Published 14/01/2019
Waardenburg Syndrome
NGS panel
Lab method: |
NGS panel with CNV analysis |
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
SThe A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Deletion/duplication analysis
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Indications for genetic testing:
- Confirmation of clinical diagnosis
- Carrier testing for at-risk relatives
- Genetic counseling
Waardenburg syndrome (WS) is a group of genetic conditions characterized by sensorineural hearing loss and pigmentary abnormalities of the iris, hair, and skin, along with dystopia canthorum. Hearing loss is congenital, typically non-progressive, either unilateral or bilateral, and sensorineural.
The classic sign of hair pigmentation anomaly with WS is white forelock appearing typically in the teen years. Ocular pigmentary manifestations may include complete or segmental heterochromia or hypoplastic or brilliant blue irides.
Waardenburg syndrome affects an estimated 1 in 20,000-40,000 people.
Four types of WS can be distinguished by physical characteristics and genetic cause. Types I and III are inherited in an autosomal dominant manner, types II and IV are autosomal recessive.
References:
Farrer LA et al. Waardenburg syndrome (WS) type I is caused by defects at multiple loci, one of which is near ALPP on chromosome 2: first report of the WS consortium. Am J Hum Genet. 1992;50:902–13.
Milunsky JM. Waardenburg Syndrome Type I. GeneReviews® 2001 July 30 (Updated 2014 Aug 7)
Shields CL et al. Waardenburg syndrome: iris and choroidal hypopigmentation: findings on anterior and posterior segment imaging. JAMA Ophthalmol. 2013;131:1167–73.
Tamayo ML et al. Screening program for Waardenburg syndrome in Colombia: clinical definition and phenotypic variability. Am J Med Genet A. 2008;146A:1026–31.
Published 02/07/2015
Waardenburg Syndrome
NGS panel
Lab method: |
NGS panel with CNV analysis |
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
SThe A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Deletion/duplication analysis
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Indications for genetic testing:
- Confirmation of clinical diagnosis
- Carrier testing for at-risk relatives
- Genetic counseling
Waardenburg syndrome (WS) is a group of genetic conditions characterized by sensorineural hearing loss and pigmentary abnormalities of the iris, hair, and skin, along with dystopia canthorum. Hearing loss is congenital, typically non-progressive, either unilateral or bilateral, and sensorineural.
The classic sign of hair pigmentation anomaly with WS is white forelock appearing typically in the teen years. Ocular pigmentary manifestations may include complete or segmental heterochromia or hypoplastic or brilliant blue irides.
Waardenburg syndrome affects an estimated 1 in 20,000-40,000 people.
Four types of WS can be distinguished by physical characteristics and genetic cause. Types I and III are inherited in an autosomal dominant manner, types II and IV are autosomal recessive.
References:
Farrer LA et al. Waardenburg syndrome (WS) type I is caused by defects at multiple loci, one of which is near ALPP on chromosome 2: first report of the WS consortium. Am J Hum Genet. 1992;50:902–13.
Milunsky JM. Waardenburg Syndrome Type I. GeneReviews® 2001 July 30 (Updated 2014 Aug 7)
Shields CL et al. Waardenburg syndrome: iris and choroidal hypopigmentation: findings on anterior and posterior segment imaging. JAMA Ophthalmol. 2013;131:1167–73.
Tamayo ML et al. Screening program for Waardenburg syndrome in Colombia: clinical definition and phenotypic variability. Am J Med Genet A. 2008;146A:1026–31.