A regular expression is a pattern that the regular expression engine attempts to match in input text. A pattern consists of one or more character literals, operators, or constructs. For a brief introduction, see .NET Framework Regular Expressions.
(For our list of subjects with an imprinting defect, click here.). UBE3A Mutation. Malfunction of the UBE3A gene on the maternal chromosome #15 seems to be the cause of Angelman syndrome. In the case of a UBE3A mutation, there is a mistake in the genetic code of the UBE3A gene.
Deletion. This diagnosis accounts for 70% of people with Angelman syndrome. Individuals with a deletion have a piece missing on their maternal chromosome #15. (Deletions on the paternal chromosome #15 are the cause for the disorder Prader Willi) This is a spontaneous mutation which is not hereditary.