SNP Shot: Genomic Insights

PURA syndrome is a disorder marked by intellectual disability and delays in developmental milestones, particularly speech and motor skills like walking. Speech production and vocabulary (expressive language) are typically more impaired than the ability to understand language (receptive language). Many individuals with PURA syndrome are nonverbal. Walking may be significantly delayed, and some never achieve this milestone. Infants with PURA syndrome often present with low muscle tone (hypotonia), feeding challenges, and swallowing difficulties (dysphagia) that can persist throughout their lives. During infancy, they may also experience excessive sleepiness (hypersomnolence), low body temperature (hypothermia), and breathing irregularities such as pauses in breathing (apnea) or abnormally slow breathing (hypoventilation), which typically resolve after the first year of life.

Epilepsy, characterized by recurrent seizures, is frequently observed in PURA syndrome. Seizures usually manifest before the age of 5, often starting with uncontrolled muscle jerks (myoclonus). Other seizure types, like generalized tonic-clonic seizures (involving loss of consciousness, muscle stiffness, and convulsions), may also develop. Seizures in individuals with PURA syndrome can be challenging to manage.

Individuals with PURA syndrome may also exhibit a range of other features, including abnormalities affecting the heart, eyes, urogenital system, gastrointestinal system, and skeletal system. Hormonal imbalances may also occur, such as early puberty (precocious puberty) or vitamin D deficiency (low vitamin D levels).

Inheritance:

PURA syndrome follows an autosomal dominant inheritance pattern. This means that having only one copy of the altered gene in each cell is enough to cause the condition. Most cases arise from new (de novo) mutations in the gene, occurring either during the formation of eggs or sperm in a parent or during early embryonic development. Consequently, many individuals diagnosed with PURA syndrome have no family history of the disorder.