Mental retardation and developmental delay
Dysmorphic signs
Missed abortions
Subtelomeric FISH
General Information
The subtelomeric regions of the chromosomes are gene rich DNA sequences close to the ends (telomeres) of the chromosomes. Fluorescence-in-situ-Hybridisation (FISH-Analysis) revealed small cryptic chromosomal imbalances in patients with mental retardation, especially in alliance with delevopmental retardation and dysmorphic signs not detectable with standard karyotyping.
Balanced subtelomeric translocations can be causative for unbalanced offspring or missed abortions.
Diagnostic
Indication
Method
FISH-analysis using a set of probes homologous to specific sequences in the subtelomeric regions of all chromosomes.
Sample Requirement
2 - 5 ml of heparinised blood
Duration
1 - 2 weeks