TMCO1 Defect Syndrome is a rare genetic disease caused by loss of function of a protein called Transmembrane and Coiled-coil domains1 (TMCO1). The TMCO1 gene is responsible for providing instructions for making a specific protein found in the endoplasmic reticulum (storage area for Ca++ions) within the cell. With a mutation of this gene, the channels cannot form properly and excess Ca++ will accumulate in the endoplasmic reticulum; this imbalance causes problems in many tissues and organs.
TMCO1 Defect Syndrome is inherited in an autosomal recessive manner, meaning that both copies of the inherited gene have a mutation in an affected individual. The defective (mutated) gene is carried by both unaffected parents and can be passed to a future child with a 50% chance of being an asymptomatic carrier and a 25% chance of being affected. Screening for family members with increased risk of this condition is recommended. Genetic testing is offered as specifically targeted testing for known familial mutations in the TMCO1 gene or whole exome/genome sequencing.
TMCO1