Diseases of mineral metabolism such as familial multiple endocrine neoplasia type 1 (FMEN1), familial hypocaliuric hypercalcemia (FHH), familial hyperparathyroidism (FH), and pseudohypoparathyroidism (PHP) are known as hereditary abnormalities. Meaning these conditions are passed from parents to their children through genes. These specific conditions result in abnormal levels of calcium in the blood.

This study was designed to help researchers understand more about the genes that are responsible for these disorders. By learning more about the genetic process involved in hereditary abnormalities, new tests and treatments can be developed.

Subjects for this study will be members of families that have had relatives diagnosed with a disease of mineral metabolism. Participants will be asked to give blood samples for DNA extraction. DNA is the part of cells that carries genetic information.

The DNA will be analyzed and the results given to the subjects. Genetic counseling will be provided to subjects to aid in interpreting their results....

Familial multiple endocrine neoplasia type 1 (MEN1), familial hypocalciuric (or familial benign) hypercalcemia (FHH), hyperparathyroidism - jaw tumor syndrome (HPT-JT), other causes of familial isolated hyperparathyroidism (FIHP), and pseudohypoparathyroidism (PHP) are disorders of metabolism that are generally inherited in an autosomal dominant fashion. MEN1 is characterized by overgrowth and hyperfunction of the parathyroids, anterior pituitary and gastrointestinal endocrine tissue. MEN1, p15, p18, p21, and p27 are identified genes for MEN1- like states. FHH is characterized by a usually benign syndrome sometimes mistaken for typical primary hyperparathyroidism, which may result in unnecessary and unsuccessful parathyroid surgery. The CASR gene for the calcium-sensing receptor of the parathyroid cell is mutated in most FHH kindreds; a minority of kindreds with FHH have mutation of the GNA11 or AP2S1 gene. HPT-JT is a distinctive subtype of familial isolated hyperparathyroidism that has combinations of parathyroid adenoma, parathyroid cancer, jaw tumor, uterus tumor, kidney tumor and kidney cysts. It is caused by mutation of the CDC73/HRPT2 gene. PHP is characterized by parathyroid hormone resistance, and one form is associated with mutations in the gene encoding the alpha subunit of the stimulatory G protein. We are continuing to collect blood and tissue samples from affected and unaffected members of kindreds with known or suspected MEN1, FHH, HPT-JT, FIHP, PHP, and related disorders for the purpose of geneticanalysis and gene identification. In most cases, the procurement of specimens under this protocol will be at an off-site location. Samples will be processed for extraction of DNA and RNA.

• ELIGIBILITY CRITERIA:

  1. Patient has possible form of familial hyperparathyroidism. Or case is a clinically unaffected first degree relative of such a patient.
  2. The lower age limit to enter a clinically affected minor into the study is >= 4 years old. However, asymptomatic and possibly unaffected cases will not be enrolled, and blood will not be drawn, before age 5 years in MEN1, MEN1-like, HPT-JT, or FIHP kindreds or before age 10 in FHH kindreds.

Subjects for this study will be members of families that have had relatives diagnosed with a disease of mineral metabolism. Participants will be asked to give blood samples for DNA extraction. DNA is the part of cells that carries genetic information. The DNA will be analyzed and the results given to the subjects. Genetic counseling will be provided to subjects to aid in interpreting their results.