Behavior and intelligence in children with the 22q11.2-deletion syndrome

The 22q11 deletion syndrome (22q11DS) is a genetic disorder with an estimated prevalence of 1 in 4000 live births. We found that children with the syndrome have a distinctive behavioral phenotype, characterized by social problems and withdrawn behavior. They also have lower mean intelligence. Although in the general population, lower intelligence is associated with more behavioral problems, in children with 22q11DS no such relationship can be found. Another remarkable result of our study is that 42% of children shows a significant decline in intelligence between ages 7½ and 15½. It is known that children with 22q11DS are at high risk for developing psychosis. This decline in IQ could be one of the first signs that a psychosis might develop later in life. It is therefore recommended that children with this syndrome get early treatment and regular follow-up by specialized teams.