Spectrum of novel ATP2A2 mutations in patients with Darier's disease

Persistent Cutaneous Lesions of Darier Disease and Second-Hit Somatic Variants in ATP2A2 Gene

Importance

Darier disease (DD) is a rare genetic skin disorder caused by heterozygous variants in the ATP2A2 gene. Clinical manifestations include recurrent hyperkeratotic papules and plaques that occur mainly in seborrheic areas. Although some of the lesions wax and wane in response to environmental factors, others are severe and respond poorly to therapy.

Objective

To investigate the molecular mechanism underlying the persistency of skin lesions in DD.

Design, Setting, and Participants

In this case series, DNA was extracted from unaffected skin, transient and persistent lesional skin, and blood from 9 patients with DD. Genetic analysis was used using paired-whole exome sequencing of affected skin and blood or by deep sequencing of ATP2A2 of affected skin. Chromosomal microarray analysis was used to reveal copy number variants and loss of heterozygosity. All variants were validated by Sanger sequencing or restriction fragment length polymorphism.

Interventions or Exposures

Paired whole-exome sequencing and deep sequencing of ATP2A2 gene from blood and skin samples isolated from persistent, transient lesions and unaffected skin in patients with DD.

Main Outcomes and Measures

Germline and somatic genomic characteristics of persistent and transient cutaneous lesions in DD.

Results

Of 9 patients with DD, all had heterozygous pathogenic germline variants in the ATP2A2 gene, 6 were female. Participant age ranged from 40 to 69 years on enrollment. All 11 persistent skin lesions were associated with second-hit somatic variants in the ATP2A2 gene. The somatic variants were classified as highly deleterious via combined annotation-dependent depletion (CADD) scores or affect splicing, and 3 of them had been previously described in patients with DD and acrokeratosis verruciformis of Hopf. Second-hit variants in the ATP2A2 gene were not identified in the transient lesions (n = 2) or the normal skin (n = 2).

Conclusions and Relevance

In this study, persistent DD lesions were associated with the presence of second-hit somatic variants in the ATP2A2 gene. Identification of these second-hit variants offers valuable insight into the underlying mechanisms that contribute to the lasting nature of persistent DD lesions.

MicroRNA-200c-3p Negatively Regulates ATP2A2 and Promotes the Progression of Papillary Thyroid Carcinoma

microRNA-200c-3p (miR-200c-3p) has emerged as an important tumor growth regulator. However, its function in papillary thyroid carcinoma (PTC) is poorly understood. This study was conducted to investigate the role of miR-200c-3p in the progression of human PTC. The miR-200c-3p expression in human PTC tissues and cell lines was evaluated. The target relationship between miR-200c-3p and candidate genes was predicted through bioinformatic analysis and confirmed with a luciferase reporter assay. miRNA or gene expression was altered using transfection, and cell behavior was analyzed using CCK-8, wound healing, Transwell, and colony formation assays. The tumor-promoting effects of miR-200c-3p were evaluated by xenografting tumors with K1 cells in nude mice. The expression level of miR-200c-3p in human PTC tissues and cell lines markedly increased, and this increased expression was significantly associated with a worse overall survival. When inactivated, miR-200c-3p suppressed K1 cells’ malignant behaviors, including decreasing proliferation and attenuating colony formation, migration, and invasion. Its inactivation also attenuated the development of xenografted K1 cells in nude mice. The effects of miR-200c-3p mimics on promoting the malignant behaviors of PTC cells were remarkably reversed by the overexpression of ATP2A2, as a downstream target of miR-200c-3p. miR-200c-3p acts as an oncogenic gene and promotes the malignant biological behaviors of human PTC cells, thereby directly targeting ATP2A2. This regulated axis may be used as a potential therapy of PTC.

Brain-specific heterozygous loss-of-function of ATP2A2, endoplasmic reticulum Ca2+ pump responsible for Darier's disease, causes behavioral abnormalities and a hyper-dopaminergic state

A report of a family of Darier's disease with mood disorders drew attention when the causative gene was identified as ATP2A2 (or SERCA2), which encodes a Ca2+ pump on the endoplasmic reticulum (ER) membrane and is important for intracellular Ca2+ signaling. Recently, it was found that loss-of-function mutations of ATP2A2 confer a risk of neuropsychiatric disorders including depression, bipolar disorder and schizophrenia. In addition, a genome-wide association study found an association between ATP2A2 and schizophrenia. However, the mechanism of how ATP2A2 contributes to vulnerability to these mental disorders is unknown. Here, we analyzed Atp2a2 heterozygous brain-specific conditional knockout (hetero cKO) mice. The ER membranes prepared from the hetero cKO mouse brain showed decreased Ca2+ uptake activity. In Atp2a2 heterozygous neurons, decays of cytosolic Ca2+ level were slower than control neurons after depolarization. The hetero cKO mice showed altered behavioral responses to novel environments and impairments in fear memory, suggestive of enhanced dopamine signaling. In vivo dialysis demonstrated that extracellular dopamine levels in the NAc were indeed higher in the hetero cKO mice. These results altogether indicate that the haploinsufficiency of Atp2a2 in the brain causes prolonged cytosolic Ca2+ transients, which possibly results in enhanced dopamine signaling, a common feature of mood disorders and schizophrenia. These findings elucidate how ATP2A2 mutations causing a dermatological disease may exert their pleiotropic effects on the brain and confer a risk for mental disorders.

Role of induced pluripotent stem cells in diagnostic cardiology

Ethical concerns about stem cell-based research have delayed important advances in many areas of medicine, including cardiology. The introduction of induced pluripotent stem cells (iPSCs) has supplanted the need to use human stem cells for most purposes, thus eliminating all ethical controversies. Since then, many new avenues have been opened in cardiology research, not only in approaches to tissue replacement but also in the design and testing of antiarrhythmic drugs. This methodology has advanced to the point where induced human cardiomyocyte cell lines can now also be obtained from commercial sources or tissue banks. Initial studies with readily available iPSCs have generally confirmed that their behavioral characteristics accurately predict the behavior of beating cardiomyocytes in vivo. As a result, iPSCs can provide new ways to study arrhythmias and heart disease in general, accelerating the development of new, more effective antiarrhythmic drugs, clinical diagnoses, and personalized medical care. The focus on producing cardiomyocytes that can be used to replace damaged heart tissue has somewhat diverted interest in a host of other applications. This manuscript is intended to provide non-specialists with a brief introduction and overview of the research carried out in the field of heart rhythm disorders.

An Update on the Cutaneous Manifestations of Darier Disease

BACKGROUND

Knowledge about the clinical features of Darier disease, an orphan autosomal-dominant genetic disorder, is sparse and has been evaluated only in few studies.

OBJECTIVES

To investigate the clinical features of a large group of patients with Darier disease, and to explore for associations between disease characteristics and severity of the disease.

METHODS

Seventy-six individuals with Darier disease were evaluated utilizing a structured questionnaire-based interview, a physical examination, and a retrospective assessment of their medical records.

RESULTS

The most frequent locations of lesions were hands (99%) and fingernails (93%). Wart-like lesions on the hands were more visible after soaking them in water for 5 minutes, we therefore named this phenomenon the "wet hand sign". Oral involvement was found in 43% of patients, while 48% of women and 16% of men showed genital lesions. Patients with severe Darier disease had a tenfold greater risk of developing genital lesions than those with mild disease (P = .01). Most patients (88%) in our study exhibited a combination of the four types of the disease patterns of distribution (flexural, seborrheic, nevoid, and acral).

CONCLUSIONS

Documentation of disease on the hands and fingernails provides a highly sensitive means to aid in the diagnosis of Darier disease. It is important to evaluate mucosal lesions including genital and oral mucosa.

ATP2A2 SINE Insertion in an Irish Terrier with Darier Disease and Associated Infundibular Cyst Formation

A 4-month-old female Irish Terrier presented with a well demarcated ulcerative and crusting lesion in the right ear canal. Histological analysis revealed epidermal hyperplasia with severe acantholysis affecting all suprabasal layers of the epidermis, which prompted a presumptive diagnosis of canine Darier disease. The lesion was successfully treated by repeated laser ablation of the affected epidermis. Over the course of three years, the dog additionally developed three dermal nodules of up to 4 cm in diameter that were excised and healed without complications. Histology of the excised tissue revealed multiple infundibular cysts extending from the upper dermis to the subcutis. The cysts were lined by squamous epithelium, which presented with abundant acantholysis of suprabasal keratinocytes. Infundibular cysts represent a novel finding not previously reported in Darier patients. Whole genome sequencing of the affected dog was performed, and the functional candidate genes for Darier disease (ATP2A2) and Hailey-Hailey disease (ATP2C1) were investigated. The analysis revealed a heterozygous SINE insertion into the ATP2A2 gene, at the end of intron 14, close to the boundary of exon 15. Analysis of the ATP2A2 mRNA from skin of the affected dog demonstrated a splicing defect and marked allelic imbalance, suggesting nonsense-mediated decay of the resulting aberrant transcripts. As Darier disease in humans is caused by haploinsufficiency of ATP2A2, our genetic findings are in agreement with the clinical and histopathological data and support the diagnosis of canine Darier disease.

Structures of the heart specific SERCA2a Ca2+-ATPase

The sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase 2a (SERCA2a) performs active reuptake of cytoplasmic Ca²⁺ and is a major regulator of cardiac muscle contractility. Dysfunction or dysregulation of SERCA2a is associated with heart failure, while restoring its function is considered as a therapeutic strategy to restore cardiac performance. However, its structure has not yet been determined. Based on native, active protein purified from pig ventricular muscle, we present the first crystal structures of SERCA2a, determined in the CPA-stabilized E2-AlF4- form (3.3 Å) and the Ca²⁺-occluded [Ca₂]E1-AMPPCP form (4.0 Å). The structures are similar to the skeletal muscle isoform SERCA1a pointing to a conserved mechanism. We seek to explain the kinetic differences between SERCA1a and SERCA2a. We find that several isoform-specific residues are acceptor sites for post-translational modifications. In addition, molecular dynamics simulations predict that isoform-specific residues support distinct intramolecular interactions in SERCA2a and SERCA1a. Our experimental observations further indicate that isoform-specific intramolecular interactions are functionally relevant, and may explain the kinetic differences between SERCA2a and SERCA1a.

Altered levels of focal adhesion and extracellular matrix-receptor interacting proteins were identified in Hailey-Hailey disease by quantitative iTRAQ proteome analysis

Benign chronic familial pemphigus or Hailey-Hailey disease (HHD, OMIM 169600) is a rare, autosomal dominant blistering skin disorder characterized by suprabasal cell separation (acantholysis) of the epidermis. To date, the proteomic changes in skin lesions from HHD patients has not been reported yet. In this study, a sample of skin lesions from HHD patients was collected for isobaric tags for relative and absolute quantitation to analyze proteome changes compared with unaffected individuals. The 134 differentially expressed proteins were assigned to at least one Gene Ontology term, and 123 annotated proteins with significant matches were assigned to 187 known metabolic or signaling pathways listed in the Kyoto Encyclopedia of Genes and Genomes. Most of the altered proteins in skin lesions of HHD patients were enriched in pathways involved in the PI3K-Akt signaling, focal adhesion, extracellular matrix (ECM)-receptor interaction, and protein digestion and absorption, such as collagen family members, microfibril-associated glycoprotein 4 and plakophilin. The changes of proteins related to cell adhesion, ECM-receptor interaction, and protein folding and glycosylation suggested that strategy targeted to alter cell junction and extracellular microenvironment might provide a potential treatment for HHD.

Genotype-phenotype correlations in Darier disease: A focus on the neuropsychiatric phenotype

Darier disease (DD) is an autosomal dominant skin disorder caused by mutations in ATP2A2 encoding the sarco/endoplasmic reticulum Ca²⁺ ATPase Isoform 2 (SERCA2). Evidence of a population-level association between DD and psychiatric disorders suggests that mutations in ATP2A2 may have pleiotropic effects on the brain as well as skin. Evidence of genotype-phenotype relationships between ATP2A2 mutations and neuropsychiatric phenotypes would further support this suggestion. We investigated genotype-phenotype correlations between lifetime neuropsychiatric features and ATP2A2 mutation type (dichotomized into likely gene disrupting [LGD] or protein altering) in 75 unrelated individuals with DD. We also looked for evidence of clustering of mutations within SERCA2 according to neuropsychiatric features. Combining our data with the existing literature, the rate of LGD mutations was found to be significantly higher among DD cases/families with bipolar disorder, schizophrenia, or affective psychosis (p = .011). We also found a significant relationship between mutations located in the S4-M4 region of the protein and the presence of a severe neuropsychiatric phenotype (p = .032). Our findings add support to the hypothesis that Darier-causing mutations in ATP2A2 confer susceptibility to neuropsychiatric dysfunction, in particular severe psychiatric illness. This, together with evidence from research on common polymorphisms confirms ATP2A2 as a gene at which variation influences susceptibility to major psychiatric illness.

Novel mutations in Darier disease and association to self-reported disease severity

Darier disease is a rare and severe autosomal dominant skin disease characterised by malodorous keratotic papules in seborrheic areas of the skin. Darier disease affects up to 1 in 30 000 people and is caused by mutations in the ATP2A2 gene, which encodes to the sarco/endoplasmic reticulum calcium-ATPase isoform 2 that pumps calcium into the endoplasmic reticulum. Although many ATP2A2 variants have been described, it is not known if genotype correlates with phenotype, which could be important for prognosis and treatment. This is the first study to use whole exome sequencing to screen the ATP2A2 gene in a cohort of 28 clinically diagnosed Darier disease patients. Twenty-one different disease causing variants were identified and 15 of these were novel. Sixteen of the 21 variants were predicted to be pathogenic using in silico prediction programs. There were seven missense, four intronic/splice-sites, three frameshifts, two in-frame deletions, four nonsense and one synonymous mutations. This study also found ten patients who harbour more than one ATP2A2 variant. The phenotype of the patient cohort was assessed by photography and by patient questionnaires. The genotype-phenotype association was examined for all variants in relation to the patient's disease severity score, and no correlation could be established.

Comprehensive Analysis of Tissue-wide Gene Expression and Phenotype Data Reveals Tissues Affected in Rare Genetic Disorders

Linking putatively pathogenic variants to the tissues they affect is necessary for determining the correct diagnostic workup and therapeutic regime in undiagnosed patients. Here, we explored how gene expression across healthy tissues can be used to infer this link. We integrated 6,665 tissue-wide transcriptomes with genetic disorder knowledge bases covering 3,397 diseases. Receiver-operating characteristics (ROC) analysis using expression levels in each tissue and across tissues indicated significant but modest associations between elevated expression and phenotype for most tissues (maximum area under ROC curve = 0.69). At extreme elevation, associations were marked. Upregulation of disease genes in affected tissues was pronounced for genes associated with autosomal dominant over recessive disorders. Pathways enriched for genes expressed and associated with phenotypes highlighted tissue functionality, including lipid metabolism in spleen and DNA repair in adipose tissue. These results suggest features useful for evaluating the likelihood of particular tissue manifestations in genetic disorders. The web address of an interactive platform integrating these data is provided.

Brief Report: HPV-17 Infection in Darier Disease With Acrokeratosis Verrucosis of Hopf

The co-existence of Darier disease (DD) and acrokeratosis verruciformis of Hopf (AKV) has been noted for decades and the relationship between the 2 entities remains controversial. Although, it has been shown that both diseases are associated with mutations in ATPA2 gene, it is yet to be determined if they are the same disease, or separate but allelic, or interlinked in some other fashion. Herein, the authors report the case of a 13-year-old girl presenting with shiny flat-topped verruca plana-like papules, on the dorsal hands and feet and red-brown crusted papules on her forehead and along the sides of her neck. Histological evaluation of a wart-like lesion shows features of AKV, a verruca plana-like histopathology and focal acantholytic dyskeratosis. Forehead biopsy also demonstrated focal acantholytic dyskeratosis supporting the diagnosis of DD. Polymerase chain reaction for human papillomavirus (HPV) DNA detected HPV-17, a human betapapillomavirus in the verruca plana-like papule. Cytoplasmic expression of the L1 capsid expression was seen in areas of hypergranulosis. The presence of productive betaPV infection in the setting of DD and AKV suggests a susceptibility to HPV infection.

Mendelian Disorders of Cornification Caused by Defects in Intracellular Calcium Pumps: Mutation Update and Database for Variants in ATP2A2 and ATP2C1 Associated with Darier Disease and Hailey-Hailey Disease

The two disorders of cornification associated with mutations in genes coding for intracellular calcium pumps are Darier disease (DD) and Hailey-Hailey disease (HHD). DD is caused by mutations in the ATP2A2 gene, whereas the ATP2C1 gene is associated with HHD. Both are inherited as autosomal-dominant traits. DD is mainly defined by warty papules in seborrheic and flexural areas, whereas the major symptoms of HHD are vesicles and erosions in flexural skin. Both phenotypes are highly variable. In 12%-40% of DD patients and 12%-55% of HHD patients, no mutations in ATP2A2 or ATP2C1 are found. We provide a comprehensive review of clinical variability in DD and HHD and a review of all reported mutations in ATP2A2 and ATP2C1. Having the entire spectrum of ATP2A2 and ATP2C1 variants allows us to address the question of a genotype-phenotype correlation, which has not been settled unequivocally in DD and HHD. We created a database for all mutations in ATP2A2 and ATP2C1 using the Leiden Open Variation Database (LOVD v3.0), for variants reported in the literature and future inclusions. This data may be of use as a reference tool in further research on treatment of DD and HHD.

Multiple Oral Mucosal Hamartomas in a 34-Year Old Female

A case of Cowden syndrome (CS) is described in a 34-year-old African American female who reported a history of breast and thyroid malignancies. Clinical examination demonstrated multiple soft, white-pink papules across multiple mucosal surfaces of the oral cavity. Microscopy of the lesions revealed hyperkeratotic surface squamous epithelium with papillomatosis and acanthosis along with elongated rete processes. A genomic polymerase chain reaction direct sequencing using the patient's blood was positive for mutations of the PTEN gene typical of CS.

Loss of function mutations in ATP2A2 and psychoses: A case report and literature survey

AIM

Though genetic factors play a major role in the pathophysiology of psychoses including bipolar disorder (BD) and schizophrenia, lack of well-established causative genetic mutations hampers their neurobiological studies. Darier's disease, an autosomal dominant skin disorder caused by mutations of ATP2A2 on chromosome 12q23-24.1, encoding sarco/endoplasmic reticulum calcium transporting ATPase 2 (SERCA2), reportedly cosegregates with BD. A recent genome-wide association study showed an association of schizophrenia with ATP2A2.

METHODS

We sequenced all coding regions of ATP2A2 in a newly identified patient with Darier's disease and BD. In addition, we performed a literature survey to examine whether likely gene disrupting (LGD) mutations are related to psychoses.

RESULTS

We identified a rare heterozygous mutation, c.1288-6A>G, at the 3' end of intron 10 in the patient. A minigene splicing assay showed that this mutation introduces a new splice site causing a frameshift and premature stop codon. A literature survey of case reports of patients with Darier's disease and psychoses revealed that the rate of LGD mutations causing frameshift, altered splicing, gain of stop codon, or loss of start codon was significantly higher among the mutations harbored by these cases (9 of 11) than that of ATP2A2 mutations for which comorbidity of psychosis was not reported (107 of 237, P = 0.026). The only non-LGD mutation (p.C560R) reported in patients with Darier's disease and BD caused decreased ATP2A2 protein expression.

CONCLUSION

These results suggest that psychoses in Darier's disease may be caused by a pleiotropic effect of loss-of-function mutations of ATP2A2.

Glycogen Fuels Survival During Hyposmotic-Anoxic Stress in Caenorhabditis elegans

Oxygen is an absolute requirement for multicellular life. Animals that are deprived of oxygen for sufficient periods of time eventually become injured and die. This is largely due to the fact that, without oxygen, animals are unable to generate sufficient quantities of energy. In human diseases triggered by oxygen deprivation, such as heart attack and stroke, hyposmotic stress and cell swelling (edema) arise in affected tissues as a direct result of energetic failure. Edema independently enhances tissue injury in these diseases by incompletely understood mechanisms, resulting in poor clinical outcomes. Here, we present investigations into the effects of osmotic stress during complete oxygen deprivation (anoxia) in the genetically tractable nematode Caenorhabditis elegans. Our findings demonstrate that nematode survival of a hyposmotic environment during anoxia (hyposmotic anoxia) depends on the nematode’s ability to engage in glycogen metabolism. We also present results of a genome-wide screen for genes affecting glycogen content and localization in the nematode, showing that nematode survival of hyposmotic anoxia depends on a large number of these genes. Finally, we show that an inability to engage in glycogen synthesis results in suppression of the enhanced survival phenotype observed in daf-2 insulin-like pathway mutants, suggesting that alterations in glycogen metabolism may serve as a basis for these mutants’ resistance to hyposmotic anoxia.

Intellectual disability and cognitive ability in Darier disease: Swedish nation-wide study

BACKGROUND

Darier disease is an autosomal dominant skin disorder caused by mutations in the ATP2A2 gene. Anecdotal reports suggest a relationship between Darier disease and intellectual disabilities, but these reports are based on small clinical samples and limited by absence of control populations.

OBJECTIVES

To examine the risk of intellectual disability and subclinical impairments in cognitive ability in Darier disease.

METHODS

We conducted a matched cohort study based on Swedish Population-, Patient- and Conscript Registers. The risk of being diagnosed with intellectual disability was estimated in 770 individuals with Darier disease, compared with matched comparison individuals without Darier disease. Associations were examined with risk ratios from conditional logistic regressions. In addition, we analysed test-based cognitive ability data (i.e. IQ data) from the Swedish conscript examination, for a subset of patients without diagnosed intellectual disability.

RESULTS

Individuals with Darier disease had a sixfold increased risk of being diagnosed with intellectual disability (risk ratio 6.2, 95% confidence interval 3.1-12.4). For conscripted individuals with Darier disease but no diagnosed intellectual disability, mean cognitive ability scores were about half a standard deviation lower than for comparison subjects.

CONCLUSIONS

Darier disease is associated with intellectual disability and subclinical impairments in cognitive ability. The Darier-causing mutations merit further attention in molecular genetic research on intellectual disability and cognitive ability.

The association between Darier disease, bipolar disorder, and schizophrenia revisited: a population-based family study

OBJECTIVES

Darier disease is an autosomal dominant skin disorder caused by mutations in the ATPase, Ca++ transporting, cardiac muscle, slow twitch 2 (ATP2A2) gene and previously reported to cosegregate with bipolar disorder and schizophrenia in occasional pedigrees. It is, however, unknown whether these associations exist also in the general population, and the objective of this study was to examine this question.

METHODS

We compared a national sample of individuals with Darier disease and their first-degree relatives with matched unexposed individuals from the general population and their first-degree relatives, respectively. To examine risks for bipolar disorder and schizophrenia, risk ratios and 95% confidence intervals (CIs) were estimated using conditional logistic regressions.

RESULTS

Individuals with Darier disease had a 4.3 times higher risk of being diagnosed with bipolar disorder (95% CI: 2.6-7.3) and a 2.3 times higher risk of being diagnosed with schizophrenia (95% CI: 1.1-5.2) than matched individuals from the general population. Relatives of individuals with Darier disease had a 1.6 times higher risk of having bipolar disorder (95% CI: 1.1-2.5) than relatives of matched individuals from the general population, but no increased risk of schizophrenia (risk ratio = 0.8, 95% CI: 0.4-1.8).

CONCLUSIONS

The association between Darier disease and bipolar disorder is manifest also in the population, and our data suggest that genetic variability within the ATP2A2 gene that causes Darier disease also confers susceptibility for bipolar disorder. The Darier-causing mutations merit additional attention in molecular genetic research on bipolar disorder.

Identification of two novel Darier disease‑associated mutations in the ATP2A2 gene

Darier disease (DD) is an autosomal dominant inherited skin disorder, characterized by abnormal keratinization, loss of adhesion between epidermal cells, termed acantholysis, and the development of warty papules and plaques on the central trunk, forehead, scalp and flexures. These symptoms are often exacerbated by heat, sweating, sunburn and stress. Mutations in the ATP2A2 gene, encoding SERCA2, a calcium pump of the sarco/endoplasmic reticulum, are responsible for the disease. The aim of the present study was to investigate two pedigrees of DD and to examine the genetic mutations. DNA was extracted from peripheral blood, which was obtained from four patients with DD, 10 healthy individuals from the two families and 100 ethnicity-matched control individuals, on which subsequent polymerase chain reaction amplification and direct automated DNA sequencing were performed. The results identified two novel missense mutations, p.R603I and p.G749 V. These mutations were not identified in the remaining ten healthy individuals in the same families or in any of the 100 controls. These mutations may contribute to the expanding database of ATP2A2 gene mutations in patients with DD.

Two novel missense mutations of ATP2A2 in two Chinese patients with sporadic Darier disease

Darier disease (DD) is a rare autosomal dominant skin disorder with characteristic abnormal keratinization and acantholysis. The causative gene, ATP2A2, is located on chromosome 12, and encodes a sarco/endoplasmic reticulum calcium pump ATPase (SERCA2). Two Chinese patients with sporadic DD participated in this study. Genomic sequence analysis identified two novel missense mutations (c.742C>A and c.2098A>G) in the ATP2A2 gene. Our findings provide an additional ATP2A2 mutation causative for DD development, and new lines of evidences for the understanding of genotype-phenotype correlations.

Cooccurrence of Darier's Disease and Epilepsy: A Pediatric Case Report and Review of the Literature

Darier's disease is a skin disorder characterized by multiple eruptions of hyperkeratosis or crusted papules at seborrheic areas with histologic acantholysis and dyskeratosis. It is caused by mutations in a single gene, being ATP2A2 and that is expressed in the skin and brain. The cooccurrence of various neurologic and psychiatric diseases with Darier's disease has been reported frequently in literature. They include mood disorders, epilepsy, encephalopathy, and schizophrenia. In this study, we report a pediatric case with the cooccurrence of Darier's disease and epilepsy. We also revised current English literature on this topic.

A case of zosteriform Darier's disease with seasonal recurrence

Darier's disease is an uncommon genodermatosis characterized by keratotic papules in seborrheic distribution. The disease can rarely present in unilateral zosteriform pattern, as a mosaic form following the Blaschko's line. We present a 35-year-old woman with zosteriform pattern of Darier's disease over right infra mammary region. The lesions occurred strictly during summers. Histologically, suprabasal acantholysis with abundant dyskeratotic cells were seen.

Acrokeratosis verruciformis of Hopf showing P602L mutation in ATP2A2 and overlapping histopathological features with Darier disease

The relationship between acrokeratosis verruciformis (AKV) of Hopf and Darier disease (DD) has been debated for several decades. Both diseases are now thought to result from mutations in the same gene, that is, the ATP2A2 gene encoding the sarco (endo) plasmic reticulum Ca ATPase2 pump (SERCA2), although their histopathological features are different. We sought to detect possible overlapping histopathological features between AKV and DD. Fourteen members of a family affected by AKV were analyzed for the underlying molecular genetic derangement, and 3 cases were studied histopathologically using multiple step sections. A heterozygous P602L mutation in ATP2A2 was identified as the underlying cause in this family. This mutation and a heterozygous A698V were previously described in AKV. Both mutations were not among the 162 mutations in ATP2A2, which were reported to date in DD. The histopathological study demonstrated in several consecutive step sections of 2 of the 3 studied cases, foci of small suprabasal clefts with acantholytic keratinocytes, some of which were mildly dyskeratotic. These focal features were reminiscent of the basic histopathological characteristics of DD. These shared histopathological features of AKV with DD suggest that AKV and DD are allelic disorders with variable expression of the same disease, although identical mutations in ATP2A2 in AKV and DD were not reported to date.

Photosensitivity disorders in children: part II

Photosensitivity disorders in children encompass a diverse group of diseases. Some inherited disorders manifest with photosensitivity early in life. Specific extracutaneous association may be the clue to diagnosis in this group of pediatric photodermatoses. Part II of this 2-part review covers hereditary photodermatoses caused by defects in nucleotide excision repair, double strand break repair, or localized or systemic biochemical abnormalities. Diagnosis and management of photoaggravated dermatoses are also discussed. Sun protection strategies are required in all patients with evidence of photosensitivity. Early recognition and prompt diagnosis is essential to minimize the long-term complications associated with inadequate photoprotection.

The ATP2A2 gene in patients with Darier's disease: one novel splicing mutation

BACKGROUND

Darier's disease (DD) is a rare, inherited skin disorder characterized by warty papules and plaques over the seborrheic area, such as central trunk, flexures, scalp, and forehead. Mutations in ATP2A2 gene encoding the enzyme sarco/endoplasmic reticulum Ca(2+) ATPase type 2 are responsible for the disease. Here we report two Chinese families affected by DD with two ATP2A2 mutations.

MATERIALS AND METHODS

DNA was extracted from the peripheral blood samples and then subjected to polymerase chain reaction amplification and direct automated DNA sequencing.

RESULTS

A heterozygous G to T transition in the first nucleotide of intron 7 (c.630 + 1G>T) and G to A transversion at nucleotide 2898 in exon 20 of the ATP2A2 gene were identified in two pedigrees, respectively. The former mutation in the splice site is a novel mutation and is thought to lead to aberrant splicing and premature protein truncation. The latter has already been described, which leads to premature termination codons (PTC) (W966X).

CONCLUSION

The results will contribute to the expanding database of ATP2A2 mutations in patients with DD and be useful for inherited counseling and prenatal examination for affected families.

SERCA2-controlled Ca²+-dependent keratinocyte adhesion and differentiation is mediated via the sphingolipid pathway: a therapeutic target for Darier's disease

Darier’s Disease (DD), caused by mutations in the endoplasmic reticulum (ER) Ca²⁺ ATPase ATP2A2 (SERCA2b), is a skin disease that exhibits impaired epidermal cell-to-cell adhesion and altered differentiation. Although previous studies have shown that keratinocyte Ca²⁺ sequestration and fluxes are controlled by sphingolipid signaling, the role of this signaling pathway in DD previously has not been investigated. We show here that sphingosine levels increase and sphingosine kinase (SPHK1) expression decreases after inactivating SERCA2b with the specific SERCA2 inhibitors thapsigargin (TG) or siRNA to SERCA2b. Conversely, inhibiting sphingosine lyase rescues the defects in keratinocyte differentiation, E-cadherin localization, Desmoplakin (DP) translocation, and ER Ca²⁺ sequestration seen in TG-treated keratinocytes. To our knowledge, it was previously unreported that the keratinocyte sphingolipid and Ca²⁺ signaling pathways intersect in ATP2A2- controlled ER Ca²⁺ sequestration, E-cadherin and desmoplakin localization and Ca²⁺ - controlled differentiation, and thus may be important mediators in DD.

A Case of Familial Comedonal Darier's Disease

Darier's disease is a genetic disorder of keratinization with autosomal dominant inheritance. Its appearance is usually in the form of greasy, crusted, keratotic yellow-brown papules and plaques found particularly on seborrheic areas of the body. However, there are some clinical variants showing atypical skin lesions. Here we report an unusual case of Darier's disease, which mainly showed prominent comedonal papules over the face.

Identification of mutation c.632G>A (p.G211D) in the ATP2A2 gene and genotype-phenotype correlation in a large Chinese family with Darier's disease

Darier's disease (DD, MIM 124200) is an autosomal dominant inherited skin disease. Mutations in the ATP2A2 gene, which encoded the sarcoplasmic/endoplasmic reticulum Ca(2+) -ATPase isoform 2 (SERCA2), are responsible for this skin disorder. Here we report the clinical, genetic, and molecular characterization of a large Chinese family with DD. We identified mutation c.632G>A (p.G211D) in the ATP2A2 gene in this family. Genotype-phenotype correlation in available family members provided helpful genetic counseling information for mutation carriers.