TY - JOUR
T1 - Identification of the first dominant mutation of LAMA5 gene causing a complex multisystem syndrome due to dysfunction of the extracellular matrix
AU - Sampaolo, Simone
AU - Napolitano, Filomena
AU - Tirozzi, Alfonsina
AU - Reccia, Mafalda Giovanna
AU - Lombardi, Luca
AU - Farina, Olimpia
AU - Barra, Adriano
AU - Cirillo, Ferdinando
AU - Melone, Mariarosa Anna Beatrice
AU - Gianfrancesco, Fernando
AU - Iorio, Giuseppe Di
AU - Esposito, Teresa
N1 - © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
PY - 2017/10
Y1 - 2017/10
N2 - BACKGROUND: The laminin alpha 5 gene (LAMA5) plays a master role in the maintenance and function of the extracellular matrix (ECM) in mammalian tissues, which is critical in developmental patterning, stem cell niches, cancer and genetic diseases. Its mutations have never been reported in human disease so far. The aim of this study was to associate the first mutation in LAMA5 gene to a novel multisystem syndrome.METHODS: A detailed characterisation of a three-generation family, including clinical, biochemical, instrumental and morphological analysis, together with genetics and expression (WES and RNAseq) studies, was performed.RESULTS: The heterozygous LAMA5 mutation c.9418G>A (p.V3140M) was associated with skin anomalies, impaired scarring, night blindness, muscle weakness, osteoarthritis, joint and internal organs ligaments laxity, malabsorption syndrome and hypothyroidism. We demonstrated that the mutation alters the amount of LAMA5 peptides likely derived from protein cleavage and perturbs the activation of the epithelial-mesenchymal signalling, producing an unbalanced expression of Sonic hedgehog and GLI1, which are upregulated in cells from affected individuals, and of ECM proteins (COL1A1, MMP1 and MMP3), which are strongly inhibited. Studies carried out using human skin biopsies showed alteration of dermal papilla with a reduction of the germinative layer and an early arrest of hair follicle downgrowth. The knock-in mouse model, generated in our laboratory, shows similar changes in the tissues studied so far.CONCLUSIONS: This is the first report of a disease phenotype associated with LAMA5 mutation in humans.
AB - BACKGROUND: The laminin alpha 5 gene (LAMA5) plays a master role in the maintenance and function of the extracellular matrix (ECM) in mammalian tissues, which is critical in developmental patterning, stem cell niches, cancer and genetic diseases. Its mutations have never been reported in human disease so far. The aim of this study was to associate the first mutation in LAMA5 gene to a novel multisystem syndrome.METHODS: A detailed characterisation of a three-generation family, including clinical, biochemical, instrumental and morphological analysis, together with genetics and expression (WES and RNAseq) studies, was performed.RESULTS: The heterozygous LAMA5 mutation c.9418G>A (p.V3140M) was associated with skin anomalies, impaired scarring, night blindness, muscle weakness, osteoarthritis, joint and internal organs ligaments laxity, malabsorption syndrome and hypothyroidism. We demonstrated that the mutation alters the amount of LAMA5 peptides likely derived from protein cleavage and perturbs the activation of the epithelial-mesenchymal signalling, producing an unbalanced expression of Sonic hedgehog and GLI1, which are upregulated in cells from affected individuals, and of ECM proteins (COL1A1, MMP1 and MMP3), which are strongly inhibited. Studies carried out using human skin biopsies showed alteration of dermal papilla with a reduction of the germinative layer and an early arrest of hair follicle downgrowth. The knock-in mouse model, generated in our laboratory, shows similar changes in the tissues studied so far.CONCLUSIONS: This is the first report of a disease phenotype associated with LAMA5 mutation in humans.
KW - Journal Article
U2 - 10.1136/jmedgenet-2017-104555
DO - 10.1136/jmedgenet-2017-104555
M3 - Article
C2 - 28735299
VL - 54
SP - 710
EP - 720
JO - Journal of Medical Genetics
JF - Journal of Medical Genetics
SN - 0022-2593
IS - 10
ER -