SNP Shot: Genomic Insights

Glutaric acidemia type I, also known as glutaric aciduria type I, is a genetic condition where the body struggles to process specific proteins. It's categorized as an organic acid disorder, meaning it causes a build-up of organic acids in the body. These abnormal levels in the blood (organic acidemia), urine (organic aciduria), and tissues can be harmful and lead to serious health issues.

Individuals with glutaric acidemia type I lack sufficient amounts of an enzyme needed to break down the amino acids lysine, hydroxylysine, and tryptophan, all of which are components of protein. This deficiency allows excessive levels of these amino acids and their byproducts to accumulate, potentially damaging the brain, especially the basal ganglia – areas responsible for controlling movement. Intellectual disability can also result.

The severity of glutaric acidemia type I differs greatly among individuals. Some experience only mild effects, while others suffer severe complications. Symptoms typically appear in infancy or early childhood, although a few individuals may not show signs until adolescence or adulthood.

Some infants with glutaric acidemia type I are born with an abnormally large head (macrocephaly). Affected individuals might experience movement difficulties such as spasms, jerking, rigidity, or reduced muscle tone. Bleeding in the brain or eyes has been observed in some cases, which could be misdiagnosed as child abuse. A carefully managed diet can help slow down neurological damage. Stress from infections, fever, or other physical demands can worsen symptoms, with only limited recovery.

Inheritance:

Glutaric acidemia type I follows an autosomal recessive inheritance pattern. This means that both copies of the responsible gene in each cell must have mutations for the condition to manifest. Individuals who inherit one copy of the mutated gene from each parent will develop the disorder. The parents, carrying only one copy of the mutated gene, are typically asymptomatic.