Osteogenesis Imperfecta and Osteoporosis
Gene: ERO1A
ESHG 2026
3 individuals from 2 unrelated families (1 consanguineous) with homozygous variants in ERO1A ((p.His22Glnfs19) and p.(Gln154*)). They presented with ichthyosis (3), palmoplantar keratoderma (3), sparse eyebrows (2), fragile nails (2), microcephaly (2), low bone mineral density (1), and recurrent long bone fractures in early childhood (2). The variants segregated in the families.
Endoplasmic reticulum (ER) oxidoreductase 1α (ERO1A) oxidizes the protein disulfide isomerase (PDI) and promotes disulfide bond formation in newly synthesized polypeptides such as collagen I. The 3 patient-derived fibroblasts showed significantly reduced ERO1A mRNA levels, indicating nonsense-mediated mRNA decay. This was accompanied by absence of ERO1A protein and increased PDI levels. In whole-cell lysates from fibroblasts of 2 patients, collagen I was detected as a triple band, whereas only two bands were observed in control cells. They found disordered collagen I aggregates in the extracellular matrix of all patient-derived fibroblasts. As a possible compensatory response, mRNA and protein levels for the collagen-specific ER chaperone HSP47 were increased in patient cells.
Sources: OtherCreated: 18 Aug 2026, 10:39 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Ichthyosis, keratoderma and bone fragility
Gene: ero1a has been classified as Amber List (Moderate Evidence).
gene: ERO1A was added gene: ERO1A was added to Osteogenesis Imperfecta and Osteoporosis. Sources: Expert Review Amber,Other Mode of inheritance for gene: ERO1A was set to BIALLELIC, autosomal or pseudoautosomal Phenotypes for gene: ERO1A were set to Ichthyosis, keratoderma and bone fragility