1/45. Detection of human papillomavirus type 10 dna in eccrine syringofibroadenomatosis occurring in Clouston's syndrome.Syringofibroadenomatosis is often associated with an underlying condition such as diabetes mellitus or hidrotic ectodermal dysplasia. By reason of these associations, a reactive or hamartomatous cause is suspected. We report a case of a 71-year-old woman with Clouston's syndrome in whom progressive multiple palmoplantar syringofibroadenomas developed over a 10-year period. The syringofibroadenomas formed flat-topped papules simulating verruca plana; the widespread distribution and chronic progressive course resembled epidermodysplasia verruciformis. Contiguous with the syringofibroadenoma's characteristic epithelial-stromal proliferation were epidermal changes of verruca plana. Evidence of human papillomavirus (HPV) infection was verified by immunolabeling with antibodies to bovine papillomavirus type 1 and detection of HPV 10 viral dna by means of polymerase chain reaction. Rather than a hamartomatous process, these findings suggest that syringofibroadenomas occurring in the setting of Clouston's syndrome could represent an HPV-induced epithelial proliferation.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
2/45. A case of hypohidrotic ectodermal dysplasia.Hypohidrotic ectodermal dysplasia (HED) is a rare, hereditary, congenital disease that affects several ectodermal structures. It is characterised by the following: anhidrosis or hypohidrosis, dental abnormalities, hypotrichosis, and a characteristic facies. The face shows prominent frontal bosses, supraorbital ridges and depressed bridges. We experienced a case of hypohidrotic ectodermal dysplasia in a 43-year-old male who had four characteristic features. A skin biopsy from the palm showed a total absence of the eccrine glands. The diagnosis was made on the basis of clinical features and skin biopsy findings.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
3/45. A mutation detection strategy for the human keratin 6A gene and novel missense mutations in two cases of pachyonychia congenita type 1.pachyonychia congenita type 1 (PC-1) is an autosomal dominant ectodermal dysplasia characterized by hypertrophic nail dystrophy, focal non-epidermolytic palmoplantar keratoderma and variable features of oral leukokeratosis and follicular keratosis. Previously, we have shown that this disease can be caused by mutations in type I keratin K16 and one mutation has been reported in its type II keratin expression partner, K6a. mutation analysis for K6a has been hampered by the presence of multiple copies of the K6 gene in the human genome, of which some are expressed and others are pseudogenes. Here, we describe a mutation detection strategy where the entire KRT6A gene, approximately 7 kb, is specifically amplified by long-range PCR. Using this technique, we have detected two novel mutations in the 1A domain of the K6a polypeptide, N171K and F174S. Mutations were confirmed in the affected individuals and were excluded from 50 unaffected unrelated individuals by restriction enzyme analysis of KRT6A PCR products. Additionally, mutation N171K was confirmed by RT-PCR in mRNA derived from lesional palmoplantar epidermis of an affected individual, confirming the specificity of the genomic PCR for the functional K6a gene. This, together with a similar strategy which we have developed for the K16 gene, provide a robust system for mutation detection and prenatal diagnosis for patients with PC-1.- - - - - - - - - - ranking = 2keywords = palm (Clic here for more details about this article) |
4/45. Identification of sporadic mutations in the helix initiation motif of keratin 6 in two pachyonychia congenita patients: further evidence for a mutational hot spot.pachyonychia congenita (PC) is a rare, autosomal dominant, ectodermal dysplasia characterized most distinctly by the presence of symmetric nail hypertrophy. In the Jadassohn-Lewandowsky form, or PC-1, additional cutaneous manifestations may include palmoplantar hyperkeratosis, hyperhidrosis, follicular keratoses, and oral leukokeratosis. Mutations have previously been identified in the 1A helix initiation motif of either keratin 6 or keratin 16 in patients with PC-1. In the current study, we have identified 2 sporadic, heterozygous mutations in the 1A helix region of the K6 isoform (K6a). The first mutation identified was a 3 base pair deletion (K6adelta N171). The second mutation was a C-to-A transversion resulting in an amino acid substitution (K6a N171K). These data, in combination with previous reports, provide further evidence that this location is a mutational hot spot.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
5/45. Cloning of multiple keratin 16 genes facilitates prenatal diagnosis of pachyonychia congenita type 1.pachyonychia congenita type 1 (PC-1) is an autosomal dominant ectodermal dysplasia characterized by severe nail dystrophy, focal non-epidermolytic palmoplantar keratoderma (FNEPPK) and oral lesions. We have previously shown that mutations in keratin K16 cause fragility of specific epithelia resulting in phenotypes of PC-1 or FNEPPK alone. These earlier analyses employed an RT-PCR approach to avoid amplification of K16-like pseudogenes. Here, we have cloned the K16 gene (KRT16A) and two homologous pseudogenes (psiKRT16B and psiKRT16C), allowing development of a genomic mutation detection strategy based on a long-range PCR, which is specific for the functional K16 gene. We report a novel heterozygous 3 bp deletion mutation (388del3) in K16 in a sporadic case of PC-1. The mutation was detected in genomic dna and confirmed at the mRNA level by RT-PCR, showing that our genomic PCR system is reliable for K16 mutation detection. Using this system, we carried out the first prenatal diagnosis for PC-1 using CVS material, correctly predicting a normal fetus. This work will greatly improve K16 mutation analysis and allow predictive testing for PC-1 and the related phenotype of FNEPPK.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
6/45. Novel proline substitution mutations in keratin 16 in two cases of pachyonychia congenita type 1.pachyonychia congenita (PC) is a group of inherited ectodermal dysplasias, the characteristic phenotype being hypertrophic nail dystrophy. Two main clinical subtypes, PC-1 and PC-2, are inherited as autosomal dominant disorders, but other less well characterized clinical forms also exist. The PC-1 phenotype may be distinguished by the absence of the epidermal cysts found in PC-2, and it has been shown to be caused by mutations in either keratin K16 or its expression partner, the K6a isoform of K6. Mutations in K16 have also been shown to cause a milder related phenotype, focal non-epidermolytic palmoplantar keratoderma. Recently, we have developed a long-range polymerase chain reaction (PCR) strategy which allows specific amplification of the entire functional K16 gene (KRT16A), without amplification of the two K16 pseudogenes (psiKRT16B and psiKRT16C), enabling mutation analysis based on genomic dna. Here, using this methodology, we describe novel mutations R127P and Q122P in the helix 1A domain of K16 in two families presenting with PC-1. Both mutations were excluded from 50 normal unrelated individuals by restriction enzyme analysis of K16 PCR fragments. In one family, ultrastructural analysis was performed, revealing distinctive tonofilament abnormalities. Specifically, keratin filament bundles were greatly condensed, but did not form the dense amorphous aggregates seen in a number of other keratin disorders. In the second kindred, autosomal dominant cataract was present in some but not all members affected by PC. As the cataract phenotype did not fully cosegregate with the K16 mutation, and given that K16 is not expressed in the lens, these two phenotypes may be coincidental.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
7/45. Eruptive vellus hair cyst and epidermoid cyst in a patient with pachyonychia congenita.We report the first case of pachyonychia congenita (PC) associated with both eruptive vellus hair cyst (EVHC) and epidermoid cyst. The patient is a 12-year-old Japanese girl who presented with two natal teeth at birth. She had thickening and discoloration of the fingernails and toenails, plantar hyperkeratosis, palmar-plantar hyperhidrosis and multiple cutaneous cysts. Histologic examination revealed EVHC and epidermoid cyst.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
8/45. Novel keratin 17 mutations in pachyonychia congenita type 2.pachyonychia congenita type 2 is an inherited ectodermal dysplasia characterized by hypertrophic nail dystrophy and multiple pilosebaceous cysts. Focal nonepidermolytic palmoplantar keratoderma, natal teeth, and pili torti may also be present. Epithelial tissues affected in pachyonychia congenita type 2 express the keratin pair K6b/K17. Here, we report three novel heterozygous mutations in the K17 gene (KRT17A) in patients presenting with pachyonychia congenita type 2. These mutations, R94-98del (deletion of the peptide sequence RLASY) and missense mutations R94P and L95Q, are all within the 1A domain hotspot for pathogenic keratin mutations.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
9/45. Almost complete absence of the scalp and body hair in association with oligodontia and zygodactylous palmar triradii.We describe an 18-year-old girl with a distinctive facial appearence, almost complete absence of the scalp and body hair, absence of the eyebrows and eyelashes, oligodontia, conically shaped maxillary central incisors and zygodactylous palmar triradii suggesting for syndactyly type I.- - - - - - - - - - ranking = 5keywords = palm (Clic here for more details about this article) |
10/45. A novel connexin 30 mutation in Clouston syndrome.Clouston syndrome (hidrotic ectodermal dysplasia) is an autosomal dominant ectodermal dysplasia characterized by alopecia, palmoplantar hyperkeratosis, and nail dystrophy. Recently, mutations in the GJB6 gene encoding the gap junction protein connexin 30 have been shown to cause this disorder. To date, all mutations have involved two codons: G11R and A88V. Here, we report a novel mutation V37E within the first transmembrane domain of connexin 30 in a spontaneous case of Clouston syndrome. The mutation was detected in genomic dna, confirmed in reverse transcription polymerase chain reaction products, and was excluded from 100 ethnically matched control individuals by restriction enzyme analysis.- - - - - - - - - - ranking = 1keywords = palm (Clic here for more details about this article) |
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