Zimmermann-Laband syndrome associated with a balanced reciprocal translocation t(3;8)(p21.2;q24.3) in mother and daughter: molecular cytogenetic characterization of the breakpoint regions

Zimmermann-Laband syndrome-associated hereditary gingival fibromatosis

Hereditary gingival fibromatosis (HGF) is an uncommon slow-growing fibrous overgrowth characterized by connective tissue accumulation. It presents as an isolated feature or as a manifestation of any syndrome. Various syndromes associated with HGF are inherited by autosomal dominant/recessive/X-linked traits. Zimmermann-Laband syndrome (ZLS) is a rare, autosomal dominant inherited disease manifested with gingival fibromatosis (GF), nose and ears abnormalities, and hypoplastic/dysplastic nails or terminal phalanges of hand and feet. Although the pattern of inheritance was found to be both autosomal dominant and recessive traits, the molecular basis is still unclear. This report presents a possible case of ZLS-associated HGF in a 25-year-old female patient who presents with GF, hypertrichosis, and other syndrome-related features. Her father was similarly affected whereas her mother and sibling were asymptomatic. The patient and her family members were explained about the condition and surgical periodontal therapy was carried out for the patient to improve esthetics and was followed up regularly. Esthetics was significantly improved and no recurrence was noted at the end of 6 months.

Dental anomalies in syndromes displaying hypertrichosis in the clinical spectrum

Hypertrichosis and dental anomalies may occur alone or in combination in the spectrum of many syndromes. To identify genetic entities characterized by hypertrichosis and dental anomalies, a search was performed in the Mendelian Inheritance in Man database with the terms "hypertrichosis" or "hirsutism" and "tooth" or "dental abnormalities." Nondependent androgen metabolism disturbances were classified as hypertrichosis. Genetic entities with hypertrichosis and dental anomalies were included in the study. Additional searches were performed in the PubMed and Orphanet databases, when necessary, in order to include data from scientific articles. An integrative analysis of the genes associated with the identified syndromes was conducted using STRING to characterize biological processes, pathways, and interactive networks. The p-values were subjected to the false discovery rate for the correction of multiple tests. Thirty-nine syndromes were identified, and dental agenesis was the most frequent dental anomaly present in 41.02% (n = 16) of the syndromes. Causative genes were identified in 33 out of 39 genetic syndromes. Among them, 39 genes were identified, and 38 were analyzed by STRING, which showed 148 biological processes and three pathways that were statistically significant. The most significant biological processes were the disassembly of the nucleosome (GO:0006337, p = 1.09e-06), chromosomal organization (GO:0051276, p = 1.09e-06) and remodeling of the chromatin (GO: 0006338, p = 7.86e-06), and the pathways were hepatocellular carcinoma (hsa05225, p = 5.77e-05), thermogenesis (hsa04714, p = 0.00019), and cell cycle (hsa04110, p = 0.0433). Our results showed that the identification of hypertrichosis and dental anomalies may raise the suspicion of one of the thirty-nine syndromes with both phenotypes.

Clinics and genetic background of hereditary gingival fibromatosis

BACKGROUND

Hereditary gingival fibromatosis (HGF) is a rare condition characterized by slowly progressive overgrowth of the gingiva. The severity of overgrowth may differ from mild causing phonetic and masticatory issues, to severe resulting in diastemas or malposition of teeth. Both, autosomal-dominant and autosomal-recessive forms of HGF are described. The aim of this review is a clinical overview, as well as a summary and discussion of the involvement of candidate chromosomal regions, pathogenic variants of genes, and candidate genes in the pathogenesis of HGF. The loci related to non-syndromic HGF have been identified on chromosome 2 (GINGF, GINGF3), chromosome 5 (GINGF2), chromosome 11 (GINGF4), and 4 (GINGF5). Of these loci, pathogenic variants of the SOS-1 and REST genes inducing HGF have been identified in the GINGF and the GINGF5, respectively. Furthermore, among the top 10 clusters of genes ranked by enrichment score, ATP binding, and fibronectin encoding genes were proposed as related to HGF.

CONCLUSION

The analysis of clinical reports as well as translational genetic studies published since the late'90s indicate the clinical and genetic heterogeneity of non-syndromic HGF and point out the importance of genetic studies and bioinformatics of more numerous unrelated families to identify novel pathogenic variants potentially inducing HGF. This strategy will help to unravel the molecular  mechanisms as well as uncover specific targets for novel and less invasive therapies of this rare, orphan condition.

Syndromes with gingival fibromatosis: A systematic review

OBJECTIVE

The aim of systematic review was to describe the phenotypes and molecular profiles of syndromes with gingival fibromatosis (GF).

METHODS

A comprehensive search of PubMed, LILACS, Livivo, Scopus, and Web of Science was conducted using key terms relevant to the research questions and supplemented by a gray literature search. The Methodological Quality and Synthesis of Case Series and Case Reports in association with the Case Series and Prevalence Studies from the Joanna Briggs Institute critical appraisal tools were used for the risk of bias. We followed the PRISMA checklist guidelines.

RESULTS

Eighty-four studies reporting GF as an oral manifestation of a syndrome were identified in this review. Enamel renal syndrome was the most frequently reported syndrome with GF, represented by 54 individuals in 19 studies, followed by Zimmermann-Laband syndrome with 24 individuals in 15 studies and Costello syndrome, which was presented in a case series study with 41 individuals. Among reported cases, other clinical manifestations such as hypertrichosis, ectopic gingival calcification, and cherubism were described.

CONCLUSIONS

The results emphasize the need of systematic oro-dental-facial phenotyping for future descriptions as well as further molecular analysis in order to better understand the occurrence of syndromic GF.

Zimmermann-Laband syndrome: Clinical and cytogenetic study in two related patients

Background

Zimmermann–Laband Syndrome (ZLS) is an extremely rare autosomal dominant congenital disorder. It is a craniofacial malformation syndrome with predominant intraoral involvement consisting of gingival fibromatosis diffusion in early development. The molecular basis of ZLS is still unknown. Although familial aggregation with different inheritance patterns is detected in ZLS patients, most of the cases are sporadic.

Material and Methods

We report on two sibling patients with clinical manifestations of ZLS. Blood samples of both patients were obtained in EDTA-tubes followed by performing cytogenetic study using Cyto2.7M array. Analysis of the copy number was performed using the Chromosome Analysis Suite Software (version 1.0.1, annotation file na 30, Affymetrix) and interpreted with recourse to the UCSC genome browser (http://genome.ucsc.edu/; Human Mar. 2006NCBI Build 36.1/hg18 assembly).

Results

The array analysis revealed overlapping regions of chromosomal aberrations in both patients. We detected a 258-kb deletion at 3q13.13, a 89-kb duplication at 1q25.2 as well as two 67-kb duplications at 1p12 and 19q12. These altered regions do not contain any known genes and protein-coding sequences.

Conclusions

In conclusion, the findings of this report revealed new chromosomal aberrations, including a deletion at 3q13.13 and duplications at 1q25.2, 1p12 and 19q12, in the two patients with ZLS. Such findings indicate that whole genome screening for genomic rearrangements is fruitful in typical and atypical patients with ZLS.

Key words:Zimmermann-Laband syndrome, cytogenetic array, whole genome screening, chromosomal aberration, gingival fibromatosis.

Gingival fibromatosis: clinical, molecular and therapeutic issues

Gingival fibromatosis is a rare and heterogeneous group of disorders that develop as slowly progressive, local or diffuse enlargements within marginal and attached gingiva or interdental papilla. In severe cases, the excess tissue may cover the crowns of the teeth, thus causing functional, esthetic, and periodontal problems, such as bone loss and bleeding, due to the presence of pseudopockets and plaque accumulation. It affects both genders equally. Hereditary, drug-induced, and idiopathic gingival overgrowth have been reported. Hereditary gingival fibromatosis can occur as an isolated condition or as part of a genetic syndrome. The pathologic manifestation of gingival fibromatosis comprises excessive accumulation of extracellular matrix proteins, of which collagen type I is the most prominent example. Mutation in the Son-of-Sevenless-1 gene has been suggested as one possible etiological cause of isolated (non-syndromic) hereditary gingival fibromatosis, but mutations in other genes are also likely to be involved, given the heterogeneity of this condition. The most attractive concept of mechanism for drug-induced gingival overgrowth is epithelial-to-mesenchymal transition, a process in which interactions between gingival cells and the extracellular matrix are weakened as epithelial cells transdifferentiate into fibrogenic fibroblast-like cells. The diagnosis is mainly made on the basis of the patient's history and clinical features, and on histopathological evaluation of affected gingiva. Early diagnosis is important, mostly to exclude oral malignancy. Differential diagnosis comprises all pathologies in the mouth with excessive gingival overgrowth. Hereditary gingival fibromatosis may present as an autosomal-dominant or less commonly autosomal-recessive mode of inheritance. If a systemic disease or syndrome is suspected, the patient is directed to a geneticist for additional clinical examination and specialized diagnostic tests. Treatments vary according to the type of overgrowth and the extent of disease progression, thus, scaling of teeth is sufficient in mild cases, while in severe cases surgical intervention is required. Prognosis is precarious and the risk of recurrence exists.

Clinical and genetic study of two patients with Zimmermann-Laband syndrome and literature review

Zimmermann-Laband syndrome (ZLS) is a rare MCA/MR condition mainly characterized by gingival hypertrophy, hypo/aplastic nails and distal phalanges, hypertrichosis and intellectual disability. The molecular basis of ZLS is unknown. Most patients are sporadic, although familial aggregation is also observed with different inheritance patterns. We report on two unrelated children with full-blown characteristics of ZLS. Remarkable variability in expression included severity of neurocognitive involvement and extent of appendicular and facial features. In both, comparative genome hybridization array at a ~ 75 Mb resolution resulted negative, while aminoacid metabolic screening revealed high plasma levels of hypoxanthine and xanthine in one. Literature review identified 50 previously published patients (27 females, 23 males), including 14 familial, clustered in four pedigrees, and 37 sporadic. Tabulation of clinical features confirmed the core phenotype and identified developmental delay as the unique major clinical problem (occurring in 40% of the cases) with a moderately high risk of epilepsy (13%). Segregation analysis in the 20 sporadic patients with available data on healthy sibs and a single pedigree with affected sibs was significantly in contrast with an autosomal recessive mutation. An autosomal dominant mutation with high mutation rate and rare instances of germinal mosaicism seems the most likely inheritance pattern. This work may represent a starting point for future molecular studies aimed at identifying the molecular basis of ZLS.

Prenatal diagnosis of an autosomal translocation with regular trisomy 21

The coincidence of trisomy 21 and a structural rearrangement is very rare, and even it has not been reported as a prenatal diagnosis yet. In this article, we present an autosomal translocation carrier fetus with trisomy 21: 47,XX,+21, t(3;8)(p21;q24). Although the coincidence of reciprocal translocation and trisomy may be seen in reciprocal translocation carrier families, de novo cases are extremely rare. The presented case is diagnosed by amniocentesis, which was performed because of abnormal fetal ultrasonographic findings and increased trisomy 21 risk at maternal serum screening test. The postmortem pathologic examination of the fetus revealed that the findings of hypertelorism and right lung with two lobes are interesting novel findings of our cases associated with the breakpoints 3p21 and 8q24.

Expanding the phenotype of gingival fibromatosis-mental retardation-hypertrichosis (Zimmermann-Laband) syndrome

Zimmermann-Laband syndrome (ZLS) is a rare disorder characterized by gingival fibromatosis, hypertrichosis, intellectual disability, and absence and/or hypoplasia of the nails or terminal phalanges of the hands and feet. The syndromic features of ZLS are highly variable and can overlap with other entities featuring gingival fibrosis. This study describes a patient with ZLS with novel findings, including colpocephaly, hemivertebra, polydactyly, hyperpigmentation, and hemihyperplasia. Thus, the present report expands the phenotypic spectrum of this uncommon syndrome.

Case reports of a new syndrome associating gingival fibromatosis and dental abnormalities in a consanguineous family

BACKGROUND

Gingival fibromatosis (GF) is characterized by fibrotic enlargement of the gingiva that can be inherited as an isolated trait (named hereditary gingival fibromatosis) or as a component of a syndrome. This article reports one kindred affected by a syndrome characterized by GF associated with dental abnormalities (DA) including generalized thin hypoplastic amelogenesis imperfecta (AI).

METHODS

To characterize the pattern of inheritance and the clinical features, 70 family members were examined. Hematoxylin and eosin staining, immunohistochemistry, and scanning electronic microscopy (SEM) were performed to identify the alterations on gingiva, teeth, and dental follicles.

RESULTS

Examination of the family pedigree demonstrated multiple consanguineous first-cousin marriages and an autosomal recessive trait of inheritance. Four members demonstrated mild GF in association with DA, including generalized thin hypoplastic AI, intrapulpal calcifications, delay of tooth eruption, and pericoronal radiolucencies involving unerupted teeth. One of those four patients also had mental retardation (MR). MR as an isolated feature was observed in six members, whereas isolated GF was found in one individual. A combination of gingivectomy and gingivoplasty followed by regular dental procedures were performed in these patients. Histologic examination of the gingival enlargement revealed a dense connective tissue containing myofibroblasts, islands of odontogenic epithelium, and calcified psammomatous deposits, which resembled cementicle-like structures by SEM. Pericoronal lesions also showed calcified psammomatous deposits in association with islands of odontogenic epithelium. Enamel ultrastructure analysis revealed normal surface alternating with irregular and porous areas.

CONCLUSION

To the best of our knowledge, these cases represent a new syndrome within the spectrum of those including GF.

DOOR syndrome: clinical report, literature review and discussion of natural history

DOOR syndrome (deafness, onychodystrophy, osteodystrophy, and mental retardation) is a rarely described disorder with less than 35 reports in the literature. The hallmarks of the syndrome, represented in the DOOR acronym, include sensorineural hearing loss, hypoplastic or absent nails on the hands and feet, small or absent distal phalanges of the hands and feet, and mental retardation. The purpose of our communication is to report on an additional patient with DOOR syndrome, delineate common as well as less frequent manifestations of DOOR syndrome, bring attention to the under appreciated facial features in DOOR syndrome, document the natural history of this disorder, and propose a suggested workup of those suspected of DOOR syndrome. DOOR syndrome is associated with characteristic, coarse facial features with large nose with wide nasal bridge, bulbous tip and anteverted nares, a long prominent philtrum and downturned corners of the mouth. The natural history is one of a deteriorative course, with progressive neurological manifestations including sensorineural deafness, seizures from infancy, optic atrophy, and a peripheral polyneuropathy. The majority of patients with DOOR syndrome have elevated levels of 2-oxoglutarate in the urine and plasma. In this report, we present a newborn with manifestations consistent with DOOR syndrome and a progressive clinical course. A comprehensive literature review reveals 32 patients with DOOR syndrome. In conclusion, DOOR syndrome is a neurometabolic disorder with recognizable facial features and a progressive natural history.

Candidate loci for Zimmermann-Laband syndrome at 3p14.3

A male with 46,XY,t(3;17)(p14.3;q24.3) presented with gingival hyperplasia, hypertrichosis, unusually large ears and marked hypertrophy of the nose, characteristic of the Zimmermann-Laband syndrome (ZLS). Other features include large facial bones and mandibles, large protruding upper lip, enlarged fingers and toes, strabismus, and enlarged phallus. Knowledge of a 46,XX,t(3;8)(p21.2;q24.3) reported previously in a mother and daughter with ZLS suggests that the 3p14.3-p21.2 region may contain a gene responsible for ZLS. We have reassessed the chromosome 3 breakpoint region of the t(3;8) and revised its breakpoint location to 3p14.3, based upon an updated human genome sequence assembly. Using fluorescence in situ hybridization (FISH) with BAC clones, we have also identified a breakpoint spanning clone at 3p14.3 in our t(3;17) patient, thereby narrowing the breakpoint to a region of approximately 200 kb. These data suggest that the gene responsible for ZLS is located in 3p14.3 and implicates four likely candidate genes in this region: CACNA2D3, encoding a voltage-dependent calcium channel, LRTM1, a gene of unknown function embedded within CACNA2D3, WNT5A, encoding a secreted signaling protein of the WNT family, and ERC2, which codes for a synapse protein.

Ultrastructural investigation of Zimmermann-Laband syndrome

Zimmermann-Laband syndrome (ZLS) is a very rare autosomal dominant inherited condition characterized by 3 major clinical findings of which gingival hyperplasia are always present. The great heterogenicity of the syndrome is illustrated by the numerous variable clinical findings described in the literature. The purpose of the study was to examine a patient diagnosed with ZLS and to describe possible new characteristics of this rare syndrome, including the ultrastructural morphology using a transmission electron microscope (TEM) of the gingival and dermal fibroblasts. The ultrastrucutral morphology as has not previously been described in the literature. Tissue was collected from the alveolar ridge and skin of the forearm for TEM. TEM studies indicated the presence of prominent fibroblasts situated among numerous regular dense connective tissue bundles. Genetic analysis showed a new chromosomal insertion, ins(12;8)(p11.2;q11.2q24.3), suggesting that the gene responsible for the syndrome lies on chromosome 8.

[Syndromic gingival fibromatosis]

INTRODUCTION

Gingival fibromatosis is an inherited disease of the gingival tissue causing proliferative fibrous lesions occurring alone or as one feature of a more widespread syndrome.

OBSERVATION

A 26-year-old girl consulted the oral surgery department for a functional problem due to the presence of two tumor masses located in the palate. The histological diagnosis was gingival fibromatosis. The presence of skeletal disorders in this patient with gingival fibromatosis suggested the diagnosis of Zimmermann Laband syndrome.

DISCUSSION

Gingival fibromatosis is a rare condition characterized by a gingival hypertrophy. It is transmitted by autosomal dominant or recessive inheritance. The oral examination and histology provides the diagnosis. The treatment consistes of surgical removal of the hyperplasic fibrous tissue. Prognosis is dominated by the risk of recurrence which is frequent. Generally, gingival fibromatosis is isolated. In rare cases, it can be associated with symptoms sugges-ting a syndromic diagnosis such as Zimmermann Laband syndrome. In addition to gingival hypertrophy, skeletal anomalies can involve the fingers, the toenails, the thorax or the vertebrae. Splenomegaly and joint hyperextensibility can also be found.

The phenotypic overlap of syndromes associated with hereditary gingival fibromatosis: follow-up of a family for five years

Hereditary gingival fibromatosis (HGF) is characterized by the slowly progressive fibrous enlargement of gingival tissue. It usually develops as an isolated disorder but can also be one feature of various syndromes. The currently preferred terminology of these syndromes mainly describes the clinical features of the disorder without identifying the cause. In this report, we present the 5-year follow up of a family with HGF and features of 3 previously described syndromes: Jones syndrome, Zimmerman-Laband syndrome, and HGF-hypertrichosis syndrome. The 45-year-old father had HGF, hypertrichosis, hearing loss, and short stubby fingers and toes with hypoplasia of the terminal phalanges and hypoplasia of the nails on the thumbs. The features of 13-year-old son were almost identical to those of his father except for hypertrichosis, but in addition he was mentally retarded. Although the 10-day-old son had HGF and defective fingers, the mother and 7-year-old daughter were unaffected. Owing to the overlap of these syndromes, we argue that the identification of the genetic pathways and mechanisms will be the most important factor in classifying these disorders, with the phenotype playing a minor role.

Hereditary Gingival Fibromatosis: A Systematic Review

Generalized gingival enlargement can be caused by a variety of etiological factors. It can be inherited (hereditary gingival fibromatosis [HGF]); associated with other diseases characterizing a syndrome; or induced as a side effect of systemic drugs, such as phenytoin, cyclosporin, or nifedipine. HGF, previously known as elephantiasis gingivae, hereditary gingival hyperplasia, and hypertrophic gingiva, is a genetic disorder characterized by a progressive enlargement of the gingiva. This review will focus on diagnosis, treatment, and control of HGF. The pattern of inheritance, the histopathologic characteristics, and the known biologic and genetic features associated with HGF are also emphasized.

Zimmermann-Laband syndrome in an infant with an atypical histologic finding

Zimmermann-Laband syndrome is an inherited disorder that is characterized by abnormalities of the head, face, hands, and feet. Most children with this disorder have generalized hypertrichosis, large gingivae, and hypoplasia of the fingernails and toenails. We report a male infant who exhibited typical features of Zimmermann-Laband syndrome with an unusual histopathologic finding. Excised tissue from the infant's gingivae showed papillary projections that were composed of hyperplastic stratified squamous epithelium with different amounts of keratinization.