FRAXE

Gene name / Alternate gene name

AFF2
FRAXE, FMR2

Protein

AF4/FMR2 family, member 2

Lab area

Genome Diagnostics - Molecular Genetics

Method and equipment

AFF2 5'UTR trinucleotide (CCG) repeat analysis via PCR

Expected turn-around time

Prenatal samples: 2 weeks Pregnancy/STAT: 2-3 weeks Routine: 4-6 weeks

Specimen type

Blood; gDNA.

For details about specimen requirements, please refer to: Specimen Type & Requirements (PDF).

Specimen requirements

Blood: 5-10 mL in EDTA, 0.5 mL in EDTA (neonate);
DNA-minimum 10 ug in 100 uL low TE (pH8.0)

Storage and transportation

Room Temperature

For details about specimen requirements, please refer to: Specimen Type and Requirements

Special requirements

Special Instructions for Genome Diagnostics Samples

If sample shipment >48 hours, ship on ice. The eligibility for this test is determined by the presence of a family history suggestive of X-linked intellectual disability; a pedigree must be provided for Fragile X E testing.

Shipping information

The Hospital for Sick Children

Division of Genome Diagnostics

555 University Avenue, Black Wing, Room 3416

Toronto, ON

Canada

M5G 1X8

Phone: 416-813-7200 ext. 2

Hours: Monday to Friday, 8 a.m. to 4:30 p.m.

Off hours: Please send to Rapid Response Laboratory, 555 University Avenue, Room 3642

Email Molecular Lab: molecular.lab@sickkids.ca

Email Cytogenetics: cytogenetics.requests@sickkids.ca

Requisition

FRAXE - requisition

Background and clinical significance

FRAXE is a form of non-syndromic X-linked intellectual disability characterized by mild intellectual disability. The FRAXE phenotype is quite variable, and tends to include slow learning, hyperactivity, attention problems and language delay. The gene associated with FRAXE is called FMR2. The normal gene contains a three base pair sequence, which is repeated on each X chromosome (called a CCG repeat). The principal mutation causing FRAXE is an expansion of the CCG repeat sequence within the FMR-2 gene.

See related information sheet: FRAXE Molecular Analysis

Disease condition

Fragile X E Syndrome