KCNQ4 Potassium Voltage Gated Channel (Deafness Genetic Test), Whole Blood

KCNQ4 Potassium Voltage Gated Channel (Deafness Genetic Test)

Order Code:	KCNQ4
Epic Lab Code:	LAB7324
Order Form:	A-1a Miscellaneous Request or Epic Req

Commercial Mail-out Laboratory
6240 RCP
356-3527

Specimen:

Whole Blood

Collection Medium:

	and
Pink top tube	and	Pink top tube

Alternate Collection Media:

Lavender top tube 4 mL (EDTA)

Minimum:

Preferred Minimum: 8 mL whole blood Absolute Minimum: 4 mL whole blood

Analytic Time:

3 months

Reference Range:

None detected

Interpretive Data:

DFNA2 Two genes are responsible for autosomal dominant nonsyndromic sensorineural hearing loss at the DNFA2 locus, KCNQ4 and GJB3. Both of these genes map to chromosome 1p34-p35. KCNQ4 KCNQ4 is voltage-gated potassium channel expressed in the outer hair cells of the cochlea. The gene has 14 exons that encode a 695 amino acid protein. Mutations in KCNQ4 are found persons with high-frequency, autosomal dominant, nonsyndromic sensorineural hearing loss. At least eight different mutations in KCNQ4 have been identified in families segregating autosomal dominant nonsyndromic hearing loss. Sensitivity is greater than 98%.

Comments:

Please print, complete and submit the Deafness Testing Requisition from the Molecular Otolaryngology & Renal Research Laboratory, to Specimen Control/Mailouts with the specimen and the Epic Requisition.

Methodology:

Screening for KCNQ4 is performed via DHPLC and sequencing. Oligonucleotide primers have been designed to amplify each exon. Amplified samples are run on the DHPLC; abnormal elution profiles are sequenced to identify specific mutations. Exons carrying known SNPs are directly sequenced.

CPT Code:

83891, 83894, 83898 (x12), 83903 (x12), 83904 (x10)