Dentofacial manifestations of a Paediatric patient with Goltz-Gorlin Syndrome.

Goltz-Gorlin syndrome is a rare X-linked inherited disorder associated with PORCN (porcupine homolog-Drosophila) gene mutation. It primarily affects the skin and its appendages. The characteristic cutaneous features include a blaschko-linear pattern, skin atrophy, pigmentary changes, and telangiectasia. The oral manifestations have been reported in more than half of the affected individuals. The most common oral findings include enamel hypoplasia, hypodontia, supernumerary teeth, microdontia, vertical grooving of the teeth, taurodontism, fusion, and abnormal root morphology reported in sporadic cases. The objective of this case report is to describe the dentofacial characteristics of a middle childhood aged girl with Goltz-Gorlin syndrome.

[Focal dermal hypoplasia associated with pathogenic PORCN gene variant in postzygotic, unilateral mosaic form]. / Fokale dermale Hypoplasie durch pathogene Variante im PORCN-Gen in postzygotischer, unilateraler Mosaik-Konstellation.

We report a case of a 29-year-old woman with subtle partial erythematous, partial hyperpigmented streaks along the Blaschko's lines on the right side of the body since early childhood. Primary DNA results of the skin and blood assay diagnosed focal dermal hypoplasia in mosaic form. The postzygotic mutation in the PORCN gene was only detectable in the affected skin and not in the blood assay. This article illustrates that clinically very discrete hypopigmentation and poikiloderma along Blaschko lines should raise awareness for robust diagnostic analysis in order to recognize this variable multisystem disease and to ensure an appropriate search for extracutaneous abnormalities and human genetic counseling, ideally before pregnancy. Careful correlation of clinical, histological, and genetic features along with close multidisciplinary cooperation of specialists from the fields of human genetics, dermatology, pediatrics, orthopedics and ophthalmology is crucial for final diagnosis, assessment of the prognosis and targeted genetic counseling of affected individuals.

Case Report: Papillary thyroid carcinoma in Goltz-Gorlin syndrome.

Goltz-Gorlin syndrome (GGS), also known as focal dermal hypoplasia, is a rare X-linked disorder caused by pathogenic variants in the PORCN gene and characterized by several abnormalities, including skin and limb defects, papillomas in multiple organs, ocular malformations, and mild facial dysmorphism. To date, only approximately 300 cases have been described in the literature. A 16-year-old female patient, born with multiple congenital dysmorphisms consistent with GGS and confirmed by genetic exam, was referred to our outpatient clinic for the workup of a thyroid nodule. A thyroid ultrasound showed a bilateral nodular disease with a 17-mm large hypoechoic nodule in the right lobe. Cytological exam of fine needle aspiration biopsy was suspicious for malignancy. Thus, she underwent total thyroidectomy plus lymphadenectomy of the right central compartment. A histological exam disclosed a papillary thyroid carcinoma (PTC) with lymph node micrometastases. Radioiodine (131-Iodine) therapy was performed. At 3- and 6-month follow-up, the patient did not present either ultrasound or laboratory PTC recurrence. To our knowledge, we report the first case of PTC in a patient with GGS. Since thyroid cancer is rare among children and adolescents, we hypothesize that the PORCN pathogenic variant could be responsible for tumor susceptibility. We also provide an overview of the clinical findings on GGS patients already reported and discuss the possible pathogenetic mechanism that may underlie this rare condition, including the role of PORCN in tumor susceptibility.

Focal Dermal Hypoplasia.

This case report describes facial atrophic papules with telangiectasias, streaked hypopigmented and hyperpigmented papules on the left side of the trunk and extremities, and soft yellow fat herniations.

Urogenital presentation of a male patient with focal dermal hypoplasia.

Focal dermal hypoplasia (FDH) is a rare X-linked dominant syndrome characterized by streaky cutaneous atrophy in a blaschkoid distribution, skeletal dysplasias, and ocular abnormalities. Here, we report hypospadias and chordee identified in a male patient with molecularly confirmed FDH. This report highlights a new clinical manifestation of male patients with FDH.

Progression and flaring of focal dermal hypoplasia during an acute illness.

Focal dermal hypoplasia (FDH), or Goltz syndrome, is a rare genodermatosis affecting tissues of mesodermal and ectodermal origin. The characteristic skin changes have been reported to symptomatically flare in response to certain triggers as well as to progress over time in some cases. We present the case of a 5-year-old girl with cutaneous flaring and progression of FDH in the setting of septic shock. This case adds to the growing body of literature on both flaring and progression of the cutaneous manifestations of FDH.

Focal Dermal Hypoplasia with Osteopathia Striata.

Background: Focal dermal hypoplasia is a genetic disease of multiple systems initially affecting the skin, skeleton, dental, eyes and face with developmental abnormalities and facial dysmorphism. Focal dermal hypoplasia is X-linked dominant disease affecting the ectoderm, mesoderm and endoderm. 95% feature de novo and 90% of these are females. Focal dermal hypoplasia is induced by a mutation in the PORCN gene. Objective: The aim of this article is to present a case of a one-year-old girl child with multi-hypopigmented reticulated atrophic macules and patches grouped in linear mode at the lines of blaschko, skeleton abnormalities, umbilical hernia, developmental delay, hypoplastic nails, syndactyly and lobster claw deformity. Case report: A one-year-old girl child presented to the dermatology clinic with asymptomatic lesions since childhood with no improvement, with multi- hypopigmented skin lesions on the trunk and extremities since birth as linear erosions that heal gradually during few days, leaving peripheral hypopigmentation with hyperpigmentation with anomalies of limbs and nails and delayed development. She was born by normal vaginal delivery and weighed 2.5 kg at birth. None of the family members had such features. She had dental enamel anomaly and partial anodontia in the lower jaw. Sparse hair and partial alopecia (scalp, eyebrows and eyelashes) were recorded. Conclusion: Focal dermal hypoplasia is a congenital skin disease with a unique clinical feature. Thorough examination of the extremities is indicated for early proper genetic counseling and therapy.

Novel insights into PORCN mutations, associated phenotypes and pathophysiological aspects.

BACKGROUND: Goltz syndrome (GS) is a X-linked disorder defined by defects of mesodermal- and ectodermal-derived structures and caused by PORCN mutations. Features include striated skin-pigmentation, ocular and skeletal malformations and supernumerary or hypoplastic nipples. Generally, GS is associated with in utero lethality in males and most of the reported male patients show mosaicism (only three non-mosaic surviving males have been described so far). Also, precise descriptions of neurological deficits in GS are rare and less severe phenotypes might not only be caused by mosaicism but also by less pathogenic mutations suggesting the need of a molecular genetics and functional work-up of these rare variants. RESULTS: We report two cases: one girl suffering from typical skin and skeletal abnormalities, developmental delay, microcephaly, thin corpus callosum, periventricular gliosis and drug-resistant epilepsy caused by a PORCN nonsense-mutation (c.283C > T, p.Arg95Ter). Presence of these combined neurological features indicates that CNS-vulnerability might be a guiding symptom in the diagnosis of GS patients. The other patient is a boy with a supernumerary nipple and skeletal anomalies but also, developmental delay, microcephaly, cerebral atrophy with delayed myelination and drug-resistant epilepsy as predominant features. Skin abnormalities were not observed. Genotyping revealed a novel PORCN missense-mutation (c.847G > C, p.Asp283His) absent in the Genome Aggregation Database (gnomAD) but also identified in his asymptomatic mother. Given that non-random X-chromosome inactivation was excluded in the mother, fibroblasts of the index had been analyzed for PORCN protein-abundance and -distribution, vulnerability against additional ER-stress burden as well as for protein secretion revealing changes. CONCLUSIONS: Our combined findings may suggest incomplete penetrance for the p.Asp283His variant and provide novel insights into the molecular etiology of GS by adding impaired ER-function and altered protein secretion to the list of pathophysiological processes resulting in the clinical manifestation of GS.

Novel uses of laser therapy in Goltz syndrome.

Goltz syndrome is an X-linked dominant, multisystem birth defect due to PORCN mutation. The skin findings follow Blaschko's lines and often show epidermal atrophy and herniation of subcutaneous fatty tissue. Regarding treatment, light sources can offer a good therapeutic option for some manifestations of this rare disease and improve the aesthetic appearance of the skin lesions. We report two new cases of Goltz syndrome in which the cutaneous findings remarkably improved with pulsed dye laser and carbon dioxide laser.

Two new patients with focal dermal hypoplasia: A novel PORCN variant and insights on the diagnostic considerations.

Mutations in the PORCN gene cause an X-linked dominant condition; focal dermal hypoplasia (FDH), characterized by atrophic skin, pigmented skin lesions in addition to several ocular and skeletal malformations. FDH is rare with around 275 cases reported so far from diverse ethnic groups. Herein, we provide a report of two new patients with FDH from Egypt. In addition to the typical clinical manifestations of the disease, infrequently reported clinical findings in the form of broad metaphysis, bilateral short broad femurs, and dermal sinus over the sacrum were seen in Patient 1 and partial fusion of labia majora, ventral hernia, and bladder extrophy were present in Patient 2. Two heterozygous protein-truncating PORCN mutations were identified in our patients, a known nonsense c.370C>T p.(Arg124Ter) and a novel frameshift c.375delG p.(Ala126HisfsTer3). Segregation analyses confirmed that the two mutations were "de novo" and not inherited from any of the parents. Our study expands the clinical and mutational spectrum of focal dermal hypoplasia and emphasizes the importance of investigating the different body systems and organs for the early management of patients.

Structural model of human PORCN illuminates disease-associated variants and drug-binding sites.

Wnt signaling is essential for normal development and is a therapeutic target in cancer. The enzyme PORCN, or porcupine, is a membrane-bound O-acyltransferase (MBOAT) that is required for the post-translational modification of all Wnts, adding an essential mono-unsaturated palmitoleic acid to a serine on the tip of Wnt hairpin 2. Inherited mutations in PORCN cause focal dermal hypoplasia, and therapeutic inhibition of PORCN slows the growth of Wnt-dependent cancers. Based on homology to mammalian MBOAT proteins, we developed and validated a structural model of human PORCN. The model accommodates palmitoleoyl-CoA and Wnt hairpin 2 in two tunnels in the conserved catalytic core, shedding light on the catalytic mechanism. The model predicts how previously uncharacterized human variants of uncertain significance can alter PORCN function. Drugs including ETC-159, IWP-L6 and LGK-974 dock in the PORCN catalytic site, providing insights into PORCN pharmacologic inhibition. This structural model enhances our mechanistic understanding of PORCN substrate recognition and catalysis, as well as the inhibition of its enzymatic activity, and can facilitate the development of improved inhibitors and the understanding of disease-relevant PORCN mutants. This article has an associated First Person interview with the joint first authors of the paper.

Non-syndromic anophthalmia/microphthalmia can be caused by a PORCN variant inherited in X-linked recessive manner.

Anophthalmia and microphthalmia (A/M) represent severe developmental ocular malformations, corresponding, respectively, to absent eyeball or reduced size of the eye. Both anophthalmia and microphthalmia may occur in isolation or as part of a syndrome. Genetic heterogeneity has been demonstrated, and many genes have been reported to be associated with A/M. The advances in high-throughput sequencing have proven highly effective in defining the molecular basis of A/M. Nevertheless, there are still many patients with unsolved genetic background of the disease, who pose a significant challenge in the molecular diagnostics of A/M. Here we describe a family, with three males affected with the non-syndromic A/M. Whole exome-sequencing performed in Patient 1, revealed the presence of a novel probably pathogenic variant c.734A>G, (p.[Tyr245Cys]) in the PORCN gene. Pedigree analysis and segregation of the identified variant in the family confirmed the X-linked recessive pattern of inheritance. This is the first report of X-linked recessive non-syndromic A/M. Until now, pathogenic variants in the PORCN gene have been identified in the patients with Goltz syndrome, but they were inherited in X-linked dominant mode. The ocular phenotype is the only finding observed in the patients, which allows to exclude the diagnosis of Goltz syndrome.