Background:
Microcephaly is defined by a patient’s head circumference dropping below two standard deviations relative to normal children of the same age. Individuals with microcephaly may also have slow brain development and at times display intellectual disabilities, seizures/epilepsy or other dysmorphic features. This sequencing test assess genes that associates with syndromes where microcephaly is a clinical feature, these include Rett syndrome, Angelman syndrome, autosomal recessive primary microcephaly. While conditions can follow a recessive form but may also be dominant or X-linked.
Reasons for Referral:
- Head circumference measures two standard deviations below average
- Carrier testing
- Positive family history
Methodology:
Next generation sequencing will analyze the exons or coding regions of 28 microcephaly-associated genes using Illumina NextSeq 500 technology. Samples are prepared using hybridization probes to enrich exonic regions. Promoter, intronic, etc. regions are not assessed on our assay, but may contain variants that impact gene function.
Microcephaly Panel (28 genes): ASPM, ATR, ATRX, CASK, CDK5RAP2, CDKL5, CENPJ, CEP152, DHCR7, FOXG1, IER3IP1, MCPH1, MECP2, MYCN, NIPBL, PCNT, RAB18, RAB3GAP1, RAB3GAP2, RBBP8, SLC25A19, SLC9A6, STIL, TCF4, TUBB3, UBE3A, WDR62, ZEB2
Specimen Requirements:
Blood: EDTA or ACD (Solution A or B):
- Adult: 5 mL
- Child: 5 mL
- Infant: 2-3 mL
A REQUISITION FORM MUST ACCOMPANY ALL SAMPLES. Please include detailed clinical information, including ethnicity, clinical history, and family history.
Test Performed (Days):
Weekly
Turn Around Time:
8 weeks
Shipment Sensitivity Requirements:
- Package and ship specimen to remain cold, but not frozen.
- Ship via overnight express, using the FedEx priority overnight label provided.
- Contact Client Services for shipping kits and instructions at (855) 535-1522.
References:
Additional Info: