SNP Shot: Genomic Insights

Anauxetic dysplasia is a genetic condition resulting in dwarfism (extremely short stature) accompanied by several skeletal irregularities, excessive joint flexibility (hypermobility), dental issues, and characteristic facial features. Some individuals with this condition may also have mild intellectual disabilities.

Individuals affected by anauxetic dysplasia exhibit disproportionate dwarfism, meaning their limbs are shorter than expected for their overall height, starting before birth. Atlantoaxial subluxation, where the bones at the top of the spine become misaligned, can occur, leading to spinal cord compression. This compression can cause neurological problems like pain, tingling, numbness, impaired coordination, muscle weakness, and even paralysis. In severe instances, compression of the spinal cord can be life-threatening in young children due to paralysis of the breathing muscles.

Additional skeletal abnormalities associated with anauxetic dysplasia include a barrel chest and kyphoscoliosis (a rounded upper back that also curves to the side). If left uncorrected surgically, kyphoscoliosis can restrict lung function and cause breathing difficulties. Other possible skeletal features include hyperlordosis (an exaggerated curve of the lower back), hip dislocations, and rocker-bottom feet (soles that are rounded outward).

The characteristic facial appearance of individuals with anauxetic dysplasia often includes closely set eyes (hypotelorism), a flattened or sunken midface (midface hypoplasia), an unusually large tongue (macroglossia), and a prominent chin (prognathism). They may also have fewer teeth than normal (hypodontia).

Inheritance:

Anauxetic dysplasia is inherited through an autosomal recessive inheritance pattern. This means that a person must inherit two copies of the mutated gene, one from each parent, to develop the condition. The parents, who each carry only one copy of the mutated gene, are usually asymptomatic carriers.