Klausegger Alfred, Leditzky Fabian, Krämer Susanne, Palisson Francis, Yubero María Joao, Véliz Sebastián, Koh Mark Jean Aan, Tan Ene-Choo, Laimer Martin, Bauer Johann Wolfgang, Fuentes Ignacia
EB House Austria, Department of Dermatology and Allergology, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria.
Special Care Clinic, Universidad de Chile, Olivos 943, Independencia, Santiago 8380544, Chile.
Int J Mol Sci. 2025 Apr 29;26(9):4237. doi: 10.3390/ijms26094237.
Kindler Epidermolysis bullosa (KEB; OMIM 173650) is a rare autosomal recessive genodermatosis characterized by bullous poikiloderma and photosensitivity. Additional presentations include blistering, poor wound healing, skin atrophy, and increased risk of skin cancer. Most cases of KEB result from aberrations in the (Fermitin family member 1) gene encoding kindlin-1 and include nonsense, frameshift, splicing, and missense variants. Large deletion variants have been reported in nine cases to date. Most variants are predicted to lead to premature termination of translation and to loss of kindlin-1 function. In this study, we report on a 33-year-old male patient who presented with typical clinical manifestations of KEB. As routine molecular testing failed to obtain a diagnosis, Next Generation Sequencing (NGS) of an Epidermolysis Bullosa (EB)-specific panel was carried out followed by the determination of the deletion breakpoints and verification at the mRNA and protein levels. This approach revealed a new large homozygous deletion of ~9.4 kb in the gene involving exons 7 to 9. Finally, we performed a literature review on large deletions. The deletion is predicted to skip exons 7 to 9 within the mRNA, which results in a frameshift. The patient's phenotype is likely caused by the resulting truncated and non-functioning protein. Our report further enriches the spectrum of gene variants to improve genotype-phenotype correlations.
金德勒大疱性表皮松解症(KEB;OMIM 173650)是一种罕见的常染色体隐性遗传性皮肤病,其特征为大疱性皮肤异色症和光敏性。其他表现包括水疱形成、伤口愈合不良、皮肤萎缩以及皮肤癌风险增加。大多数KEB病例是由编码整合素结合蛋白1的FERMT1(黏着斑蛋白家族成员1)基因异常引起的,包括无义、移码、剪接和错义变异。迄今为止,已报道9例大缺失变异。大多数变异预计会导致翻译提前终止并丧失整合素结合蛋白1的功能。在本研究中,我们报告了一名33岁男性患者,其表现出KEB的典型临床表现。由于常规分子检测未能得出诊断结果,因此对大疱性表皮松解症(EB)特异性基因 panel 进行了二代测序(NGS),随后确定缺失断点并在 mRNA 和蛋白质水平进行验证。这种方法揭示了FERMT1基因中一个新的约9.4 kb的大纯合缺失,涉及外显子7至9。最后,我们对FERMT1基因的大缺失进行了文献综述。该缺失预计会导致mRNA中外显子7至9跳跃,从而导致移码。患者的表型可能是由产生的截短且无功能的蛋白质引起的。我们的报告进一步丰富了FERMT1基因变异谱,以改善基因型与表型的相关性。