Group B Cockayne syndrome is a rare genetic disorder that belongs to a heterogeneous group of autosomal recessive disorders known as Cockayne syndrome (CS). It is characterized by the triad of growth retardation, neurological abnormalities, and sensitivity to sunlight. Group B CS is distinguished from other types of CS by the lack of a specific DNA repair defect.
Individuals affected by Group B CS typically experience a failure to thrive, resulting in short stature and underdevelopment of bones, muscles, and organs. They also present with various neurological abnormalities, including progressive intellectual disability, delayed development, and seizures. Moreover, patients may exhibit abnormalities in muscle tone and movement, such as poor coordination and a shuffling gait.
One of the hallmark features of Group B CS is extreme sensitivity to sunlight, resulting in severe sunburns, rashes, and blistering even with limited sun exposure. This sensitivity occurs due to impaired ability to repair UV light-induced DNA damage, leading to increased susceptibility to skin cancer. Other common symptoms include premature aging, hearing loss, dental abnormalities, and visual impairment.
The diagnosis of Group B CS is based on clinical manifestations, including physical and neurological characteristics, along with the absence of specific DNA repair defects linked to other types of CS. Genetic testing can be conducted to confirm the diagnosis by identifying mutations in the genes associated with Group B CS.
Currently, there is no cure for Group B Cockayne syndrome, and management primarily involves addressing the symptoms and providing supportive care.
