PURA and PURA-related severe neonatal hypotonia-seizures-encephalopathy syndrome due to a point mutation: The main difference between the two conditions is that 5q31.3 microdeletion syndrome is caused by a nonrecurrent genomic 5q31.3 deletion, which may encompass all or a part of PURA (10% of affected individuals; [6]), while PURA syndrome is caused by gene variants in the PURA locus.