SNP Shot: Genomic Insights

Coffin-Siris syndrome is a disorder impacting multiple areas of the body. It is characterized by a variety of signs and symptoms, but key features include developmental delays or intellectual disability, abnormalities of the pinky fingers or toes, and distinctive facial characteristics.

Individuals with Coffin-Siris syndrome commonly experience mild to severe intellectual disability or delays in speech and motor skill development, such as learning to sit and walk. Another common characteristic is the underdevelopment (hypoplasia) of the fingertips or toes, or underdeveloped or missing nails. These issues are most frequently observed on the fifth fingers or toes.

Furthermore, many individuals with Coffin-Siris syndrome exhibit what are described as "coarse" facial features. These often include a wide nose with a flattened nasal bridge, a wide mouth with full lips, and prominent eyebrows and eyelashes. Increased hair growth (hirsutism) may be present on other areas of the face and body, while the hair on the scalp is often thin. The facial features associated with Coffin-Siris syndrome can vary, and not everyone affected will have all of the typical characteristics. Some may also have an unusually small head size (microcephaly).

In addition, some babies and children with Coffin-Siris syndrome may experience recurring respiratory infections, feeding difficulties, and struggle to gain weight properly (failure to thrive). Other possible signs and symptoms include short stature, reduced muscle tone (hypotonia), and overly flexible (lax) joints. Abnormalities involving the eyes, brain, heart, and kidneys can also occur.

Inheritance:

Coffin-Siris syndrome is typically inherited in an autosomal dominant manner, meaning that only one copy of the mutated gene in each cell is enough to cause the condition. However, it's rare for the syndrome to be passed down from a parent with the condition. Instead, it usually arises from new (de novo) changes in the gene, which are most likely to occur during the early stages of embryonic development.