Infantile systemic hyalinosis in an I ranian family with a mutation in the CMG 2/ ANTXR 2 gene

Summary Infantile systemic hyalinosis ( ISH ) is an extremely rare genodermatosis, characterized by thickened skin, joint contractures and subcutaneous nodules. ISH is caused by mutations in the CMG 2 gene, which encodes a protein of unknown function. In this report, we describe a patient with ISH , who was a twin born to a consanguineous Iranian couple, and who demonstrated unusual skin findings in addition to the characteristic features of ISH . Mutation analysis disclosed a homozygous deletion mutation, c.1074delT in CMG 2 , resulting in a frameshift and premature termination codon 50 amino acids downstream of the deletion. This information adds to the recurring nature of this mutation in ISH , with implications for genetic counselling in extended families with a history of this disease.