What do you mean by Hutchinson–Gilford progeria?

Hutchinson–Gilford Progeria Syndrome (HGPS) is a very rare genetic disorder in children, where the body ages much faster than normal. The word "progeria" comes from Greek, where "pro" means "before" and "geras" means "old age." This disease was first explained by Dr. Jonathan Hutchinson in 1886 and later by Dr. Hastings Gilford in 1897, which is why it is called Hutchinson–Gilford progeria. It is caused by a mutation in the LMNA gene, which gives instructions to make a protein called lamin A. This protein supports the structure of the nucleus in cells. In HGPS, the mutation forms an abnormal protein called progerin, which weakens the nuclear envelope, leading to faster cell damage and aging. The mutation is usually not inherited, meaning the parents are normal and the change happens suddenly during early development.

[Note- LMNA Gene: The LMNA gene is responsible for producing Lamin A and Lamin C proteins, which are crucial for maintaining the structural integrity of the nucleus. It is located on chromosome 1 (specifically at 1q21.2).]

Cause of the Disease:

HGPS is caused by a mutation in the LMNA gene present on chromosome 1. This gene makes lamin A, a protein that maintains the shape and stability of the nucleus. Due to the mutation, a defective protein called progerin is produced. Progerin gets stuck in the nuclear membrane and causes the nucleus to become abnormal in shape. This affects the function of the cell and leads to early aging of the body.

Symptoms:

The symptoms of HGPS start appearing within the first 1 to 2 years of life. Children appear normal at birth but then start showing early signs of aging such as:
  • Growth failure and short height
  • Loss of hair (alopecia)
  • Thin skin with visible veins
  • A small face with a pointed nose and small jaw
  • Stiff joints and weak bones
  • Loss of body fat and muscles
  • Aged facial appearance
  • Hardening of arteries (atherosclerosis), leading to heart problems
  • Importantly, the mental development of affected children remains normal.

Diagnosis:

HGPS is usually suspected by physical symptoms. The final confirmation is done through genetic testing, especially testing the LMNA gene to detect the specific mutation responsible for producing progerin.

Treatment:

There is no permanent cure for progeria, but treatments can help improve quality of life. A drug called lonafarnib, which is a farnesyltransferase inhibitor, has been approved and shows benefits in slowing disease progression. Other supportive treatments include:
  • Medications for heart problems
  • Physical therapy
  • Healthy, high-energy diet
  • Regular monitoring of cardiovascular health






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