Andersen-Tawil Syndrome
Cardiology section
Andersen-Tawil syndrome is a rare genetic disorder characterized by muscle weakness, periodic paralysis, and irregular heart rhythms (arrhythmias). These symptoms may be accompanied by distinctive facial and skeletal features. The severity and presentation of symptoms can
vary widely among individuals, even within the same family. Approximately 60 percent of cases are linked to mutations in the KCNJ2 gene, which disrupts potassium ion transport across muscle cell membranes, leading to periodic paralysis and irregular heart rhythm.
ABOUT ANDERSEN-TAWIL SYNDROME
UNDERSTANDING ANDERSEN-TAWIL SYNDROME
Insights into Andersen-Tawil Syndrome
The role of the KCNJ2 gene in bone development remains unclear, and the exact mechanism by which mutations in the gene contribute to skeletal changes and other physical abnormalities associated with Andersen-Tawil syndrome is yet to be fully elucidated.
In cases not linked to KCNJ2 gene mutations, accounting for about 40 percent and classified as type 2 (ATS2), the cause of Andersen-Tawil syndrome remains largely unknown. Research suggests that variations in at least one other potassium channel gene may contribute to the disorder in some of these cases.
The remaining genes associated with ATS include:
CACNA1C (Calcium Voltage-Gated Channel Subunit Alpha1 C)
KCNJ5 (Potassium Inwardly Rectifying Channel Subfamily J Member 5)
ABCC9 (ATP-Binding Cassette Subfamily C Member 9)
These genes play crucial roles in regulating ion channel function and membrane excitability in cardiac and skeletal muscle cells, and mutations in these genes can lead to the characteristic features of ATS, including periodic paralysis and cardiac arrhythmias.
Genetic testing can help identify mutations associated with ATS and guide clinical management and treatment decisions for affected individuals and their families. Early detection and intervention are essential for preventing or mitigating the serious complications associated with ATS, including sudden cardiac death.