SNP Shot: Genomic Insights

Cantú syndrome is a rare disorder characterized by excessive hair (hypertrichosis), a characteristic facial appearance, cardiac anomalies, and various other irregularities. The specific manifestations of the condition differ from person to person.

Individuals with Cantú syndrome typically have thick hair on their scalp that extends down the forehead and onto the cheeks near the ears. They also exhibit increased body hair, particularly on the back, arms, and legs. A large head size (macrocephaly) and distinctive, often described as "coarse," facial features are common. These features include a wide nasal bridge, epicanthal folds (skin folds covering the inner corners of the eyes), and a wide mouth with full lips. With age, the face tends to lengthen, the chin becomes more pronounced, and the eyes appear more deep-set.

Many newborns with Cantú syndrome present with heart defects such as an enlarged heart (cardiomegaly) or patent ductus arteriosus (PDA). The ductus arteriosus is a connection between the aorta and pulmonary artery that is present during fetal development. It usually closes shortly after birth, but remains open (patent) in infants with PDA. Other heart problems observed in individuals with Cantú syndrome include pericardial effusion (fluid buildup around the heart) and pulmonary hypertension (high blood pressure in the vessels carrying blood from the heart to the lungs).

Further characteristics of Cantú syndrome include unusual skeletal abnormalities, a large birth size (macrosomia), reduced subcutaneous fat (fat under the skin) starting in childhood, prominent horizontal creases on the palms and soles, and increased vulnerability to respiratory infections. Other reported signs and symptoms are lymphedema (abnormal tissue swelling), scoliosis (side-to-side spinal curvature), and osteopenia (reduced bone density). Some affected children experience hypotonia (weak muscle tone), which can delay the development of motor skills like sitting, standing, and walking. Most exhibit mild speech delays, and some may have mild intellectual disabilities or learning difficulties.

Inheritance:

Cantú syndrome follows an autosomal dominant inheritance pattern. This means that only one copy of a mutated ABCC9 gene in each cell is needed to cause the disorder. In most instances, the syndrome arises from new gene mutations in individuals with no family history of the condition. Rarely, an affected individual inherits the mutation from a parent who also has the syndrome.