OBJECTIVE: To investigate the clinical characteristics and genetic etiology of eight members from a pedigree affected with epidermolysis bullosa (EB). METHODS: A girl presented with recurrent, unexplained blisters on the palmar and plantar skin for 8 years and sought medical care in October 2024 was enrolled as the study subject. A retrospective study was conducted to collect the child's clinical data, and a detailed medical history was taken for her family members. Peripheral venous blood samples were collected from the child and her parents for genomic DNA extraction. Whole-exome sequencing (WES) was performed. Candidate variant was validated by Sanger sequencing. The pathogenicity of the candidate variants was classified in accordance with the Standards and Guidelines for the Interpretation of Sequence Variants issued by the American College of Medical Genetics and Genomics (ACMG, hereinafter referred to as the "ACMG Guidelines"). This study was approved by the Medical Ethics Committee of the 980th Hospital of the Joint Logistics Support Force of the Chinese People's Liberation Army (Ethics No.: 2019-KY-01). RESULTS: The proband was an 8-year-and-4-month-old female. Four months after birth, she had developed recurrent blisters on the palmar and plantar skin without obvious triggers, accompanied by significant pain. Symptoms were more severe in summer and slightly relieved in winter. Although symptomatic treatment could alleviate the symptoms, she was unable to participate in physical activities. A detailed family history revealed that her great-grandfather, grandfather, father, half-brother, great-aunt, great-aunt's son and two grandsons, as well as her aunt and aunt's son, had similar clinical manifestations. WES revealed that she has harbored a heterozygous c.556-16(IVS1)C>G (NM_000424.4) variant in the KRT5 gene, which was identified as a splice site mutation. Reverse transcription sequencing confirmed that this variant can disrupt normal splicing, resulting in retention of a 15 bp sequence in the first intron. Sanger sequencing demonstrated that the variant was inherited from the father, and the 6 aforementioned relatives with similar phenotypes have all carried the same variant (the great-grandfather, grandfather, and great-aunt had declined genetic testing due to advanced age). Based on the ACMG guidelines, this variant was classified as pathogenic (PS3+PM2_Supporting+PP3+PP1_strong). CONCLUSION Patients with epidermolysis bullosa simplex may exhibit clinical features including blistering on the skin or mucous membranes of friction-prone sites (e.g. hands, feet, elbows, and knees) following minor trauma or friction, as well as increased skin fragility. The c.556-16(IVS1)C>G (rs376462752) variant of the KRT5 gene probably underlay the pathogenesis of EB in this child. Above findings have enriched the mutational spectrum of the KRT5 gene.
Child ; Female ; Humans ; Infant ; Male ; China ; Epidermolysis Bullosa Simplex/genetics* ; Exome Sequencing ; Keratin-5/genetics* ; Mutation ; Pedigree ; Retrospective Studies ; East Asian People/genetics*

Epidermolysis bullosa (EB) is a group of clinically and genetically heterogeneous diseases characterized by trauma-induced mucocutaneous fragility and blister formation. Here, we investigated five Chinese families with EB, and eight variants including a novel nonsense variant (c.47G>A, p.W16*) in LAMA3, a known recurrent variant (c.74C>T, p.P25L) in KRT5, 2 novel (c.2531T>A, p.V844E; c.6811_6814del, p.R2271fs) and 4 known (c.6187C>T, p.R2063W; c.7097G>A, p.G2366D; c.8569G>T, p.E2857*; c.3625_3635del, p.S1209fs) variants in COL7A1 were detected. Notably, this study identified a nonsense variant in LAMA3 that causes EB within the Chinese population and revealed that this variant resulted in a reduction in LAMA3 mRNA and protein expression levels by nonsense-mediated mRNA decay. Our study expands the mutation spectra of Chinese patients with EB.
Humans ; Asian People/genetics* ; China ; Collagen Type VII/genetics* ; Epidermolysis Bullosa/genetics* ; Epidermolysis Bullosa Dystrophica/genetics* ; Keratin-5/genetics* ; Mutation ; Pedigree ; Laminin/genetics*

Objective To investigate the clinical characteristics and genetic mutations in Kindler syndrome(KS)and provide a theoretical basis for the diagnosis and treatment of KS. Methods The clinical data of one case of KS from Peking Union Medical College Hospital and 185 cases reported in literature were collected. The gene mutation types,patient clinical data,and tumor characteristics were statistically analyzed. Results A total of 186 cases were enrolled,including 110 males and 76 females,with the mean age of(28±16)years. The data of gene mutation and specific clinical manifestations were available in 151 and 94 patients,respectively. The main clinical manifestations of KS included poikiloderma,occurrence of blister in childhood,and photosensitivity,and the secondary clinical manifestations included oral inflammation,palmoplantar keratoderma,webbing/pseudoainhum,dysphagia,urethral stricture and so on.Oral inflammation(r=0.234,P=0.023),palmoplantar keratoderma(r=0.325,P=0.001),webbing/pseudoainhum(r=0.247,P=0.016),dysphagia(r=0.333,P=0.001),urethral stricture(r=0.280,P=0.006)were significantly correlated with age,showing significantly higher incidence in the patients over 32 years old.Urethral stricture(χ²=11.292,P=0.001)and anal stenosis(χ²=4.014,P=0.045)were significantly correlated with sex,with higher incidence in males.Eighty different mutations were found in 151 patients,and the most common gene mutation was c.676C>T.Forty-one tumors occurred in 27 patients,among which squamous cell carcinoma accounted for 92.7%. The gene mutation site had no significant correlation with squamous cell carcinoma or patient country. Conclusions The c.676C>T in FERMT1 gene is the most common mutation in KS.The patients are prone to squamous cell carcinoma and mainly attacked at the exposure sites(hand and mouth).
Adolescent ; Adult ; Ainhum ; Blister ; Carcinoma, Squamous Cell ; Child ; Constriction, Pathologic ; Deglutition Disorders/complications* ; Epidermolysis Bullosa ; Female ; Humans ; Inflammation ; Keratoderma, Palmoplantar/complications* ; Male ; Membrane Proteins ; Mutation ; Neoplasm Proteins/genetics* ; Periodontal Diseases ; Photosensitivity Disorders ; Urethral Stricture/complications* ; Young Adult

OBJECTIVE: To perform gene mutation analysis in a Chinese pedigree with dystrophic epidermolysis bullosa pruriginosa (DEB-Pr), and explore phetotype, genotype, and genotypes-phenotypes relationship of DEB-Pr. METHODS: Potential variants of the COL7A1 gene were detected by skin targeted sequencing panel and verified by Sanger sequencing. The pathogenicity of the variation was analyzed. RESULTS: Compound heterozygous variants, c.4128delT and c.8234G>A, were detected in the COL7A1 gene of the two patients. The c.4128delT(p.Pro1376fs) variant was derived from their mother and unreported previously. According to the American College of Medical Genetics and Genomics Standards and Guidelines, it was suggested to be a pathogenic mutation. The c.8234G>A(p.Arg2745Gln) variant was derived from their father, and possibly is a pathogenic variation. CONCLUSION In this study, the compound heterozygous variants of c.4128delT(p.Pro1376fs) and c.8234G>A(p.Arg2745Gln) of the COL7A1 gene probably underlies the disease in this patient and his sister. And our study expands the database on mutations of DEB-Pr.
Collagen Type VII/genetics* ; Epidermolysis Bullosa Dystrophica/genetics* ; Female ; Humans ; Male ; Mutation ; Pedigree ; Phenotype

OBJECTIVE: To carry out genetic testing and prenatal diagnosis for a family affected with recessive dystrophic epidermolysis bullosa (RDEB). METHODS: All exons of the COL7A1 gene and their flanking regions were subjected to PCR and Sanger sequencing. Suspected variant was validated in family members, based on which prenatal diagnosis was provided. RESULTS: Sanger sequencing found that the proband has carried two variants of the COL7A1 gene, namely c.7289delC (p.Pro2430Glnfs*36) and c.7474C>T (p.Arg2492*), which were respectively derived from his mother and father. The same variants were not found among 100 healthy controls. By prenatal diagnosis, the fetus was found to have inherited the c.7474C>T (p.Arg2492*) variant from its father. CONCLUSION The pathogenic variants of the COL7A1 gene of the RDEB family were clarified, based on which prenatal diagnosis was provided.
Child ; Collagen Type VII ; genetics ; Epidermolysis Bullosa Dystrophica ; genetics ; Exons ; Female ; Genes, Recessive ; Genetic Testing ; Humans ; Male ; Mutation ; Pregnancy ; Prenatal Diagnosis ; Sequence Analysis, DNA

OBJECTIVETo determine the molecular etiology for a Chinese pedigree affected with epidermolysis bullosa simplex (EBS).

METHODSTarget region sequencing using a hereditary epidermolysis bullosa capture array combined with Sanger sequencing and bioinformatics analysis were used. Mutation taster, PolyPhen-2, Provean, and SIFT software and NCBI online were employed to assess the pathogenicity and conservation of detected mutations. One hundred healthy unrelated individuals were used as controls.

RESULTSTarget region sequencing showed that the proband has carried a unreported heterozygous c.1234A>G (p.Ile412Val) mutation of the KRT14 gene, which was confirmed by Sanger sequencing in other 8 affected individuals but not among healthy members of the pedigree. Bioinformatics analysis indicated that the mutation is highly pathogenic. Remarkably, 3 members of the family (2 affected and 1 unaffected) have carried a heterozygous c.1237G>A (p.Ala413Thr) mutation of the KRT14 gene, which was collected in Human Gene Mutation Database (HGMD). Bioinformatics analysis indicated that the mutation may not be pathogenic. Both mutations were not detected among the 100 healthy controls.

CONCLUSIONThe novel c.1234A>G(p.Ile412Val) mutation of the KRT14 gene is probably responsible for the disease, while c.1237G>A (p.Ala413Thr) mutation of KRT14 gene may be a polymorphism. Compared with Sanger sequencing, target region capture sequencing is more efficient and can significantly reduce the cost of genetic testing for EBS.

Adult ; Amino Acid Sequence ; Case-Control Studies ; Epidermolysis Bullosa Simplex ; genetics ; Female ; Humans ; Keratin-14 ; genetics ; Male ; Mutation ; genetics ; Pedigree ; Young Adult

OBJECTIVETo identify keratin 5 (K5) and keratin 14 (K14) gene mutations in a family affected with epidermolysis bullosa simplex with mottled pigmentation.

METHODSGenomic DNA was extracted from peripheral blood samples obtained from eleven patients from the family and controls. All the exons of K5 and K14 genes were amplified using polymerase chain reaction (PCR) and directly sequenced.

RESULTSBy DNA sequence analysis, a missense mutation in K5 gene (c.237C>T) was detected. The same mutation was not found in non-affected members from the family and normal controls.

CONCLUSIONMutation in K5 gene (c.237C>T) may be responsible for the development of disease in this family.

Base Sequence ; DNA Mutational Analysis ; Epidermolysis Bullosa Simplex ; genetics ; pathology ; Exons ; Female ; Humans ; Hyperpigmentation ; genetics ; pathology ; Keratin-14 ; genetics ; Keratin-5 ; genetics ; Male ; Mutation ; Pedigree ; Sequence Analysis, DNA

Dystrophic epidermolysis bullosa (DEB) are caused by mutations in the COL7A1 gene, which encodes type VII collagen. Even though more than 500 different COL7A1 mutations have been identified in DEB, it still remains to be under-investigated. To investigate the mutation of COL7A1 in moderately severe phenotype of recessive DEB (RDEB) in a Korean patient, the mutation detection strategy was consisted of polymerase chain reaction (PCR) amplification of genomic DNA, followed by heteroduplex analysis, nucleotide sequencing of the PCR products demonstrating altered mobility. In this study, we found that one mutation (c.8569G>T) was detected within exon 116. The mutation of c.8569G>T in exon 116 changed the GAG (Glu) to TAG, eventually resulted in premature termination of type VII collagen polypeptide. Furthermore the mother did not have the mutation c.8569G>T in exon 116. The other novel mutation (c.4879G>A) was detected within exon 51 of both patient and mother, thereby resulting in changing valine (Val) to isoleucine (Ile) in type VII collagen polypeptide. Taken together, in this study we identified compound heterozygosity for COL7A1 mutations (c.8569G>T and c.4879G>A) in moderately severe RDEB in a Korean patient. We hope that this data contribute to the expanding database on COL7A1 mutations in DEB.
Adolescent ; Amino Acid Substitution ; Asian Continental Ancestry Group/*genetics ; Collagen Type VII/*genetics ; DNA Mutational Analysis ; Epidermolysis Bullosa Dystrophica/*genetics/pathology ; Heterozygote ; Humans ; Korea ; Male ; Pedigree ; Phenotype ; Point Mutation ; Polymerase Chain Reaction