|
High
Resolution Banding
Description
Includes special synchronized PHA-stimulated culture of peripheral
blood lymphocytes and preparation of Giemsa-banded chromosomes.
Banding is at the 650 or higher band level of resolution. Chromosome
analysis includes partial karyotypes of at least three different
pairs of homologous chromosomes for each chromosome, two banded
karyotypes, detailed examination of ten cells, and 20 cells total
counted.
Indications
High resolution banding chromosome analysis is helpful to identify
subtle chromosome rearrangements such as microdeletions and cryptic
translocations that may go undetected by routine chromosome analysis.
This test is often ordered by clinical geneticists who suspect a
patient may have a specific chromosomal syndrome.
Specimen Requirements
5-8 cc blood (2 cc for infants and small children) in green-top
(sodium heparin) tube; invert several times to mix blood. Culture
of clotted blood often does not result in spontaneously dividing
cells necessary for cytogenetic analysis. Other anticoagulants such
as lithium heparin may be harmful to the viability of the cells.
Label tube with patient's name and laboratory control number. Send
to Great Lakes Genetics at room temperature within 24 hours of collection.
May be refrigerated overnight. Specimen cannot be frozen. Indicate
suspected disorder on requisition form.
Reference Value
46,XX or 46,XY
Turn Around Time
2-3 weeks
CPT Codes
882G2 - chromosome analysis, congenital disorder
88230 - tissue culture for chromosome analysis
88289 - chromosome analysis, high resolution
|
