What causes Albright's hereditary osteodystrophy ?
What causes Albright's hereditary osteodystrophy? Albright's hereditary osteodystophy is caused by mutations in the GNAS gene. Albright's hereditary osteodystrophy is transmitted as an autosomal dominant trait. The hormone resistance associated with Albright's hereditary osteodystrophy, in particular resistance to parathyroid hormone, depends on whether the mutated allele comes from the father or the mother. Within a family, some patients have isolated features of Albright's hereditary osteodystrophy without hormone resistance (called pseudopseudohypoparathyroidism) and some show the complete clinical picture. This is due to parental imprinting of the GNAS gene. Thus, in individuals with a mutated maternal GNAS allele, the disease is fully expressed while in individuals with a mutated paternal allele the disease is partially expressed and hormone resistance is not present.