Novel mutations in the ATP2C1 gene in two patients with Hailey-Hailey disease

Benign familial chronic pemphigus (Hailey-Hailey disease, HHD) is a rare hereditary condition characterized by development of blisters at sites of friction and in the intertriginous areas. Mutations in the ATP2C1 gene, which encodes the human secretory pathway calcium ATPase 1 (hSPCA1), have been identified as possible causative mutations. Studying Hungarian patients with HHD, we found two novel, distinct, heterozygous mutations. In a 65-year-old man with a 41-year history of severe recurrent symptoms, a single nucleotide insertion, 1085insA, was detected. In a patient whose symptoms were induced by environmental contact allergens, we found a nonsense mutation, Q506X, in exon 17. Our study further illustrates the diversity of mutational events in the pathogenesis of HHD.     

Two novel mutations of the ATP2C1 gene in Chinese patients with Hailey–Hailey disease

Hailey–Hailey disease (HHD; OMIM 169600) is an autosomal dominant blistering disease. Pathogenic mutations in ATP2C1 encoding the human secretory pathway Ca²⁺/Mn²⁺-ATPase protein 1 (hSPCA1) have been identified since 2000. The aim of this study was to report a Chinese pedigree and a sporadic case of HHD and to explore the genetic mutations. The Chinese pedigree and the sporadic case of typical HHD were subjected to mutation detection of ATP2C1. The 27 coding exons and their flanking sequences were amplified and sequenced. The heterozygous C to T transition at nucleotide 2753 in exon 26 and G to T transition at nucleotide 2090 in exon 21 of the ATP2C1 gene were identified in a pedigree and a sporadic case of HHD, respectively. The C2753T transition resulted in a novel nonsense mutation of glutamine codon (CAG) to a stop codon (TAG) at amino acid residue 865 (Q865X) and the G2090T transition resulted in a novel missense mutation of glycine condon (GGA) to Valine (GUA) at amino acid residue 645 (G645V) in hSPCA1. This study should be useful for genetic counseling and prenatal diagnosis for affected families and in expanding the repertoire of ATP2C1 mutations underlying HHD. This work was supported by grant from the Natural Science Foundation of China (30471564).     

ATP2C1 gene mutation analysis in Italian patients with Hailey-Hailey disease

Hailey-Hailey disease (HHD) is a rare autosomal dominant disorder characterized by recurrent skin lesions predominantly involving the body folds. It is caused by heterozygous mutations in the ATP2C1 gene, encoding the human secretory pathway Ca2+/Mn2+-ATPase protein 1 (hSPCA1). In this report we describe the molecular studies performed in eight HHD cases from Italy that led us to identify six different mutations scattered through the ATP2C1 gene in seven of eight cases. Four of the detected mutations were novel. Our results confirm the high allelic heterogeneity of the ATP2C1 gene and support the notion that HHD is a genetically homogeneous disorder. Furthermore, we created a table summarizing all previously reported ATP2C1 mutations, adapting the nomenclature, if needed, according to the guidelines of the Human Genome Variation Society.     

Genetic diagnosis in a Chinese Hailey–Hailey disease pedigree with novel ATP2C1 gene mutation

Hailey–Hailey disease (HHD) is an autosomal dominant skin disorder characterized by recurrent eruption of vesicles and bullae at the sites of friction and in the intertriginous areas. Mutations in the ATP2C1 gene encoding the human secretory pathway calcium ATPase 1 (hSPCA1) have been identified as the causative mutations in HHD. In this study, we used direct sequencing and restriction endonuclease digestion to analyze mutations of the ATP2C1 gene in a Chinese three-generation pedigree. A heterozygous T-to-C transition at nucleotide 1004 in exon 12 of ATP2C1 gene was detected. After summarizing the reported cases with ATP2C1 mutation, we concluded that the T1004C transition resulted in a novel missense mutation of leucine condon (CTG) to proline (CCG) at amino acid residue 335(L335P) in hSPCA1. Here, a genetic diagnosis was made for the proband’s daughter before the clinical presentation. The study realized the molecular diagnosis in the HHD pedigree. Our findings should be useful for genetic counseling and prenatal diagnosis for the affected family and in demonstrating the critical role of the ATP2C1 gene in the pathogenesis of HHD further.     

Hailey-Hailey disease: identification of novel mutations in ATP2C1 and effect of missense mutation A528P on protein expression levels

ATP2C1, encoding the human secretory pathway Ca(2+)-ATPase (hSPCA1), was recently identified as the defective gene in Hailey-Hailey disease (HHD), an autosomal dominant skin disorder characterized by abnormal keratinocyte adhesion in the suprabasal layers of the epidermis. In this study, we used denaturing high-performance liquid chromatography to screen all 28 exons and flanking intron boundaries of ATP2C1 for mutations in 9 HHD patients. Nine different mutations were identified. Five of these mutations, including one nonsense, one deletion, two splice-site, and one missense mutation, have not been previously reported. Recently, functional analysis of a series of site-specific mutants, designed to mimic missense mutations found in ATP2C1, uncovered specific defects in Ca(2+) and/or Mn(2+) transport and protein expression in mutant hSPCA1 polypeptides. In order to investigate the molecular and physiological basis of HHD in the patient carrying missense mutation A528P, located in the putative nucleotide binding domain of the molecule, site-directed mutagenesis was employed to introduce this mutation into the wild-type ATP2C1 (hSPCA1) sequence. Functional analyses of HHD-mutant A528P demonstrated a low level of protein expression, despite normal levels of mRNA and correct targeting to the Golgi, suggesting instability or abnormal folding of the mutated hSPCA1 polypeptides. Analogous to conclusions drawn from our previous studies, these results further support the theory of haploinsufficiency as a prevalent mechanism for the dominant inheritance of HHD, by suggesting that the level of hSPCA1 in epidermal cells is critical.     

Novel mutation in ATP2C1 gene in a Japanese patient with Hailey-Hailey disease

Hailey-Hailey disease (HHD) is an autosomal dominant disorder with recurrent eruption of vesicles and bullae involving predominantly the neck, groin and axillary regions. Histopathology shows suprabasal cleavage in epidermal cells. Recent studies have revealed that HHD is caused by mutations in the ATP2C1 gene encoding a novel Ca(2+) pump. We analyzed mutations of the ATP2C1 gene in 2 Japanese patients with HHD. The diagnosis of HHD was made based on the characteristic clinical features and histopathological evidence. All 27 exons and flanking intron boundaries were amplified by polymerase chain reaction and products analyzed by sequencing. As a result, we identified a novel missense mutation (A1087G) in exon 13 of the ATP2C1 gene in a patient. This mutation led the amino acid change from Thrto Ala in the phosphorylation protein domain. Another patient showed no mutation of the gene. These results demonstrate that a spectrum of ATP2C1 gene mutations is present in Japanese HHD patients.     

Detection and comparison of two types of ATP2C1 gene mutations in Chinese patients with Hailey–Hailey disease

The gene ATP2C1 is identified as the defective gene in Hailey–Hailey disease (HHD). The nonsense and missense are two common types of mutations and have ,respectively, been detected in many HHD patients. The aims of our study were to identify the pathogenic ATP2C1 abnormality in Chinese HHD patients, and to compare nonsense and missense mutations in vivo to provide further understanding of the molecular and the physiological basis of HHD. The nucleotide sequencing of the ATP2C1 gene was performed in HHD patients, unaffected family members and 100 unrelated individuals. Meanwhile, we detected and analyzed the clinical manifestations, the expression of ATP2C1 mRNA and hSPCA1 protein in the two types of mutations. Three heterozygous mutations were identified, including a previously reported nonsense mutation (R799X), two novel missense mutations (D644G) and (R417K). The results of comparisons between two types of mutations showed that the common clinical features, the similarly low-level expressions of ATP2C1 mRNA and hSPCA1 protein, but the ATP2C1 mRNA expression of nonsense mutation was lower than missense mutation and even less than half the level of normal people. Our findings expand the known spectrum of ATP2C1 mutations in HHD. We supported the haploinsufficiency theory as prevalent mechanism in both types of mutations, and believed that the differences of ATP2C1 mRNA expressions in peripheral blood may relate with the type of mutation and reflect the state of illness of patients.     

家族性慢性良性天疱疮ATP2C1基因突变分析

目的探讨家族性慢性良性天疱疮(Hailey-Hailey disease,HHD)患者ATP2C1基因的突变情况。方法应用外周血DNA抽提、PCR和DNA直接测序等方法对中国非同族的2个HHD家系和2例散发患者的ATP2C1基因的27个外显子进行突变检测,并利用Pubmed和中国学术文献网络出版总库检索最近12年来国内外有关HHD患者ATP2C1基因突变分析的文献,统计分析结果。结果入组者发现1例剪切突变118-2A→G,1例错义突变K866T,1例无义突变S212X和1例缺失移码突变356fs2X。综述文献发现ATP2C1基因突变主要集中于3个功能区,此外还发现22外显子是亚洲人种HHD的高风险位点。结论这4例的突变方式目前国内外尚未见报道,可影响转录和翻译的结果,是造成相应家系和散发患者临床病变的特异突变。     

Mutation analysis of ATP2C1 gene in Taiwanese patients with Hailey-Hailey disease

BACKGROUND: Hailey-Hailey disease (HHD) is an autosomal dominant disorder with recurrent eruption of vesicles and bullae involving predominantly the neck, groin and axillary regions. Histopathology shows suprabasal cleavage in epidermal cells. Recent studies have revealed that HHD is caused by mutations in the ATP2C1 gene encoding a novel Ca2+ pump. OBJECTIVES: To analyse the mutations of the ATP2C1 gene in Taiwanese patients with HHD. METHODS: In total, five familial and two sporadic cases of HHD were retrieved from the medical records. The diagnosis of HHD was made based on the characteristic clinical features and histopathological evidence. All 27 exons and flanking intron boundaries were amplified by polymerase chain reaction and products analysed by direct sequencing. RESULTS: We identified six novel mutations and one reported mutation: three deletion mutations (nt884-904del, 1459delCTCA, 1975delA), two non-sense mutations (R39X, R783X), one mis-sense mutation (A730T) and one splicing mutation (483 + 2T-->A). The non-sense mutation R39X had been reported previously; the other six mutations are novel mutations. CONCLUSIONS: These results demonstrate that a spectrum of ATP2C1 gene mutations is present in Taiwanese HHD patients.     

Mutation analysis of the ATP2C1 gene in Taiwanese patients with Hailey-Hailey disease

BackgroundHailey-Hailey disease (HHD) is an autosomal dominant disorder with recurrent pruritic vesicles and erosions, and scaly erythematous plaques, particularly involving intertriginous areas such as the neck, axillae, groins and perineum. Histopathology shows intraepidermal vesiculation with acantholysis in the suprabasal layer. It is caused by heterozygous mutations in the ATP2C1 gene, which encodes for the human secretory pathway Ca²⁺/Mn²⁺ ATPase 1. In this study, we analyze the mutations of the ATP2C1 gene in 26 Taiwanese patients with HHD.MethodsIn total, 21 familial cases from seven families and 5 sporadic cases (including 7 previously reported) were retrieved from the medical records. The diagnosis of HHD was made based on the characteristic clinical features and histopathological evidence. All 27 exons and flanking intron boundaries were amplified by polymerase chain reaction and the products were analyzed by direct sequencing.ResultsWe identified three nonsense mutations (R39X, R468X, R783X), two splice-site mutations (483 + 2t→a, 832G→A), four deletion mutations (nt884-904del, 1459delCTCA, 1874delA, 1975delA) and one missense mutation (A730T). Two unrelated families with nonsense mutation R783X had the comorbidity of chronic schizophrenia since the third decade.ConclusionsWe report two novel mutations (832G→A and 1874delA) of ATP2C1 involved in HHD. The nonsense mutation R783X might represent a mutational “hotspot” in the ATP2C1 gene. The present study demonstrates that a spectrum of ATP2C1 gene mutations is present in Taiwanese HHD patients.     

家族性良性天疱疮患者ATP2C1基因突变研究

目的 探讨3个家族性良性天疱疮家系和1例散发患者的ATP2C1基因突变。方法 采取家系中患病成员外周血,应用外周血细胞DNA抽提、PCR扩增和DNA直接测序等方法检测ATP2C1基因突变情况,用反向测序验证突变,用100例无血缘关系个体作正常人对照。结果 在2个家族性良性天疱疮家系和1例散发患者中发现3个未曾报道的错义突变。家系1第20外显子2048位碱基G→A,导致错义突变R619K;家系2第8外显子853位碱基A→C,导致错义突变T221P;散发患者第23外显子2323位碱基T→C,导致错义突变Y711H。家系中非患病成员和100例无血缘关系正常人均未发现这些改变。在1个家族性良性天疱疮家系未检测到基因突变。结论 发现家族性良性天疱疮3种新的ATP2C1基因突变位点。     

Four novel mutations in ATP2C1 found in Chinese patients with Hailey-Hailey disease

BACKGROUND: Familial benign chronic pemphigus or Hailey-Hailey disease (HHD; OMIM 169600) is an autosomal dominant blistering disease. Pathogenic mutations in ATP2C1 encoding a novel Ca2+ pump have recently been identified. OBJECTIVES: To identify mutations in ATP2C1 in Chinese patients with HHD. METHODS: Eleven unrelated Chinese patients with HHD were subjected to mutation detection in ATP2C1. Eight of them had a family history of HHD. The 27 coding exons and their flanking sequences were amplified and sequenced. RESULTS: Five of the 11 patients were identified to have heterozygous mutations including three nonsense mutations and two splicing mutations in ATP2C1. CONCLUSIONS: Four novel mutations, nonsense mutations S887X and W795X and splicing mutations 118-1 g-->a and 1890+1del(gtgag)ins53, were found in this series of Chinese patients with HHD.     

慢性家族性良性天疱疮五家系ATP2C1基因突变分析

目的：检测中国汉族慢性家族性良性天疱疮5家系ATP2C1基因突变情况。方法：提取5家系中12例患者、13名表型正常及100名正常对照外周血基因组DNA，经PCR扩增后进行DNA测序，并使用Chromas软件解析。结果：家系1中3例患者存在ATP2C1基因第18号外显子c.1738A>G（p.I580V）突变，家系2 中2例患者存在ATP2C1基因第25号外显子c.2416C>T(p.R806*)突变，家系3中3例患者存在ATP2C1基因第15号外显子c.1250G>A（p.R417K）突变，家系4和家系5 中ATP2C1基因未发现突变。上述家系内表型正常个体及100名正常对照中均未检测到相应突变。结论：ATP2C1基因突变可能在3例汉族HHD家系内发挥致病作用。     

慢性家族性良性天疱疮两家系ATP2C1基因突变分析

目的对2例慢性家族性良性天疱疮(HHD)家系ATP2C1基因中可能存在的突变进行鉴别。方法收集2个HHD家系和100份无亲缘关系正常人外周血标本,采用聚合酶链反应方法扩增ATP2C1基因的全部外显子并测序,结果和Genbank中相应序列进行比对。结果家系1中所有患者ATP2C1基因检测到第17号外显子存在一个新的无义突变c.T1431A(p.C477X);家系2中所有患者第24外显子发现一个已报道的移码突变c.2374delTTTG(791LfsX9)。结论两个家系中存在ATP2C1基因的变异,导致编码蛋白的结构和功能发生改变。     

Heterogeneous mutations of the ATP2C1 gene causing Hailey–Hailey disease in Hong Kong Chinese

Background Hailey–Hailey disease (HHD) is a rare autosomal dominant dermatosis. It causes suprabasilar acantholysis leading to vesicular and crusted erosions affecting the flexures. Mutation of ATP2C1 gene encoding the human secretory pathway Ca²⁺/Mn²⁺‐ATPase (hSPCA1) was identified to be the cause of this entity. Objective The aim of this study was to study the mutational profile of the ATP2C1 gene in Hong Kong Chinese patients with HHD. Methods Patients with the clinical diagnosis of HHD proven by skin biopsy were included in this study. Mutation analysis was performed in 17 Hong Kong Chinese patients with HHD. Results Ten mutations in the ATP2C1 gene were found. Six of these were novel mutations. The novel mutations included a donor splice site mutation (IVS22+1G>A); a missense mutation (c.1049A>T); two deletion mutations (c.185_188delAGTT and c.923_925delAAG); an acceptor splice site mutation (IVS21‐1G>C) and an insertion mutation (c.2454dupT). Conclusion The six novel mutations provide additions to the HHD mutation database. No hot‐spot mutation was found and high allelic heterogeneity was demonstrated in the Hong Kong Chinese patients.     

Genetic diagnosis of Hailey–Hailey disease in two Chinese families: novel mutations in the ATP2C1 gene

Hailey–Hailey disease (HHD; OMIM 169600), is an autosomal dominantly inherited disorder characterized by suprabasal cell separation of the epidermis. Mutations in ATP2C1, which encodes the human secretory pathway Ca²⁺/ Mn² ± ATPase protein 1 (hSPCA1), have been identified as the pathogenic gene of HHD without evidence of genetic heterogeneity. In this study, the ATP2C1 gene was screened in two typical Chinese pedigrees with HHD, and two specific novel mutations of the ATP2CL gene were identified. Family 1 had a 16‐base deletion mutation c.1068–1083del16 and family 2 had a substitution mutation c.1982T>G (p.Met661Arg). DNA sequencing of the three descendants of the probands revealed that they all had the normal genotype, indicating that there had been no transmission of the mutation.     

Hailey-Hailey病四个家系的ATP2C1基因突变分析

目的检测Hailey-Hailey病(HHD)4个家系的致病基因ATP2C1,鉴定其突变位点和突变类型。方法采集4个HHD家系成员共9例患者和6名正常人,与100名无关健康对照者外周静脉血各2 ml,提取全基因组DNA。运用聚合酶链反应(PCR)扩增ATP2C1基因的全部28个外显子及其侧翼内含子序列,扩增产物纯化后进行DNA直接测序,BLAST比对分析其突变位点和突变方式。结果在9例HHD患者中共检出了3个ATP2C1基因致病突变:c.888_889ins T(p.296Tfs X2)、c.1330del C(p.443Qfs X33)和c.2416CT(p.Arg806X)。在4个HHD家系的6名正常者和100名健康对照者中均未发现上述突变。结论在9个HHD家系患者中存在2个移码突变(c.888_889ins T和c.1330del C)及1个无义突变(c.2416CT),其中2个移码突变为首次报道。这些突变的发现有助于HHD的诊断,并丰富了HHD相关ATP2C1突变数据库。