Mosaic mutations in PIK3CA have been found to be the genetic cause of M-CM. Other overgrowth conditions with distinct phenotypes have also been found to be caused by mosaic mutations in PIK3CA. How different mutations in this gene result in a variety of defined clinical syndromes is still being clarified. Mutations in PIK3CA have not been found in a non-mosaic state in any of these disorders, so it is unlikely that the conditions could be inherited.
Macrocephaly-capillary malformation
Dandy–Walker malformation
Autosomal dominant porencephaly type I
Ramsay Hunt syndrome type 2
Ramsay Hunt syndrome type 1
complications of Chiari malformation
Tolosa–Hunt syndrome
Craniosynostosis–anal anomalies–porokeratosis syndrome