was marked, the distance to the menton point was measured, and the distance between the two condyles was measured and compared with the control group. Results: Overall, 46.2% and 53.8% of the participants were men and women, respectively. In the ED group, the mean age of the participants was 15.46 (range, 6-24) years, and the mean number of mandibular teeth was 4.62. Notably, the edentulous mandible volume of the ED group (27.020 mm3) was statistically significantly smaller than that of the control group (49.213 mm3) (p < 0.001). There was no difference between the two groups in terms of the marked points. For data analysis, the Shapiro-Wilk test, independent samples t-test, and Mann-Whitney U test were used. Conclusions: It has been considered that mandible volume does not develop in ED cases because of missing teeth. Modern practices, such as the CBCT technique and three-dimensional software, may be effective in identifying the true morphologic features, especially in patients with genetic syndromes affecting the maxillofacial structure.

Tooth agenesis related to a novel KDF1 variant: A case report and literature review.

OBJECTIVES: To investigate the role of Keratinocyte Differentiation Factor 1 (KDF1) in ectodermal dysplasia (ED) and nonsyndromic tooth agenesis (NSTA) and perform a literature review. METHODS: Genome sequencing was used to identify genetic variants in a Thai, NSTA proband and validated through Sanger sequencing. Pathogenicity was assessed using ACMG guidelines, MetaRNN and AlphaMissense. A comprehensive review of KDF1/NSTA cases informed genotype-phenotype analysis of the proband. RESULTS: The proband revealed multiple missing teeth, caries and extensive periodontal disease. Deep phenotyping showed no signs of ED beyond tooth agenesis. The identified novel KDF1 variant, p.Ile243Leu, was classified as 'likely pathogenic' by ACMG and predicted as 'detrimental' by MetaRNN and AlphaMissense analyses. A total of 14 reviewed KDF1 cases revealed ED-associated variants (3 variants in 8 patients) clustering in the region of amino acids 251-275, within the DUF4656 domain, while NSTA-causing variants (4 variants in 6 patients) were typically found in amino- or carboxy-termini to this region. KDF1/NSTA cases exhibited an average of 15 missing teeth, with a higher prevalence in the mandible. CONCLUSION: This study identifies a novel KDF1 variant-related NSTA in Thai people. The genotype-phenotype correlates suggest a distinctive pattern and tooth agenesis of KDF1-related NSTA.

Intubation in a Case of Ectodermal Dysplasia During Surgery: A Case Report.

Ectodermal dysplasia, a heterogeneous group of rare genetic disorders, is characterized by the aberrant development of ectodermal structures, leading to various clinical anomalies. This case report presents a unique and challenging case of a 33-year-old male with ectodermal dysplasia who underwent Le Fort III advancement and implant rehabilitation surgery to address severe craniofacial and dental deficiencies. This case, characterized by facial dysmorphism, craniofacial anomalies, and the absence of a nasal bone, highlights the complexity of surgical planning required to address these diverse clinical features. The crucial element of this report is the innovative approach to airway management through trans mylohyoid/submental intubation, which successfully navigated the patient's aberrant anatomy. Multidisciplinary collaboration played a pivotal role in achieving a holistic and patient-centered approach. By sharing this case, we aim to provide insights into the nuances of managing complex patients with ectodermal dysplasia, emphasizing the importance of individualized care, innovative techniques, and interdisciplinary teamwork to optimize patient outcomes and contribute to advancing medical knowledge.

Bart syndrome: A case report of neonatal disorder.

Bart Syndrome, characterized by congenital skin absence, blistering, and nail abnormalities, presents complex neonatal challenges. This rare condition demands a multidisciplinary approach for accurate diagnosis and comprehensive care.

The oligodontia phenotype in a X-linked hypohidrotic ectodermal dysplasia patient with a novel EVC2 variant.

Objectives: To analyse the pathogenic genes in a patient with hypohidrotic ectodermal dysplasia (HED) and explore the relationship between pathogenic genes and the oligodontia phenotype. Methods: Clinical data and peripheral blood were collected from a patient with HED. Pathogenic genes were analysed by whole-exon sequencing (WES) and verified by Singer sequencing. The secondary and tertiary structures of the variant proteins were predicted to analyse their toxicity. Results: The patient exhibited a severe oligodontia phenotype, wherein only two deciduous canines were left in the upper jaw. WES revealed a hemizygous EDA variant c.466C > T p.(Arg156Cys) and a novel heterozygous EVC2 variant c.1772T > C p.(Leu591Ser). Prediction of the secondary and tertiary structures of the EDA variant p.(Arg156Cys) and EVC2 variant p.(Leu591Ser) indicated impaired function of both molecules. Conclusion: The patient demonstrated a more severe oligodontia phenotype when compared with the other patients caused by the EDA variant c.466C > T. Since Evc2 is a positive regulator of the Sonic Hedgehog (Shh) signal pathway, we speculated that the EVC2 variant p.(Leu591Ser) may play a synergistic role in the oligodontia phenotype of HED, thereby exacerbating the oligodontia phenotype. Knowledge of oligodontia caused by multiple gene variants is of great significance for understanding individual differences in oligodontia phenotypes.

Activation of wnt/ß-catenin signaling pathway down regulated osteogenic differentiation of bone marrow-derived stem cells in an anhidrotic ectodermal dysplasia patient with EDA/EDAR/EDARADD mutation.

Objective: To explore the mechanism by which the Wnt/ß-catenin pathway induces osteogenic differentiation of bone marrow-derived stem cells (BMSCs) in anhidrotic ectodermal dysplasia (AED) with an Ectodysplasin A (EDA)/EDA receptor (EDAR)/EDARADD mutation. Methods: An AED patient served as the AED group, whereas the other patients without AED were included in the normal group. Peripheral venous blood collected from the AED patient was subjected to whole-genome resequencing. BMSCs from the mandible of patients with AED and normal individuals were isolated and cultured in vitro. Cell proliferation assay was performed to compare the growth speed of BMSCs between the AED and normal groups. CHIR-99021, an activator of the Wnt/ß-catenin pathway and XAV-939, an inhibitor, was used to manage BMSCs in an osteogenic environment in both groups. The expression of ß-catenin was detected by quantitative polymerase chain reaction, while that of RUNX2 was detected by western blotting. Alizarin red was used for staining. Results: A novel mutation (c.152T > A in EDA) and two known mutations (c.1109T > C in EDAR and c.27G > A in EDARADD) were identified. The growth rate in the normal group was higher than that in the AED group. In the normal group, the number and size of calcified nodes and the expression of RUNX-2 increased with CHIR-99021 treatment, which could be inhibited by XAV-939. In contrast, CHIR-99021 inhibited osteogenesis in the AED group and this effect was promoted by XAV-939. Conclusion: Activation of the Wnt/ß-catenin pathway downregulates osteogenesis of BMSCs in AED patients with EDA/EDAR/EDARADD gene mutations. Further investigation in more AED patients is required, given the wide range of mutations involved in AED.

Compound heterozygous WNT10A missense variations exacerbated the tooth agenesis caused by hypohidrotic ectodermal dysplasia.

BACKGROUND: The aim of this study was to analyse the differences in the phenotypes of missing teeth between a pair of brothers with hypohidrotic ectodermal dysplasia (HED) and to investigate the underlying mechanism by comparing the mutated gene loci between the brothers with whole-exome sequencing. METHODS: The clinical data of the patients and their mother were collected, and genomic DNA was extracted from peripheral blood samples. By Whole-exome sequencing filtered for a minor allele frequency (MAF) ≤0.05 non-synonymous single-nucleotide variations and insertions/deletions variations in genes previously associated with tooth agenesis, and variations considered as potentially pathogenic were assessed by SIFT, Polyphen-2, CADD and ACMG. Sanger sequencing was performed to detect gene variations. The secondary and tertiary structures of the mutated proteins were predicted by PsiPred 4.0 and AlphaFold 2. RESULTS: Both brothers were clinically diagnosed with HED, but the younger brother had more teeth than the elder brother. An EDA variation (c.878 T > G) was identified in both brothers. Additionally, compound heterozygous variations of WNT10A (c.511C > T and c.637G > A) were identified in the elder brother. Digenic variations in EDA (c.878 T > G) and WNT10A (c.511C > T and c.637G > A) in the same patient have not been reported previously. The secondary structure of the variant WNT10A protein showed changes in the number and position of α-helices and ß-folds compared to the wild-type protein. The tertiary structure of the WNT10A variant and molecular simulation docking showed that the site and direction where WNT10A binds to FZD5 was changed. CONCLUSIONS: Compound heterozygous WNT10A missense variations may exacerbate the number of missing teeth in HED caused by EDA variation.

Eight EDA mutations in Chinese patients with tooth agenesis and genotype-phenotype analysis.

OBJECTIVE: Tooth agenesis is a common craniofacial malformation, which is often associated with gene mutations. The purpose of this research was to investigate and uncover ectodysplasin A (EDA) gene variants in eight Chinese families affected with tooth agenesis. METHODS: Genomic DNA was extracted from tooth agenesis families and sequenced using whole-exome sequencing. The expression of ectodysplasin A1 (EDA1) protein was studied by western blot, binding activity with receptor was tested by pull-down and the NF-κB transcriptional activity was analyzed by Dual luciferase assay. RESULTS: Eight EDA missense variants were discovered, of which two (c.T812C, c.A1073G) were novel. The bioinformatics analysis indicated that these variants might be pathogenic. The tertiary structure analysis revealed that these eight variants could cause structural damage to EDA proteins. In vitro functional studies demonstrated that the variants greatly affect protein stability or impair the EDA-EDAR interaction; thereby significantly affecting the downstream NF-κb transcriptional activity. In addition, we summarized the genotype-phenotype correlation caused by EDA variants and found that EDA mutations leading to NSTA are mostly missense mutations located in the TNF domain. CONCLUSION: Our results broaden the variant spectrum of the EDA gene associated with tooth agenesis and provide valuable information for future genetic counseling.

A spectrum of TP63-related disorders with eight affected individuals in five unrelated families.

TP63-related disdorders broadly involve varying combinations of ectodermal dysplasia (sparse hair, hypohydrosis, tooth abnormalities, nail dysplasia), cleft lip/palate, acromelic malformation, split-hand/foot malformation/syndactyly, ankyloblepharon filiforme adnatum, lacrimal duct obstruction, hypopigmentation, and hypoplastic breasts and/or nipples. TP63-related disorders are associated with heterozygous pathogenic variants in TP63 and include seven overlapping phenotypes; Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC), Ectrodactyly-ectodermal dysplasia-cleft lip/palate syndrome 3 (EEC3), Limb-mammary syndrome (LMS), Acro-dermo-ungual-lacrimal-tooth syndrome (ADULT), Rapp-Hodgkin syndrome (RHS), Split-hand/foot malformation 4 (SHFM4), and Orofacial cleft 8. We report on five unrelated families with 8 affected individuals in which the probands presented with varying combinations of ectodermal dysplasia, cleft lip/palate, split-hand/foot malformation, lacrimal duct obstruction, and ankyloblepharon filiforme adnatum. The clinical diagnosis involved AEC syndrome (2 patients), EEC3 syndrome (2 patients), and a yet hitherto unclassified TP63-related disorder. Sanger sequence analysis of the TP63 gene was performed revealing five different variants among which four were novel and three were de novo. The identificated TP63 variants co-segregated with the other affected individuals in the families. The abnormalities of ectoderm derived structures including hair, nails, sweat glands, and teeth should alert the physician to the possibility of TP63-related disorders particularly in the presence of orofacial clefting.