Review of published reports of Albright's hereditary osteodystrophy (AHO) involving two or more generations shows a marked excess of maternal transmission. Full expression of the gene (AHO + hormone resistance, pseudohypoparathyroidism) occurs in maternally transmitted cases and partial expression (AHO alone) when the gene is inherited from the father, suggesting the involvement of genomic imprinting in the expression of this disorder.