SNP Shot: Genomic Insights

Generalized arterial calcification of infancy (GACI) is a circulatory system disease that manifests either before birth or in early infancy. Its hallmark is the abnormal buildup of calcium deposits (calcification) in the arterial walls, specifically those arteries carrying blood away from the heart. This calcification is frequently accompanied by thickening of the inner layer (intima) of these arterial walls. These changes cause the arteries to narrow (stenosis) and become rigid, forcing the heart to pump harder. Consequently, individuals with GACI may develop heart failure, exhibiting symptoms like breathing difficulties, swelling (edema) in the limbs, a bluish discoloration of the skin or lips (cyanosis), severe high blood pressure (hypertension), and an enlarged heart (cardiomegaly).

Beyond the arteries, individuals with GACI may also experience calcification in other organs and tissues, especially around the joints. Furthermore, hearing loss or bone softening and weakening (rickets) can occur.

Some individuals with GACI display features resembling those found in pseudoxanthoma elasticum (PXE). PXE involves the build-up of calcium and other minerals (mineralization) in elastic fibers, components of connective tissue. Connective tissue provides structural support and flexibility throughout the body. Overlapping features between PXE and GACI include yellowish bumps (papules) in skin folds like the underarms, and eye abnormalities known as angioid streaks, detectable during an eye exam.

Due to the severe cardiovascular complications associated with GACI, many affected individuals do not survive beyond infancy, often succumbing to a heart attack or stroke. However, those who survive the first six months, considered a critical period, can potentially live into adolescence or early adulthood.

Inheritance:

GACI is inherited in an autosomal recessive manner. This means that an affected individual must inherit a mutated copy of the relevant gene from each parent. The parents, while carriers of one copy of the mutated gene, typically do not exhibit any signs or symptoms of the condition themselves.