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Background: The combination of palmoplantar keratoderma and woolly hair is uncommon and reported as part of Naxos and Carvajal syndromes, both caused by mutations in desmosomal proteins and associated with cardiomyopathy. We describe two large consanguineous families with autosomal-recessive palmoplantar keratoderma and woolly hair, without cardiomyopathy and with no mutations in any known culprit gene. The aim of this study was to find the mutated gene in these families., Methods and Results: Using whole-exome sequencing, we identified a homozygous missense c.2009C>T mutation in KANK2 in the patients (p.Ala670Val). KANK2 encodes the steroid receptor coactivator (SRC)-interacting protein (SIP), an ankyrin repeat containing protein, which sequesters SRCs in the cytoplasm and controls transcription activation of steroid receptors, among others, also of the vitamin D receptor (VDR). The mutation in KANK2 is predicted to abolish the sequestering abilities of SIP. Indeed, vitamin D-induced transactivation was increased in patient's keratinocytes. Furthermore, SRC-2 and SRC-3, coactivators of VDR and important components of epidermal differentiation, are localised to the nucleus of epidermal basal cells in patients, in contrast to the cytoplasmic distribution in the heterozygous control., Conclusions: These findings provide evidence that keratoderma and woolly hair can be caused by a non-desmosomal mechanism and further underline the importance of VDR for normal hair and skin phenotypes., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Monilethrix is a genetic hair shaft disorder that causes a dystrophic alopecia. Mutations causing autosomal dominant monilethrix have been found in the helix initiation and helix termination motifs of the type II hair keratins KRT81, KRT83 and KRT86. Mutations in DSG4 are linked to recessive transmission., Objectives: We investigated a large Tasmanian family demonstrating autosomal dominant monilethrix with incomplete penetrance in order to identify the responsible genetic mutation. As only some affected hairs were moniliform, analysis was undertaken to demonstrate a deficit in the tensile strength of nonmoniliform hairs., Methods: One hundred and twenty family members were examined. Light microscopy of hair samples was used to support clinical diagnoses. Linkage and gene sequencing studies were then undertaken. Nonbeaded fibres were analysed using the Single Fibre Analyser 3 (SIFAN 3)., Results: We identified a novel A280V (c.839C > T substitution) mutation in the coil 2A region of KRT86. This is the first mutation located in a region other than the helix initiation or termination motifs. The A280V mutation was identified in both affected and clinically unaffected family members. Nonmoniliform hairs demonstrated reduced elasticity among both affected and unaffected individuals carrying the A280V mutation., Conclusions: This is the first mutation located in a region other than the helix initiation or termination motifs, thus expanding the spectrum of mutations and highlighting the importance of molecular diagnosis in monilethrix., (© 2012 The Authors. BJD © 2012 British Association of Dermatologists.)

Objective: Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE syndrome) is an autoinflammatory syndrome recently described in children. We undertook this study to investigate the clinical phenotype, genetic cause, and immune dysregulation in 9 CANDLE syndrome patients., Methods: Genomic DNA from all patients was screened for mutations in PSMB8 (proteasome subunit β type 8). Cytokine levels were measured in sera from 3 patients. Skin biopsy samples were evaluated by immunohistochemistry, and blood microarray profile and STAT-1 phosphorylation were assessed in 4 patients and 3 patients, respectively., Results: One patient was homozygous for a novel nonsense mutation in PSMB8 (c.405C>A), suggesting a protein truncation; 4 patients were homozygous and 2 were heterozygous for a previously reported missense mutation (c.224C>T); and 1 patient showed no mutation. None of these sequence changes was observed in chromosomes from 750 healthy controls. Of the 4 patients with the same mutation, only 2 shared the same haplotype, indicating a mutational hot spot. PSMB8 mutation-positive and -negative patients expressed high levels of interferon-γ (IFNγ)-inducible protein 10. Levels of monocyte chemotactic protein 1, interleukin-6 (IL-6), and IL-1 receptor antagonist were moderately elevated. Microarray profiles and monocyte STAT-1 activation suggested a unique IFN signaling signature, unlike in other autoinflammatory disorders., Conclusion: CANDLE syndrome is caused by mutations in PSMB8, a gene recently reported to cause "JMP" syndrome (joint contractures, muscle atrophy, microcytic anemia, and panniculitis-induced childhood-onset lipodystrophy) in adults. We extend the clinical and pathogenic description of this novel autoinflammatory syndrome, thereby expanding the clinical and genetic disease spectrum of PSMB8-associated disorders. IFN may be a key mediator of the inflammatory response and may present a therapeutic target., (Copyright © 2012 by the American College of Rheumatology.)