SNP Shot: Genomic Insights

Trichohepatoenteric syndrome (THES) is a disorder that impacts multiple areas of the body, notably the hair (tricho-), liver (hepato-), and intestines (enteric). A key characteristic of this condition is persistent and challenging diarrhea, leading to its alternative name, syndromic diarrhea. Infants with THES typically develop frequent, watery diarrhea within weeks of birth. Despite intravenous nutritional support (parenteral nutrition), many struggle to thrive, failing to gain weight or grow at the expected pace. Furthermore, most children with THES are born smaller than average and remain shorter than their peers throughout their lives.

Hair abnormalities are another hallmark of THES. The hair of affected individuals is often described as wooly, fragile, sparse, and easily detached. Microscopic examination may reveal variations in hair strand diameter, with areas of differing thickness, a characteristic known as trichorrhexis nodosa.

Additional signs and symptoms of THES can encompass liver problems, skin issues, and distinct facial characteristics. These facial features may include a broad forehead, a wide nasal base, and widely spaced eyes, often described as giving a "coarse" appearance. Many individuals with THES also exhibit immune system dysfunction, increasing their susceptibility to infections. Less frequently, THES is linked to heart (cardiac) defects. Mild intellectual disability has been observed in at least half of the children diagnosed with this condition.

THES can be life-threatening, particularly during childhood, especially if liver disease or severe infections develop.

Inheritance:

THES follows an autosomal recessive inheritance pattern. This means that an individual must inherit a mutated copy of the responsible gene from each parent. While both parents carry one copy of the mutated gene, they usually do not exhibit any signs or symptoms of the condition themselves.