Albright hereditary osteodystrophy (AHO) describes a constellation of clinical manifestations, seen in certain forms of pseudohypoparathyroidism (PHP; see this term) and other types of hormone resistance, consisting of short stature, rounded face, subcutaneous ossifications, brachydactyly and variable degrees of developmental delay.
The prevalence is unknown.
AHO describes the combination of the following clinical characteristics: brachydactyly (most often the shortening of the 3, 4 and 5th metacarpals), rounded face, short stature (mean final height is -2 to -3 SD), central obesity, subcutaneous ossifications and variable degrees of developmental delay. Intellectual disability is sometimes observed. These somatic features are associated with resistance to parathyroid hormone (PTH) and to other hormones; in particular thyroid-stimulating hormone (TSH) in pseudohypoparathyroidism type 1a and 1c (see these terms). Patients with only the physical features of AHO but no PTH resistance are said to have pseudopseudohypoparathyroidism (PPHP; see this term).
In families where PHP is present, AHO is mostly due to heterozygous inactivating mutations of the GNAS gene (20q13.2-q13.3). This gene encodes the alpha-subunit of Gs, the heterotrimeric G protein that couples with heptahelical plasma membrane receptors. The parental origin of the mutation determines whether the patient will exhibit resistance to hormones (maternal inheritance) or not (paternal inheritance). AHO may also present as an isolated syndrome (originally termed AHO-like syndrome, now termed 2q37 microdeletion syndrome; see this term) and in this case it is associated with small deletions of chromosome 2.
AHO, when found in PHP1a, PHP1c and PPHP, is inherited autosomal dominantly and genetic counseling is possible.
Last update: October 2014