The TANC2 gene provides instructions for creating a protein known as Tetratricopeptide Repeat, Ankyrin Repeat And Coiled-Coil Containing 2. This gene plays a role in brain function, helping to control the intricate connections between brain cells. When changes occur in this gene, its normal operation can be disrupted, which may lead to various health implications, particularly affecting neurodevelopment.
TANC2’s Normal Role
The TANC2 gene produces the TANC2 protein, a large multi-domain protein primarily found in the brain. This protein is concentrated at postsynaptic densities, which are specialized areas on neurons that receive signals from other neurons. At these sites, TANC2 acts as a scaffolding protein, meaning it helps organize and stabilize other proteins involved in communication between brain cells, known as synapses.
The proper functioning of TANC2 is important for synaptic plasticity, which is the ability of synapses to strengthen or weaken over time in response to activity. This process is fundamental for learning and memory. TANC2 also interacts with and influences signaling pathways, such as the mTOR pathway, which is involved in cell growth, proliferation, and survival in neurons. Its presence at both synaptic and non-synaptic sites indicates its broader involvement in neuronal functions and overall brain development.
How TANC2 Gene Changes Affect Health
Variations or changes in the TANC2 gene can disrupt the normal function of the TANC2 protein, leading to a spectrum of neurodevelopmental conditions. These changes can result in abnormally shaped proteins that hinder nerve cells from responding properly to signals, causing the associated symptoms. Such conditions are collectively referred to as TANC2-related disorders.
Most individuals with TANC2 gene changes experience developmental delays and intellectual disability (about 96%). Speech delay is also a common characteristic, affecting approximately 91% of individuals. Features of autism spectrum disorder are often observed, along with other behavioral issues such as attention-deficit/hyperactivity disorder (ADHD), aggression, repetitive behaviors, and anxiety.
The impact of TANC2 gene changes can vary widely among individuals, demonstrating what is known as variable expressivity. Some individuals may experience seizures, while others might exhibit motor development delays, uncoordinated movements, or chronic constipation. Skeletal anomalies, including relaxed joints, spinal column defects like scoliosis, and foot or chest defects, have also been noted.
Identifying TANC2-Related Conditions
Identifying TANC2-related conditions begins when a healthcare professional observes certain signs or symptoms in an individual. Significant developmental delays, particularly in speech and motor skills, along with specific behavioral patterns such as those seen in autism spectrum disorder, can prompt further investigation. A thorough medical history and physical examination are the first steps in this process.
To confirm a diagnosis, genetic testing is used to detect changes in the TANC2 gene. Whole exome sequencing or gene panel testing are common methods employed for this purpose. The TANC2 gene is specifically located on chromosome 2q24.3. In many cases, TANC2-related syndrome results from a “de novo” genetic variant, meaning it is a new change not inherited from either parent.
Supporting Individuals with TANC2 Gene Changes
Supporting individuals diagnosed with TANC2 gene changes involves a comprehensive and individualized approach focused on managing symptoms and enhancing their development. While there are currently no specific medications designed to treat the underlying genetic condition, various therapies aim to address the diverse range of symptoms. These supportive therapies are most effective when initiated early in life.
Multidisciplinary care may include speech therapy to improve communication skills, occupational therapy to develop daily living abilities, and physical therapy to enhance motor skills and coordination. Behavioral therapy can also be beneficial in managing challenging behaviors and promoting adaptive social interactions. Educational support, tailored to each person’s unique learning style and needs, is also an important component of ongoing care.