22q11.2 deletion syndrome, also called DiGeorge syndrome or Velo-Cardio-Facial syndrome (VCFS), is caused by a missing piece of chromosome number 22. About one in every 2,000 babies is born with 22q11.2 deletion syndrome. The majority of children with this disorder have heart defects, immune system problems, and specific facial features. Most children with 22q.11.2 deletion syndrome have mild-to-moderate intellectual disability and speech delays; some will also have low calcium levels, kidney problems, feeding problems, and/or seizures. About one in five children with 22q11.2 deletion syndrome have autism spectrum disorder; 1 in 4 adults with 22q11.2 deletion syndrome have a psychiatric illness, like schizophrenia.