A novel variant in the GJB6 gene in a large Chinese family with a unique phenotype of Clouston syndrome.

Clouston syndrome (OMIM #129500), also known as hidrotic ectodermal dysplasia type 2, is a rare autosomal dominant skin disorder. To date, four mutations in the GJB6 gene, G11R, V37E, A88V, and D50N, have been confirmed to cause this condition. In previous studies, the focus has been mainly on gene sequencing, and there has been a lack of research on clinical manifestations and pathogenesis. To confirm the diagnosis of this pedigree at the molecular level and summarize and analyse the clinical phenotype of patients and to provide a basis for further study of the pathogenesis of the disease, we performed whole-exome and Sanger sequencing on a large Chinese Clouston syndrome pedigree. Detailed clinical examination included histopathology, hair microscopy, and scanning electron microscopy. We found a novel heterozygous missense variant (c.134G>C:p.G45A) for Clouston syndrome. We identified a new clinical phenotype involving all nail needling pain in all patients and found a special honeycomb hole structure in the patients' hair under scanning electron microscopy. Our data reveal that a novel variant (c.134G>C:p.G45A) plays a likely pathogenic role in this pedigree and highlight that genetic testing is necessary for the diagnosis of Clouston syndrome.

A novel splice-site variant of the LAMB3 gene is associated with junctional epidermolysis bullosa

Background: Junctional epidermolysis bullosa (JEB) is a rare inherited genetic disorder in which pathogenic mutations are mostly located within exons of the associated genes. This report describes a novel variant located at a splice site. Objectives: To confirm the diagnosis of the JEB family and identify the pathogenic variant. Materials & Methods: We collected clinical data and DNA from the members of the family. Whole-exome sequencing (WES) and Sanger sequencing were used to detect gene variants. The pMINI minigene system was used to design in vitro experiments, to confirm the pathogenic variants. Results: A novel splice-site variant (c.629-12T>G) of the LAMB3 gene was detected in all patients and was shown to be a pathogenic variant. Conclusion: The diagnosis of JEB should depend on gene sequencing, and variants at splice sites may also cause the disease.

Costello syndrome with special cutaneous manifestations and HRAS G12D mutation: A case report and literature review.

BACKGROUND: Costello syndrome (CS, OMIM 218040) is a rare congenital disorder caused by mutations in HRAS. Previous studies reported that approximately 80% of patients with CS share the same pathogenic variant in HRAS gene in c.34G> A (p.G12S). Here, we report a CS patient with c.34G> A (p.G12D) variant in HRAS gene and she presented with special manifestation. METHODS AND RESULTS: We describe a 31-year-old female patient who presented with distinctive facial appearance, intellectual disability, dental abnormalities, hyperkeratosis of palmer and planter, loose skin at birth, papillomata on the face and nipples. The whole-exome sequencing (WES) technology provided by Haotian Biotechnology (China) confirmed p.G12D variant in HRAS gene. To elucidate the typical features of CS with p.G12D variant, we further reviewed these previously reported cases and found that patients with G12D variant died within three months after birth due to multiple organ failure. They had the typical facial characteristics, failure to thrive, skin and cardiac abnormalities, and gene testing confirmed the diagnosis of CS. CONCLUSION: To the best of our knowledge, this is the first article to report a patient with a p.G12D variant that had special but mild manifestation. Moreover, this report and literature review casts new light on the clinical features of p.G12D variant.

Intermittent Asymptomatic Fever in a Psoriasis Patient.

Acitretin, an active metabolite of etretinate, is the most widely used systemic retinoid in the treatment of psoriasis. Several side effects of acitretin have been reported such as teratogenicity, cheilitis, xerosis, dyslipidemia, and photosensitivity. Here, we reported a case of acitretin-induced intermittent asymptomatic fever in a 79-year-old male psoriasis patient. To the best of our knowledge, only one such case has been reported in the literature so far. We report our case to draw clinical attention that acitretin may cause drug fever, which might not be a rare phenomenon.

Association of the novel susceptible locus rs9266150 with clinical features of psoriasis vulgaris in the Chinese Han population.

Psoriasis is a chronic multifactorial disease and is considered to be strongly associated with the major histocompatibility complex (MHC) region. We have discovered an independent, novel and susceptible psoriasis risk HLA loci, rs9266150; P = 4.52 × 10-9 for the first time. In this study, we aimed to verify the relationship between the susceptible locus and the subphenotypes of psoriasis vulgaris (PV), including geographic location, gender, age of onset, family history and present skin lesion types (chronic plaque and guttate). To investigate the distribution and association of the rs9266150 gene with clinical phenotypes of PV in Chinese Han population, we conducted an analysis in case-control and case-only subjects in the 9906 controls and 8744 cases by MHC targeted sequencing stratified analysis in this study. Significant associations were found with a northern geographic location in the case-only (P = 1.97 × 10-4 ) and the subphenotype-control analyses (P = 5.57 × 10-5 ), males in the case-only (P = 4.77 × 10-3 ) and the subphenotype-control analyses (P = 7.31 × 10-4 ), and guttate psoriasis in the case-only (P = 4.08 × 10-3 ) and the subphenotype-control analyses (P = 1.27 × 10-3 ). There were no significant differences observed between the age of onset (OR = 1.062, 95% CI: 0.9725-1.16, P = 1.8 × 10-1 ) and the family history of psoriasis (OR = 0.981, 95% CI: 0.9048-1.064, P = 6.43 × 10-1 ). The recessive model provided the best fit for rs9266150 (P = 4.38 × 10-7 ). Our results implied that rs9266150 might not only play an important role in the development of psoriasis, but also be positively associated with the geographic location, gender and present skin lesion in the Chinese population.

Genotype combination contributes to psoriasis: An exhaustive algorithm perspective.

Researchers have learned that nearly all conditions and diseases have a genetic component. With the benefit of technological advances, many single-nucleotide polymorphisms (SNPs) have been found to be associated with the risk of complex disorders by using genome wide association studies (GWASs). Disease-associated SNPs are sometimes shared by healthy controls and cannot clearly distinguish affected individuals from unaffected ones. The combined effects of multiple independent SNPs contribute to the disease process, but revealing the relationship between genotype and phenotype based on the combinations remains a great challenge. In this study, by considering the disease prevalence rate, we conducted an exhaustive process to identify whether a genotype combination pattern would have a decisive effect on complex disorders. Based on genotype data for 68 reported SNPs in 8,372 psoriasis patients and 8,510 healthy controls, we found that putative causal genotype combination patterns (CGCPs) were only present in psoriasis patients, not in healthy subjects. These results suggested that psoriasis might be contributed by combined genotypes, complementing the traditional modest susceptibility of a single variant in a single gene for a complex disease. This work is the first systematic study to analyze genotype combinations based on the reported susceptibility genes, considering each individual among the cases and controls from the Chinese population, and could potentially advance disease-gene mapping and precision medicine due to the causality relationship between the candidate CGCPs and complex diseases.

Correlation analysis of the HLA-DPB1*05:01 and BTNL2 genes within the histocompatibility complex region with a clinical phenotype of psoriasis vulgaris in the Chinese Han population.

BACKGROUND: The human major histocompatibility complex (MHC) is known to be highly polymorphic and has been identified to be associated with numerous diseases. The HLA-DPB1 and BTNL2 genes were associated with psoriasis for the first time. The present study aims to investigate the relevance of the HLA-DPB1 and BTNL2 genes with respect to clinical phenotypes of psoriasis vulgaris (PV). METHODS: To investigate whether the HLA-DPB1 and BTNL2 polymorphisms were associated with clinical phenotypes of PV in Chinese Han population, we conducted an analysis in case-controls and case-only subjects (9906 controls and 8744 cases) via MHC targeted sequencing stratified analysis. RESULTS: In cases and controls, analysis showed that the genotype of HLA-DPB1*05:01 was associated with type of guttate [p = 3.914 × 10-2 , odds ratio (OR = 0.9335)] and northern region (p = 1.182 × 10-3 , OR = 0.9108). In the case-only analysis, the genotype of HLA-DPB1*05:01 was significantly correlated with geographical region (p = 1.36 × 10-3 , OR = 1.134). In cases and controls, analysis showed that the genotype of BTNL2 (rs 41355746) was associated with being male (p = 2.563 × 10-2 , OR = 0.8897), early-onset (p = 9.399 × 10-3 , OR = 0.8856), guttate (p = 2.469 × 10-2 , OR = 0.8558) and family history (p = 1.51 × 10-4 , OR = 0.772). In the case-only analysis, the genotype of BTNL2 (rs41355746) was significantly correlated with family history (p = 1.768 × 10-3 , OR = 0.757) and age of onset (p = 3.818 × 10-2 , OR = 1.195). CONCLUSIONS: The results of the present study indicate that the HLA-DPB1*05:01 gene was associated with the geographical region of PV and the BTNL2 gene was significantly associated with family history and age of onset of PV. In conclusion, the HLA-DPB1*05:01 and BTNL2 genes might be responsible for the complicacy of clinical features.