MARVELD2 gene testing (exon 4) – early non-syndromic AR deafness
Test covered by the reimbursement:
YES
Gender:
Woman/Man
Material:
Peripheral blood, Buccal swab
…
Turnover time:
3 weeks
STATIM:
1 week
Material:
Peripheral blood
| 1x 3 ml of whole blood in K3 EDTA tube
Storage after examination: week after the report is issued 2 – 8°C
Buccal swab
| 2x swab stick for buccal swab collection
Storage after examination: week after the report is issued 2 – 8°C
Isolated DNA from blood
| 10–100 ng/μL of isolated DNA from blood in a PCR tube of at least 15 μL.
Storage after examination: stored in a DNA archive without restriction 15°C
Isolated DNA from chorionic villi
| 30–100 ng/μL of isolated DNA from chorionic villi in a microtube (Eppendorf type)
Storage after examination: stored in a DNA archive without restriction 15°C
Isolated DNA from amniotic fluid
| 30–100 ng/μL of isolated DNA from amniocentesis in a microtube (Eppendorf type)
Storage after examination: stored in a DNA archive without restriction 15°C
Isolated DNA from cordocentesis
| 30–100 ng/μL of isolated DNA from cordocentesis in a microtube (Eppendorf type)
Storage after examination: stored in a DNA archive without restriction 15°C
DNA isolated from the product of conception
| 50–100 ng/μL in microtube (Eppendorf type)
Storage after examination: stored in a DNA archive without restriction 15°C
DNA isolated from cultured cells
| 30–100 ng/μL of isolated DNA from cultured cells in a microtube (Eppendorf type)
Storage after examination: stored in the DNA archive 15°C
Quick test description:
Sequencing the coding region of exon 4 in the MARVELD2 gene, which is a common cause of hearing loss in the Roma ethnic group.
Test details:
Homozygous mutations in the MARVELD2 gene (other name TRIC) are the cause of hearing loss in about 1% of the Pakistani population, with the most commonly proven mutation being c.1331+2 T>C (IVS4 + 2T>C). This mutation was also shown in the Czech Roma ethnic group, as a cause of hearing loss in 3 out of 20 Roma families tested. However, mutations in this gene have not been demonstrated in the general Czech deaf population (Brožková, et al., 2012). DFNB49 therefore seems to be the second most common cause of hearing loss in the Roma ethnic group and it is therefore advisable to test for it after excluding GJB2 mutations. The testing is performed by Sanger sequencing of the coding region of exon 4 in the MARVELD2 gene.