SNP Shot: Genomic Insights

Lipoid proteinosis is a rare disorder characterized by the accumulation of small deposits of proteins and other substances in various tissues throughout the body. These deposits commonly affect the skin, the lining of the respiratory tract, and mucous membranes such as those in the eyelids and mouth.

Often, the first noticeable symptom is a hoarse voice, resulting from deposits on the vocal cords. In infants, this manifests as a weak cry. Voice changes are typically lifelong and can progress to difficulty speaking or complete loss of voice. When the throat, tonsils, and lips are affected, breathing problems and upper respiratory infections can occur. Deposits in the tongue may cause it to become thick and shortened. Thickening of the frenulum, the tissue connecting the tongue to the floor of the mouth, can also limit tongue movement. Additionally, the tongue's surface may appear smooth due to damage to the taste buds.

A hallmark of lipoid proteinosis is the presence of tiny, bead-like bumps along the lash line of both upper and lower eyelids, a condition known as moniliform blepharosis. These bumps may cause irritation or itching but generally do not affect vision.

In children with lipoid proteinosis, the skin and mucous membranes are often fragile, leading to easy bleeding and scabbing after minor injuries. These issues often appear first in infancy, affecting the mouth, face, and limbs. Over time, scabs can turn into blisters and scars. Deposits accumulate within the skin, causing it to thicken and take on a yellowish hue. Skin damage is more common in areas subject to friction, such as the hands, elbows, knees, buttocks, and armpits. Some individuals may experience hair loss (alopecia) affecting the scalp, eyelashes, and eyebrows.

Neurological symptoms are also frequently observed in individuals with lipoid proteinosis. These can include recurrent seizures (epilepsy), behavioral problems, and neurological issues such as headaches, aggression, paranoia, hallucinations, short-term memory loss, and a lack of fear. These neurological manifestations are believed to be linked to deposits and calcium buildup (calcification) in the temporal lobes of the brain, which are involved in processing hearing, speech, memory, and emotions. However, the precise cause of these neurological features remains unclear, as brain abnormalities and neurological symptoms do not always occur together.

Deposits may also be found in internal organs such as the stomach, duodenum (a part of the small intestine), and colon. In many cases, these deposits do not cause any symptoms and may disappear over time.

Inheritance:

Lipoid proteinosis is an autosomal recessive disorder. This means that an individual must inherit two copies of the mutated gene, one from each parent, to develop the condition. The parents, who each carry one copy of the mutated gene, are typically unaffected carriers and do not exhibit symptoms of the condition.