This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Pseudopseudohypoparathyroidism (PPHP) is an inherited condition that causes short stature, round face, and short hand bones. PPHP causes joints and other soft tissues in the body to harden. It also affects how bones are formed. As a result, PPHP can cause bone, joint, and nerve damage, and this damage can cause lasting pain. Some people with PPHP (10%) also have learning disability. PHPP is caused by mutations in the GNAS gene and is inherited in an autosomal dominant fashion. This condition is usually inherited from the father (genomic imprinting).
PPHP is genetically related to pseudohypoparathyroidism type Ia (PHP-1a). Signs and symptoms are similar, however people with PPHP do not show resistance to parathyroid hormone while people with PHP-1a do. Obesity is characteristic for PHP-1a and may be severe, while obesity is less prominent and may be absent among people with PPHP. Both PHP-1a and PPHP are caused by mutations that affect the function of the GNAS gene. But people who inherit the mutation from their mother develop PHP-1a; whereas those who inherit the mutation from their father develop PPHP.
For more information, visit GARD.