SNP Shot: Genomic Insights

Kuskokwim syndrome is defined by joint contractures, which are deformities that limit the range of motion in the affected joints. This disorder is exclusively observed in Yup'ik Eskimos, an Alaska Native population residing in the Kuskokwim River Delta region of southwestern Alaska.

The knee, ankle, and elbow joints are most frequently affected by contractures in Kuskokwim syndrome. However, other joints, especially in the lower body, can also be involved. These contractures are generally present at birth, and their severity increases during childhood. After childhood, the contractures typically stabilize and persist throughout the individual's life.

Some individuals with Kuskokwim syndrome exhibit additional bone abnormalities, primarily affecting the spine, pelvis, and feet. These abnormalities can include an exaggerated inward curvature of the lower back (lordosis), lateral curvature of the spine (scoliosis), wedge-shaped vertebrae, or a clavicle (collarbone) abnormality referred to as clubbing. Individuals with Kuskokwim syndrome are usually shorter than their age-matched peers and may present with an unusually large head size (macrocephaly).

Inheritance:

Kuskokwim syndrome follows an autosomal recessive inheritance pattern. This means that for an individual to be affected, both copies of the responsible gene in each cell must carry a mutation. The parents of an individual with an autosomal recessive disorder each carry one copy of the mutated gene but usually do not exhibit any signs or symptoms of the condition themselves.