The laboratory performs high-resolution chromosome analysis on peripheral blood specimens.
About the Cytogenetics Laboratory:
Tests also include chromosome breakage, fluorescence in situ hybridization (FISH), and microarray analysis. Cytogenetic analysis is performed by certified clinical laboratory specialists and reviewed by a certified Ph.D. clinical cytogeneticist.
Indications for Cytogenetic Analysis:
- Family history of chromosome anomaly
- Recurrent spontaneous abortions
- Still birth and neonatal deaths
- Fetal anomalies detected with ultrasound
- Intellectual disability
- Dysmorphic features
- Females with primary or secondary amenorrhea
- Ambiguous genitalia
- Ataxia telangiectasia and Fanconi's anemia
Peripheral Blood High Resolution Chromosome Analysis
Lymphocytes are stimulated with mitogens and synchronized to yield elongated chromosomes. These long chromosomes permit high resolution analysis to detect more subtle abnormalities.
Chromosomal Breakage Analysis
Peripheral blood samples are treated with DEB (diepoxybutane) or X-irradiated to induce breakage in individuals with suspected diagnosis of Fanconi's anemia or Ataxia telangiectasia, respectively. The frequency of breaks is compared to a normal control run in parallel and also to our database of positive and negative individuals.
Specimens for this test must be drawn and shipped on Monday for overnight delivery on Tuesday.
Fluorescence in situ hybridization (FISH) Analysis
Fluorescence in situ hybridization (FISH) is used to detect alterations in specific chromosomal regions from metaphase spreads and/or interphase nuclei. These probes show specific changes, such as amplifications, deletions, or translocations of specific genes, loci, or chromosomal regions. FISH may be performed on peripheral blood, bone marrow, fibroblast, or lymphoblast cultures.
Array SNP-based Analysis
Our microarray platform contains probes targeting single nucleotide polymorphisms (SNPs) and non-polymorphic markers. Both types of probes are utilized to detect copy number changes (CNC), including deletions, duplications, and unbalanced rearrangements. SNP probes provide allelic information and are used to detect copy number neutral loss of heterozygosity (LOH) or uniparental disomy (UPD). Two genotyping measurements, normalized intensity and allelic ratios, are performed utilizing specialized software and allow the identification of CNC and LOH/UPD. The array will not identify balanced rearrangements, including reciprocal and Robertsonian translocations, insertions or inversions, nor will it detect point mutations.
When ordering this test, please include the signed Informed Consent for Genetic Testing Form.
Visit our Requisition Forms page for sample shipping instructions and forms to submit with your samples.