del(15q)(q11.2q13), SNRPN, CEP15, PML
Fluorescence in situ Hybridization (FISH)
*performed at our affiliate laboratory
5.0 mL (min. 3.0 mL) whole blood, sodium heparin
Protect from extreme temperature. Ship with cool pack (refrigerated). Ship on Saturday for Monday delivery only if sample is protected from extreme temperature.
Clotted Specimen; Specimen exposed to extreme temperature; Anticoagulant or collection vessel toxic to cells; Insufficient number of cells; Specimen exposed to fixative
Presence or absence of the microdeletion
It is recommended that all FISH studies be done in conjunction with routine cytogenetic studies. If the FISH result is normal, a chromosome analysis allows identification of more complex abnormalities.
Angelman syndrome is a complex genetic disorder related to chromosome 15. Mutations in the UBE3A gene cause Angelman syndrome. People normally inherit one copy of the UBE3A gene from each parent. Both copies of this gene are active in many of the body’s tissues. In the brain, however, only the copy inherited from a person’s mother (the maternal copy) is active. This parent-specific gene activation is called genomic imprinting. If the maternal copy of the UBE3A gene is lost because of a gene mutation, a person will have no active copies of the gene in the brain. This loss of gene function likely causes many of the characteristic features of Angelman syndrome. Approximately 70% of individuals with AS have a 4- to 6-Mb deletion of 15q11.2-q13.