[Focal dermal hypoplasia associated with pathogenic PORCN gene variant in postzygotic, unilateral mosaic form]

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.

REPRODUCTIVE OPHTHALMOLOGY: The Intersection of Inherited Eye Diseases and Reproductive Technologies

PURPOSE

To propose a working framework for patients with inherited eye diseases presenting to ophthalmologists who are interested in assisted reproductive technology and preimplantation genetic testing.

METHODS

Retrospective chart review and case series of three families with inherited eye diseases who successfully underwent preimplantation genetic testing, in vitro fertilization, and birth of unaffected children.

RESULTS

Preimplantation genetic testing was performed for three families with different inherited eye diseases, which included autosomal dominant retinitis pigmentosa, autosomal recessive achromatopsia, and X-linked Goltz syndrome. Preimplantation genetic testing led to the identification of unaffected embryos, which were then selected for in vitro fertilization and resulted in the birth of unaffected children.

CONCLUSION

A close collaboration between patients, families, ophthalmologists, reproductive genetic counselors, and reproductive endocrinology and infertility specialists is the ideal model for taking care of patients interested in preimplantation genetic testing for preventing the transmission of inherited eye diseases.

Porcn is essential for growth and invagination of the mammalian optic cup

Microphthalmia, anophthalmia, and coloboma (MAC) are congenital ocular malformations causing 25% of childhood blindness. The X-linked disorder Focal Dermal Hypoplasia (FDH) is frequently associated with MAC and results from mutations in Porcn, a membrane bound O-acyl transferase required for palmitoylation of Wnts to activate multiple Wnt-dependent pathways. Wnt/β-catenin signaling is suppressed in the anterior neural plate for initiation of eye formation and is subsequently required during differentiation of the retinal pigment epithelium (RPE). Non-canonical Wnts are critical for early eye formation in frog and zebrafish. However, it is unclear whether this also applies to mammals. We performed ubiquitous conditional inactivation of Porcn in mouse around the eye field stage. In Porcn CKO , optic vesicles (OV) arrest in growth and fail to form an optic cup. Ventral proliferation is significantly decreased in the mutant OV, with a concomitant increase in apoptotic cell death. While pan-ocular transcription factors such as PAX6, SIX3, LHX2, and PAX2 are present, indicative of maintenance of OV identity, regional expression of VSX2, MITF, OTX2, and NR2F2 is downregulated. Failure of RPE differentiation in Porcn CKO is consistent with downregulation of the Wnt/β-catenin effector LEF1, starting around 2.5 days after inactivation. This suggests that Porcn inactivation affects signaling later than a potential requirement for Wnts to promote eye field formation. Altogether, our data shows a novel requirement for Porcn in regulating growth and morphogenesis of the OV, likely by controlling proliferation and survival. In FDH patients with ocular manifestations, growth deficiency during early ocular morphogenesis may be the underlying cause for microphthalmia.

Neonatal Onset Glaucoma in a Case with Gorlin-Goltz Syndrome: An Unusual Association

Aim and objective

To report a unique presentation of Gorlin–Goltz syndrome (GGS) with congenital glaucoma.

Materials and methods

We report a case of a 3-month-old female patient with bilateral uncontrolled intraocular pressures (IOP), who was already diagnosed with GGS. Examination under anesthesia demonstrated microcornea, iris coloboma, lens subluxation in both eyes, and edematous cornea in the left eye. Intraocular pressure was 17 mm Hg in OD and 35 mm Hg in OS with Icare (Icare® PRO) tonometer on repetitive measurements. On dilated fundus examination, a large chorioretinal coloboma was seen on both eyes.

Results

On physical examination, cutaneous, dental, and skeletal anomalies associated with the GGS were found. As previously reported ocular abnormalities associated with the GGS; coloboma and microphthalmia were noted. In addition, congenital glaucoma which is not one of the known associations of GGS was also detected. For treatment, 270° transscleral diode cyclophotoablation was performed for the left eye and medical treatment was reorganized for both eyes.

Conclusion

Neonatal-onset glaucoma might be one of the important ocular manifestations of GGS.

How to cite this article

Tefon Arıbaş AB, Aktaş Z, Özdek Ş. Neonatal Onset Glaucoma in a Case with Gorlin–Goltz Syndrome: An Unusual Association. J Curr Glaucoma Pract 2021;15(2):99–101.

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.

Rare and unusual case of familial focal dermal hypoplasia (Goltz syndrome) presenting to otolaryngology in the UK

Goltz syndrome or focal dermal hypoplasia (FDH), is an X-linked dominant condition which predominantly involves the skin, limbs and eyes. In otolaryngology, FDH has been poorly described, but can result in increased symptoms of obstructive sleep apnoea requiring surgery. There have also been documented cases of mixed severe hearing loss secondary to congenital ossicular anomalies. More frequently, patients present to the ear-nose-throat clinic with symptoms of dysphagia, secondary to papillomatosis. A 36-year-old woman presented with pain, irritation and dysphagia with a known diagnosis of FDH. She was subsequently investigated with an oesophago-gastro-duodenoscopy, Barium Swallow and an MRI neck scan with contrast. Lymphoid hyperplasia was found on investigation and the patient underwent a panendoscopy with CO2 laser to the lesion with good clinical outcome. This case report highlights the need for multidisciplinary team involvement to ensure full consideration of management options.

Goltz-Gorlin Syndrome: Revisiting the Clinical Spectrum

OBJECTIVE

To describe the varying phenotypic spectrum of Focal Dermal Hypoplasia (FDH) and to emphasize the need for identifying the condition in mildly affected females which is crucial for offering a prenatal diagnosis in subsequent pregnancy owing to the risk of having a severely affected baby.

METHODS

The phenotype-genotype correlation of 4 patients with FDH, over a period of 11 y from the genetic clinic in a tertiary care centre from Kerala, India was done.

RESULTS

All four mutation proven patients were females (2 adults and 2 children). One of the adult female subjects were mildly affected, though she had a history of having a severely affected female child who expired on day six. Among the 2 affected children, one of them had an unaffected mother and the other had an affected mother.

CONCLUSIONS

FDH has a wide clinical spectrum from very subtle findings to severe manifestations. The lethality of the condition in males and the disfigurement and multisystem involvement in females highlights the importance of confirmation of diagnosis by molecular analysis so that the family can be offered prenatal diagnosis in subsequent pregnancy.

Goltz syndrome in males: A clinical report of a male patient carrying a novel PORCN variant and a review of the literature

Here, we report a novel mosaic mutation in the PORCN gene in a male Goltz syndrome patient. We also compare the phenotypes of all reported males with a confirmed molecular diagnosis. This report serves to further clarify the phenotype of Goltz syndrome and suggests that expression in males varies.