Category: Ae-Ag

A condition in which the gallbladder fails to develop. It occurs in 1 in about every 1,000 people, usually without additional birth defects.

A congenital abnormality (a birth defect) in which there is partial or complete absence (agenesis) of the corpus callosum, the area of the brain which connects the two cerebral hemispheres (the two halves of the brain). Agenesis of the corpus callosum can occur as a severe syndrome in infancy or childhood, as a milder condition…

Lack of development. For example, agenesis of a toe means the toe failed to form.

An agency of the U.S. Department of Health and Human Services under the Public Health Service that works with states and other federal agencies to prevent exposure to hazardous substances from waste sites. The agency conducts public health assessments, health studies, surveillance activities, and health education training in communities around waste sites on the U.S.…

An eye disease with its onset usually after age 60 that can progressively destroy the macula, the central portion of the retina, impairing central vision. Age-related macular degeneration (AMD or ARMD) rarely causes blindness because only the center of vision is affected. However, injury to the macula in the center of the retina can impair the ability to see straight…

Age-related hearing loss with gradually progressive inability to hear, especially high frequency sounds. Presbycusis most often occurs in both ears, although not necessarily at the same time or rate. Because the loss of hearing is so gradual, people with presbycusis may not realize that their hearing is diminishing. They may have trouble distinguishing and understanding conversation in a noisy…

 The age of the father at the time he conceives a child. Advanced paternal age is associated with an increased risk of certain genetic mutations, a risk that rises linearly with the age of the father. 

The age of the mother at the time of delivery. Advanced maternal age is usually defined as age 35 or more at delivery. Advanced maternal age predisposes to Down syndrome (trisomy 21). The risk of having a Down syndrome baby rises with maternal age. It essentially doubles from 1 in 725 at maternal age 32 to 1 in 365…

A term designating someone’s age by decade. For example, a septuagenarian refers to someone in his or her seventies (age 70 to 79). The prefix in such terms is always from the Latin. For example, the Latin septuageni = seventy. Denarian: Someone age 10 to 19. Vicenarian: Someone in his or her twenties. Tricenarian: Someone…

Total or near-total absence of infection-fighting antibodies belonging to the class called gamma globulins. Agammaglobulinemia can be due to certain genetic diseases or caused by acquired diseases, including AIDS.