PTEN and Neurodevelopmental delay: This “lower than expected” yield from PTEN sequencing may be due to the bias in defining macrocephaly or the fact that many macrocephalic patients in our cohort may have NDD other than ASD, which is the main symptom associated with PTEN. While this supports the decision to move PTEN to the end of the algorithm, given the extremely low yield of PTEN testing, we are considering replacing it with a more comprehensive next generation sequencing test which covers more genes and has a higher yield in NDDs.