Indications for DiGeorge/Velocardiofacial Syndrome
DiGeorge and Velocardiofacial syndromes (VCFS) both are caused by 22q11 deletions. Fetus with congenital heart defect on fetal ultrasound. Individuals affected with DiGeorge syndrome are characterized by congenital heart defects, an absent or hypoplastic thymus, hypocalcemia, cleft lip and/or palate, microcephaly, immune deficiency, renal anomalies, psychiatric problems and learning difficulties.
- Amniotic fluid Discard the first 2 ml of fluid to reduce the risk of maternal cell contamination. Aseptically transfer the specimen into sterile plastic conical tubes labeled with patient’s name and date of birth.
- CVS Aseptically transfer the specimen into sterile plastic conical tubes containing sterile transport medium. Label tube with patient’s name and date of birth.
- Peripheral blood Collect whole blood in a green top tube (sodium heparin). Label tube with patient’s name and date of birth.
A completed test requisition form must be included with every sample. A transport kit is available upon request.
FISH analysis is performed following cytogenetic analysis
Room temperature (DO NOT refrigerate, freeze or centrifuge)
Laboratory testing for DiGeorge/Velocardiofacial Syndrome is performed on metaphase chromosomes utilizing Fluorescence in situ hybridization targeting chromosome 22.
Causes for Rejection
Frozen specimen, inappropriate container
24-48 hrs after completion of cytogenetic analysis