Uniparental Disomy (UPD) Studies
|Disorders||Prader-Willi syndrome (Chromosome 15)
Angelman syndrome (Chromosome 15)
Russell-Silver syndrome (Chromosome 7)
|Clinical info||Uniparental disomy describes the abnormal assortment of chromosomes from parent to child. Normally, one-half of the genetic material is derived from each parent. In uniparental disomy, the chromosome number is correct, but both members of a chromosome pair or segments of a chromosome pair are inherited from the same parent. The detection of uniparental disomy involves PCR analysis of genetic material from the affected child and both parents. Genetic conditions that are often associated with uniparental disomy include Prader-Willi syndrome, Angelman syndrome, Russell-Silver syndrome and various other malformation syndromes.|
|Indications||UPD testing is useful to confirm the diagnosis and to identify the etiology of the disorder within a family as well as to establish the inheritance of Robertsonian translocations.|
|Associated Tests||Prader-Willi/Angelman methylation studies, FISH for Prader-Willi or Angelman syndromes, UBE3A sequencing|
|Detection||UPD causes approximately 25% of cases of Prader-Willi syndrome and approximately 7% of cases of Angelman syndrome.|
|Specimen Requirements||5 to 10 ml of peripheral blood from proband and both parents collected in an EDTA (lavender top) Vacutainer tube is preferred. The minimal blood needed for reliable DNA isolation is 3 ml|
|Transport||The specimen should be kept at room temperature and delivered via overnight shipping. FedEx is preferred. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen. Samples collected on Friday can be safely designated for Monday delivery.|
|Turnaround time||3 weeks|
|Prenatal testing||Prenatal diagnosis is available. Additional fees for cell culture and maternal cell contamination may apply. Maternal cell contamination studies are required for all prenatal molecular tests. Contact the laboratory prior to sending a prenatal specimen.|
$500 (for each UPD study)
Prenatal diagnosis is $1000. Please contact the laboratory for more information.
Molecular Diagnostic Lab
The Molecular Diagnostic Lab offers DNA analysis for many genetic disorders via gene sequencing, targeted mutation analysis, MLPA deletion/duplication testing, trinucleotide repeat analysis and next generation sequencing panels.