SNP Shot: Genomic Insights

Roberts syndrome is a genetic condition marked by deformities of the limbs and face. Individuals with this syndrome experience slow growth both before and after they are born. About half of all individuals with Roberts syndrome have some degree of intellectual disability, ranging from mild to severe.

Children born with Roberts syndrome exhibit abnormalities in all four limbs. These include shortened arm and leg bones (hypomelia), particularly affecting the forearm and lower leg bones. In severe instances, the limbs can be extremely short, causing the hands and feet to be positioned very close to the body (phocomelia). People with Roberts syndrome may also have missing or abnormal fingers and toes, and joint contractures are frequently observed at the elbows and knees. Limb abnormalities tend to be very symmetrical on both sides of the body, although the arms are usually more severely affected than the legs.

Individuals with Roberts syndrome commonly present with various facial abnormalities, such as a cleft lip (with or without a cleft palate), a small chin (micrognathia), ear malformations, widely spaced eyes (hypertelorism), eyes that slant downwards (down-slanting palpebral fissures), small nostrils, and a distinctive beaked nose. They may also have a small head size (microcephaly) or clouding of the cornea (corneal opacities). In severe cases, a sac-like protrusion of the brain (encephalocele) can occur on the front of the head. Additionally, individuals with Roberts syndrome may have abnormalities affecting the heart, kidneys, and genitals.

Infants with a severe form of Roberts syndrome often do not survive to birth or die shortly thereafter. Individuals with milder forms may live into adulthood. SC phocomelia syndrome was initially considered a separate condition, but it is now recognized as a milder form of Roberts syndrome. The abbreviation "SC" comes from the first letters of the last names of the first two families diagnosed with this variation.

Inheritance:

The inheritance pattern of this condition is autosomal recessive. This means that both copies of the responsible gene in each cell must have a mutation for the condition to manifest. The parents of an individual with an autosomal recessive disorder each carry one copy of the mutated gene, but they typically do not exhibit any signs or symptoms of the condition themselves.