The National Institute of Health Office and Rare Disease Research characterizes PCDH19 gene-related<unk>  as a rare disorder. Rare diseases, by definition, are diseases that affect fewer than 200,000 people in the United States. Since the mutation associated with PCDH19 gene-related<unk>  was only recently identified in 2008, the true incidence of the disease is generally unknown. Although formal epidemiologic data is not available, results from diagnostic screening indicates that approximately 1 out of 10 girls who have seizure onset before five years of age may have PCDH19 gene mutations. Additionally, PCDH19 screening of several large cohorts of<unk>  with early onset febrile-related<unk>  has resulted in a rate of approximately 10% of mutation-positive individuals.
Epilepsy-intellectual disability in females
Schizophrenia and tobacco smoking
Supernumerary nipples–uropathies–Becker's nevus syndrome
Autism – Tics, AD/HD, and other Comorbidities
Mental retardation and microcephaly with pontine and cerebellar hypoplasia
Cerebellar ataxia, neuropathy, vestibular areflexia syndrome
Craniosynostosis–anal anomalies–porokeratosis syndrome
Blepharophimosis, ptosis, epicanthus inversus syndrome