What Is Progeria? Understanding Rare Genetic Disorder That Causes Children to Age Prematurely

Biology defines aging as the time-related deterioration of the physiological functions needed for survival and reproduction. In humans, aging is a gradual, continuous process that starts in early adulthood, with most bodily functions beginning to decline in early middle age. However, there is a rare condition called progeria, where aging happens quickly in children.

What is Progeria?

Progeria is a progressive genetic disorder that causes children to age rapidly. This condition gets its name from the Greek word "geras," which means "old age." It is also known as Hutchinson-Gilford progeria syndrome (HGPS), after Dr. Jonathan Hutchinson and Dr. Hastings Gilford who originally described the disease in the late 1800s.

Children with progeria appear healthy at birth, but they usually begin to show signs of premature aging during their first one to two years of life. One year after birth, symptoms like loss of hair and loss of fat tissue begin to appear. They also grow slowly, and they do not gain weight as expected.

While children with the condition have typical intelligence, their rapid aging causes some distinct physical characteristics. These include having prominent eyes, tough and wrinkled skin, a beaked nose, and a disproportionately small face compared to head size.

Meanwhile, the disease also comes with craniofacial abnormalities that may include a large open soft spot on the head, delayed teeth eruption, and underdeveloped jaw. As progeria advances, it leads to the development of less obvious symptoms like hip dislocation, cataracts, and arthritis.

Progeria is always fatal, and the average life expectancy for a child with this disease is about 14.5 years. Some may die younger, while others may live longer up to 20 years.

Most children with progeria die of heart problems such as severe atherosclerosis. This same heart disease affects millions of aging adults but at a much younger age. Atherosclerosis happens due to plaque buildup within the walls of the arteries, making them less elastic and stiffer. Complications from this disease can lead to heart attack or even stroke.

Progeria is extremely rare, occurring only in one of every four million live births worldwide. About 400 children and young adults around the globe currently live with this condition.

What Causes Progeria?

Progeria is caused by the genetic mutation in the LMNA gene, the one responsible for the production of a protein called lamin A. This protein is vital for structural scaffolding, which holds together the nucleus of each cell in the body.

A slight mutation in the LMNA gene leads to the creation of an irregular form of the lamin A protein known as progerin. When progerin is formed, it takes the place of the lamin A, making the nuclei of cells unstable. The damage causes early death of every cell in the body, leading to premature aging.

Nearly all cases of progeria happen as a new, spontaneous mutation in the LMNA gene. This means that the disease is not affected by the biological history of the family. In short, progeria is not inherited from a parent, since mutation almost always occurs in the sperm cell before conception.

Progeria is also found to be an autosomal dominant disorder. This means that one copy of the mutated gene in each cell is enough to cause this genetic disorder.