Dictionary

glucose-6-phosphate dehydrogenase See G6PD.

glucosylceramidosis See Gaucher disease.

glucuronosyltransferase, UDP- A liver enzyme that is essential to the disposal of bilirubin. An abnormality of UDP-glucuronosyltransferase results in a condition called Gilbert syndrome. See also Gilbert syndrome.

gluteal Pertaining to the buttocks region, which is formed by the gluteus maximus, gluteus medius, and gluteus minimus muscles.

gluten A protein that is found in wheat and related grains. Gluten can be found in a large variety of processed foods, including soups, salad dressings, and natural flavorings. Unidentified starches, hydrolyzed proteins, and binders and fillers used in medications or vitamins can be unsuspected sources of gluten. People with celiac sprue, Crohn’s disease, or…

gluten enteropathy See celiac sprue.

glycemic index An indicator of the rapidity and extent to which carbohydrate-containing foods raise the blood glucose levels in the two hours after consumption. Foods containing carbohydrates that break down most quickly during digestion have the highest glycemic index. Also called the dietary glycemic index. See also glucose.

glycogen storage disease One of the multiple inherited disorders of metabolism that interfere with glycogen synthesis or breakdown, leading to the storage of carbohydrates as glycogen in the body. The conditions may affect the liver or the skeletal (striated) muscle, both primary glycogen storage sites. Symptoms and signs depend upon the exact type but can…

glycosaminoglycan A negatively charged chain of polysaccharides (modified sugars) that is composed of repeating disaccharide units. Abbreviated GAG. Important GAGs in the human body include chondroitin sulfate, dermatan sulfate, heparan sulfate, heparin, hyaluronate, and keratan sulfate. GAGs are involved as lubricants and components of bone, cartilage, blood vessels, and certain types of cells. Also known…

GM1-gangliosidosis A rare genetic lipid storage disorder that is similar to Hurler syndrome and TaySachs disease but that affects both the brain and the viscera. Symptoms include skeletal deformities and severe effects on the brain and organs. The mutation that is responsible for the disease is located on chromosome 3. There is no treatment for…

gland, tarsal See gland, Meibomian.

gland, thyroid A gland that makes and stores hormones that help regulate heart rate, blood pressure, body temperature, and the conversion of food to energy (metabolism). Thyroid hormones are also essential for proper growth and development. The thyroid gland is located in the lower part of the neck, below the Adam’s apple, wrapped around the…