Dystrophic Epidermolysis Bullosa: COL7A1 Mutation Landscape in a Multi-Ethnic Cohort of 152 Extended Families with High Degree of Customary Consanguineous Marriages

Dystrophic epidermolysis bullosa is a heritable skin disease manifesting with sub-lamina densa blistering, erosions, and chronic ulcers. COL7A1, encoding type VII collagen, has been identified as the candidate gene for dystrophic epidermolysis bullosa. In this study, we have identified COL7A1 mutations in a large multi-ethnic cohort of 152 extended Iranian families with high degree of consanguinity. The patients were diagnosed by clinical manifestations, histopathology, and immunoepitope mapping. Mutation detection consisted of a combination of single nucleotide polymorphism-based whole-genome homozygosity mapping, Sanger sequencing, and gene-targeted next-generation sequencing. A total of 104 distinct mutations in COL7A1 were identified in 149 of 152 families (98%), 56 (53%) of them being previously unreported. Ninety percent of these mutations were homozygous recessive, reflecting consanguinity in these families. Three recurrent mutations were identified in five or more families, and haplotype analysis suggested a founder effect in two of them. In conclusion, COL7A1 harbored mutations in the overwhelming majority of patients with dystrophic epi-dermolysis bullosa, and most of them in this Iranian cohort were consistent with autosomal recessive inheri-tance. The mutation profile attests to the impact of consanguinity in these families

Gene-Targeted Next Generation Sequencing Identifies PNPLA1 Mutations in Patients with a Phenotypic Spectrum of Autosomal Recessive Congenital Ichthyosis: The Impact of Consanguinity

Heritable forms of ichthyoses, also referred to as generalized Mendelian disorders of cornification, are phenotypically a highly heterogeneous group of conditions caused by mutations in a number of genes playing a role in keratinocyte differentiation and epidermal barrier function (Baden and Digiovanna, 2013; Schmuth et al., 2013). These diseases are characterized by scaling and hyperkeratosis with associated cutaneous and extracutaneous features. This group of disorders is also genetically heterogeneous, with autosomal dominant, autosomal recessive, and X-linked inheritance being described. A specific subgroup of inherited ichthyoses is the autosomal recessive congenital ichthyosis (ARCI), with many newborns presenting as collodion babies, but the subsequent clinical presentation and the spectrum of severity can be highly variable (Richard and Bale, 2014). In the most severe forms, such as harlequin ichthyosis, the disease is often fatal during the early postnatal period, whereas at the other end of the continuum of the spectrum, the disease may present with a relatively mild scaling and variable degree of palmoplantar keratoderma. There is considerable genetic heterogeneity in ARCI, and as many as nine different genes are known to harbor biallelic mutations; these include TGM1, ALOXE3, ALOX12B, NIPAL4, ABCA12, CYP4F22, PNPLA1, LIPN, and CERS3. Previous reports have suggested that mutations in TGM1 account for 30e65% of patients with ARCI, whereas mutations in LIPN, PNPLA1, and CERS3 have been reported only in a few consanguineous families (Richard and Bale, 2014). With the advent of next generation sequencing (NGS), there has been tremendous progress in facilitating the mutation detection in various heritable skin disorders, including ichthyosis (South et al., 2015; Takeichi et al., 2013). In fact, at least 38 different genes have now been suggested to be associated with the ichthyotic phenotypes, either as the primary mutated genes or modifying the phenotypic presentation. To elucidate the genetic basis of ichthyosis in Iran, a country of approximately 80 million people with high prevalence of customary consanguineous marriages, we developed a gene-targeted NGS array consisting of 38 genes reported in association with ichthyosis phenotypes. Identification of specific mutations in a large number of families has allowed us to examine phenotype/genotype correlations with respect to both intra- and interfamilial heterogeneity, in part because of extensive consanguinity in these families. In this study, we identified six distinct and, to our knowledge, previously unreported mutations in the PNPLA1 gene in nine families

Association Between Single Nucleotide Polymorphisms of the Interleukin-4 Gene and Atopic Dermatitis

ABSTRACT Atopic dermatitis (AD) is an inflammatory skin disease in which both genetic and environmental factors seem to be involved. Several studies investigated the association of certain genetic factors with AD in different ethnic groups, but conflicting data were obtained. This study was performed to check the possible association between single nucleotide polymorphisms (SNPs) of interleukin 4 (IL-4) and the IL-4 receptor α chain (IL-4Rα) and AD in a group of Iranian patients. The allele and genotype frequencies of genes encoding for IL-4 and IL-4Rα were investigated in 89 patients with AD in comparison with 139 healthy controls, using methods based on polymerase chain reaction sequence-specific primers. The most frequent alleles of IL-4 in patients were T at -1098 (P&lt;0.001, odds ratio (OR)=2.35), C at -590 (P&lt;0.001, OR=4.84) and C at -33 (P=0.002, OR=2.08). The most frequent genotypes of IL-4 in patients were TT, CC, and CC at positions -1098 (P&lt;0.001, OR=3.59), -590 (P&lt;0.001, OR=31.25) and -33 (P&lt;0.001, OR=3.46), respectively. We found a significant lower frequency of GT at -1098 GT, TC at -590, and TC at -33 in patients. There were no statistically significant differences in the frequency of alleles and genotypes of IL-4Rα gene at position +1902. A strong positive association was seen between TCC haplotype and AD (68% in patients vs. 23.4% in controls, P&lt;0.001, OR=8.91). We detected a significantly lower frequency of TTC, GCC, and TTT haplotypes (P&lt;0.001, OR=0.02, P&lt;0.001, OR=0.40, P&lt;0.001, OR=0.39, respectively) in patients compared to controls. A significant association between the polymorphisms of the IL-4 gene promoter at positions -1098, -590, and -33 and AD was detected in the Iranian population. Key words: atopic dermatitis; polymorphism, single nucleotide; interleukin-4 gene</p

Filaggrin Single Nucleotide Polymorphisms in Atopic Dermatitis

Atopic Dermatitis (AD) is a relapsing chronic pruritic inflammatory disease of skin in which no monogenic cause has been identified so far. Meanwhile Filaggrin (FLG) gene is considered as the most important gene associated with predisposition to the disease.One hundred and six patients with AD and 105 healthy individuals were enrolled in this study. Real time polymerase chain reaction was performed to determine frequencies of alleles and genotype in six variants of FLG gene.Atopic dermatitis (AD) is a relapsing chronic pruritic inflammatory disease of skin for which no monogenic cause has been identified so far. Meanwhile, the filaggrin (FLG) gene is considered as the most important gene associated with predisposition to the disease.One hundred and six patients with AD and 105 healthy individuals were enrolled in this study. Real time polymerase chain reaction was performed to determine frequencies of alleles and genotype in six variants of the FLG gene. The frequencies of allele A in variants of rs3126065, rs2786680, and rs1933063 as well as allele C in variant rs3814300 were 100%. There was no significant difference between allele frequencies in variants rs2485518 and rs3814299. The only genotypes in variants of rs3814299 and rs2485518 were GG and CC, respectively, with no significant difference between the patients and controls. This study demonstrated that there was no significant association between polymorphisms of FLG gene variants and AD.</p

Altered PTEN expression; a diagnostic marker for differentiating normal, hyperplastic and neoplastic endometrium

Abstract Background Different molecular alterations have been described in endometrioid endometrial carcinoma (EECA). Among them the most frequently altered is loss of the PTEN protein, a tumor suppressor gene. The purpose of this study was to evaluate the expression pattern of PTEN gene in normal, hyperplastic and neoplastic endometrium. Methods In a study in a referral gynecologic hospital in Tehran, Iran, immunohistochemical (IHC) evaluation of PTEN was performed on 87 consecutive specimens to the following three groups; group A- normal proliferative endometrium(n = 29); group B- hyperplastic endometrium [including simple hyperplasia without atypia(n = 21) and complex hyperplasia with atypia (n = 8)] and group C- EECA(n = 29). Immunostaining of cells was analyzed by arbitrary quantitative methods according to both slide's area staining and intensity of color reaction. Results PTEN immunoreactivity was present in all normal proliferative endometrium, all simple hyperplasia, 75% of atypical complex hyperplasia and in 48% of EECA (P &lt; 0.001). The intensity of PTEN reaction was significantly higher in group with proliferative endometrium than hyperplastic endometrium and EECA (P &lt; 0.001). Conclusion PTEN expression was significantly higher in cyclical endometrium than in atypical hyperplasia and endometrioid carcinoma.</p