Pseudohypoparathyroidism type 1B
Type of disease: Genetic, autosomal dominant | Rare conditions
Pseudohypoparathyroidism type 1B is a genetic disorder that resembles hypoparathyroidism (lowered levels of parathyroid hormone), but is caused by a lack of response to parathyroid hormone rather than having too little of the hormone itself. This condition is very similar to hypoparathyroidism, with low calcium levels and high phosphate levels in the blood. Type 1B involves resistance to PTH only in the kidneys. Affected individuals usually do not have an abnormal physical appearance and usually do not exhibit other endocrine abnormalities. This condition is inherited in an autosomal dominant pattern and is caused by a mutation in either the GNAS gene or STX16 gene. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.