Patients with CIC haploinsufficiency syndrome present with a number of symptoms that affect different parts of the body. Almost all patients have developmental delay or intellectual disability. Other features commonly observed include autism, seizures, and attention deficit hyperactivity disorder (ADHD). The severity of these features can vary greatly, some patients having certain features while not having others.
Additionally, CIC is thought to have a role in preventing cancer development. Of all identified patients with CIC haploinsufficiency syndrome, one has developed lymphoma. There is not enough information to determine if patients with CHS are at increased risk of cancer, however, due to the function of the gene, we recommend preventative cancer screening.