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.
When a deletion of chromosome 15q11-q13 region is found on the motherâs chromosome 15, the result is an entirely different syndrome called Angelman syndrome (AS). That is because there is also one gene in the Prader-Willi region that is imprinted, or turned off, on the fatherâs chromosome 15; people who lack this gene from their mother have AS rather than PWS.