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.
It is the same part of chromosome 15 that is usually affected in people with Angelman syndrome, although different genes are associated with the two disorders. People can have either Prader-Willi syndrome or Angelman syndrome, but they typically cannot have both. People normally inherit one copy of chromosome 15 from each parent. Some genes on this chromosome are turned on (active) only on the copy inherited from a person's father (the paternal copy).