Molecular analysis of lipoid proteinosis: identification of a novel nonsense mutation in the ECM1 gene in a Pakistani family

Extracellular Matrix Protein 1 Gene Mutation in Turkish Patients with Lipoid Proteinosis

Background:

Lipoid proteinosis (LP) is a rare autosomal recessive genodermatosis characterized by mucocutaneous lesions and hoarseness of voice that develop in early childhood. LP is caused by mutation in the extracellular matrix protein 1 (ECM1) gene, which is located on 1q21.2.

Aims:

This study aimed to present the profile of ECM1 gene mutations and to identify possible novel mutations specific to Turkey.

Materials and Methods:

The ECM1 gene mutations of 19 LP patients from five families were evaluated using DNA isolated from peripheral blood samples. All ten exons in the ECM1 gene region were amplified by polymerase chain reaction (PCR). The PCR products were analyzed using a DNA sequencing analyzer. The results of DNA sequencing were analyzed with bioinformatics methods.

Results:

of the 19 LP patients evaluated in our study, we detected defects in exon 6 (c.507delT, 658T>G), exon 9 (157C>T, 727C>T), and exon 10 (c.93_94delGCinsTT) of the ECM1 gene.

Conclusions:

Our results indicate that defects in exons 6, 9, and 10 of the ECM1 gene were responsible for LP in our country. The identification of these pathogenic mutations is valuable because it facilitates early diagnosis and genetic counseling.

A novel nonsense mutation in exon 9 in the extracellular matrix protein 1 gene associated with lipoid proteinosis: A case report

Lipoid proteinosis is a rare autosomal recessive genodermatosis that is caused by loss-of-function mutations in the extracellular matrix protein 1 gene. This study identifies a novel nonsense mutation in exon 9 of the extracellular matrix protein 1 gene associated with lipoid proteinosis, contributing to recent advances in our understanding of the molecular genetics underlying this disease. It is important to identify the mutations in the extracellular matrix protein 1 gene that are associated with lipoid proteinosis and how these affect protein function. Understanding the molecular basis for such genetic disorders may lead to novel therapeutic approaches for treating hereditary genodermatoses.

Identification and association of recurrent ALOXE3 mutation with non-bullous congenital ichthyosiform erythroderma in two ethnically distinct Pakistani families

Non-bullous congenital ichthyosiform erythroderma (NCIE) is characterized by skin scaling with erythema. In this study, two Pakistani families with NCIE are genetically characterized through Whole Exome and Sanger sequencing to identify molecular basis of the disease. We identified a nonsense homozygous c.2026C>T mutation of ALOXE3, causing premature termination of the eLOX3 protein (p.Q676X). In silico studies predicted impaired enzymatic activity of the premature truncated eLOX3, leading to abnormal synthesis of specific hepoxilin derivatives, essential for epidermal barrier formation. It is the first ever study reporting homozygotes of p.Q676X mutation in ethnically distinct two Pakistani families; otherwise, heterozygotes of the said mutation have been reported in South Asian population only. Hence, mutation seems to be region-specific and may be useful for molecular diagnosis of NCIE. Moreover, our findings should help in genetic counseling and career screening.

Lipoid proteinosis: A clinical and molecular study in Egyptian patients

Lipoid proteinosis (LP) is an autosomal recessive disorder caused by the loss of function of ECM1 gene. Clinical features include varying degrees of skin thickening, hoarseness of voice and less frequently neuropsychiatric abnormalities. Twelve patients from ten unrelated families with a clinical diagnosis of lipoid proteinosis were enrolled in this study. Extraction of DNA samples of the 12 patients and their parents from peripheral blood by standard methods was performed. Polymerase chain reaction (PCR) amplification of the ECM1 gene was conducted using eight pairs of primers spanning over the 10 exons and splice junctions. Patients exhibited a variety of clinical manifestations with skin affection and hoarseness of voice being the consistent feature. We identified five novel homozygous insertion, small deletion, missense, and splice site mutations as well as two homozygous previously published splice site mutation c.70+1G>C in intron 1 and c.1305-2A>G in intron 8. The specific mutations were: c.10_11insC in exon 1, c.690_691delAG in exon 6, c.734G>A in exon 7, c.1286_1287delAA in exon 8 and c.1393-1G>T in intron 9. The novel mutations c.1393-1G>T and c.10_11insC occurred in three (30%) and two (20%) unrelated patients of the studied families, respectively. Further studies may designate an increased frequency of these mutations among Egyptian LP patients. Identification of pathogenic ECM1 mutations is important for accurate diagnosis and proper genetic counseling.

A Novel ECM1 Splice Site Mutation in Lipoid Proteinosis: Case Report plus Review of the Literature

Lipoid proteinosis (LP) is an autosomal recessive genodermatosis known to be caused by mutations in ECM1. Nonsense and missense mutations are the most common variations in LP. Up to date, only 6 splice site mutations have been observed. We report on a 26-year-old female LP patient from a Turkish consanguineous family carrying a novel homozygous splice site mutation in intron 8 of the ECM1 gene and summarize the current knowledge on ECM1 mutations and possible genotype-phenotype correlations.

Treatment of lipoid proteinosis with acitretin in two patients from two unrelated Chinese families with novel nonsense mutations of the ECM1 gene

Lipoid proteinosis is a rare recessive genetic disorder caused by loss-of-function mutations to chromosome 1 at 1q21, the extracellular matrix protein 1 (ECM1) gene. Two children with lipoid proteinosis were reported from two unrelated Chinese families, both manifesting with a typical hoarse voice, white acne-like atrophic lesions and scarring on the skin, and beaded papules around the eyelids. The diagnosis had been confirmed by laboratory tests, skin biopsy and laryngoscope examination. Genomic DNA sequencing was performed for both children and their family members. The two children were treated with acitretin for 6 months and followed up for 1 year. Genomic DNA sequencing of the ECM1 gene showed a novel homozygous nonsense mutation of C1522>T (p.R508X) at exon 10 in one patient, and a novel compound heterozygote for a nonsense/frame-shift combination of mutations of R281X/1596delG at exons 7 and 10 in the other patient. The symptom of hoarse voice was improved by 6-month treatment with acitretin, while there was no improvement in the skin lesions. These results demonstrated that acitretin treatment may have efficacy for some of patients with lipoid proteinosis, with superior effect on laryngeal symptoms than skin lesions. However, the conclusive therapeutic effect and underlying mechanisms remain to be further investigated.

Treatment of lipoid proteinosis due to the p.C220G mutation in ECM1, a major allele in Chinese patients

Background

Lipoid proteinosis (LP) is known to be resulted from mutations of the extracellular matrix protein 1 gene (ECM1). However, no effective or sustained therapeutic methods to alleviate LP symptoms have been reported.

Methods

Here, we report a 12-year-old boy with LP and recurrent anaphylaxis. The laboratory and histopathological investigations were adopted to confirm the diagnosis, and gene sequencing was performed. We treated this patient with glucocorticoid for three years to relieve the patient’s lipid metabolism disorder and symptoms related to LP and anaphylaxis.

Results

The Laboratory and histopathological investigations showed a lipid metabolism disorder and anaphylaxis in the patient. A homozygous missense mutation p.C220G of ECM1 was identified by Sanger sequencing, which is a major allele in Chinese patients with LP. Notably, after three years’ treatment, the symptoms such as skin lesions, stiff oral mucosa and hoarse voice in the patient were significantly relieved or recovered.

Conclusions

Our report may provide a potentially effective therapeutic approach for the first time to other LP patients who are experiencing recurrent anaphylaxis and/or chronic inflammation.

Identification of recurrent c.742G>T nonsense mutation in ECM1 in Pakistani families suffering from lipoid proteinosis

Lipoid proteinosis (LP) is one of the rare, recessive autosomal disorders clinically characterized by widespread deposition of hyaline-like material in the skin, mucosa and viscera. Classical features include beaded eyelid papules, laryngeal infiltration and hoarseness of voice caused by pathogenic mutations in the ECM1 gene located on 1q21.2. In present study ethnically different, three consanguineous Pakistani families with typical cutaneous features of LP were analysed to investigate the underlying molecular basis. PCR based linkage analysis using microsatellite markers localized the families to locus 1q21.2, harboring ECM1 gene. To identify the mutation in the candidate gene (ECM1), Sanger sequencing was carried out. All the families were found to carry c.742 G>T nonsense mutation in exon 7 of the ECM1 gene that resulted in a truncated ECM1 protein containing 247 amino acids instead of 540 (p.E248X). To further investigate the impact and importance of mutation in LP pathogenesis we applied different bioinformatics tools. In silico studies has predicted lack of functional domains and 65 % shorter ECM1 mutant protein. It is the first report of recurrence mutation from Pakistan as c.742G>T nonsense mutation was found in three ethnically different Pakistani families with LP. Study strengthens the conclusion that c.742G>T mutation is the pathological cause of LP. Furthermore, data also support the fact that exon 7 is one of the most common hot spots of pathological mutations in ECM1. The absence of functional domains and truncated sequence most likely contribute to the lack of ECM1 function and thereby influence several aspects of dermal homeostasis that leads to LP pathogenesis.

Melkerrson-Rosenthal Syndrome, a rare case report of chronic eyelid swelling

Abstract

Melkerrson-Rosenthal syndrome is a rare disorder of unknown etiology. The classical triad of recurrent facial paralysis, swelling of the face, lips and deep furrowed tongue (Lingua Plicata) is seen in very few cases, majority of the patients often present with one or two symptoms only, which often leads to misdiagnosis and mismanagement. Clinically these symptoms vary from days to years, which further delay the definitive diagnosis and symptoms may eventually become permanent. The cause of this entity is not very well understood, but thought to be attributable to multiple entities including genetic and Infectitious. As this entity has been associated with numerous other clinical entities, diagnosis often remains an exclusion process. Methods: A middle age male with a chronic history of heavy eyelids with skin indurations predominately around left eye was presented to ophthalmology clinic. Physical examination revealed a deep furrowed tongue. The skin biopsy from left eyelid revealed a non-specific granulomatous lesion. The clinical correlation of facial swelling and deep plicated tongue prompted the differential of MRS Results: Histologically a non-specific granulomatous lesion was seen in dermis. As a rule, other causes of granulomatous diseases were ruled out especially Crohn’s disease and sarcoidosis. Polarization failed to reveal any foreign body. Conclusions: The finding of granulomatous lesion and clinical picture led to the definite diagnosis of Melkerrson-Rosenthal syndrome. Association with rosacea was other findings. Clinically his sign and symptoms are under control and no occurrence of symptoms has been noted so far.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1647494495993706

A novel association of the additional intracranial calcification in lipoid proteinosis: a case report

Lipoid Proteinosis (LP) is a genetically linked, autosomally transferred, rare, chronic multisystem disease which is characterized by a normal lipid profile, but with abnormal deposits of lipids and proteins in the body, which slowly but steadily leads to systemic manifestations. Although it affects almost all the systems of the body, it predominantly manifests as lesions on the skin and it has characteristic intracranial calcifications. Although, the intracranial calcifications can be classified, based on their aetiopathogenesis, as agerelated and physiologic, congenital, infectious, endocrine and metabolic, vascular, and neoplastic; the symmetric calcifications in LP are a distinct entity. To one who is aware of this entity, LP is usually an incidental diagnosis. No permanent cure is available for LP till date. Only symptomatic medical treatment is being given. With the increasing awareness on this entity, LP can now be detected in its early phase and it can be better managed.As this condition is rare, it is necessary to spread awareness on this entity in the scientific community and hence this case is being reported. This case report is the first to demonstrate a novel association of an additional intracranial calcification in Lipoid Proteinosis.