Treacher Collins Syndrome
NGS panel
Genes
(full coding
region): |
POLR1C, POLR1D, TCOF1 |
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
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. |
Deletion/duplication analysis of the TCOF1 gene
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 family members
- Genetic counseling
Treacher Collins syndrome (TCS) is a congenital disorder characterized by craniofacial deformities, external ear abnormalities, and eye anomalies. The most characteristic features of TCS are micrognathia, conductive hearing loss, coloboma of the lower eyelid, and absence of the lower eyelashes. Less common signs include cleft palate and unilateral or bilateral choanal stenosis or atresia.
TCS affects an estimated 1 in 50,000 people. The disorder has an autosomal dominant pattern of inheritance. Approximately 1% of TCS is inherited in an autosomal recessive manner.
References:
Chiara C et al. Novel mutations of TCOF1 gene in European patients with treacher Collins syndrome. 2011. Medical Genetics 12.
Katsanis SH and Jabs EW. Treacher Collins Syndrome. GeneReviews®. 2004 July 20 (Updated 2012 Aug 30)
Trainor PA et al. Treacher Collins syndrome: etiology, pathogenesis and prevention. 2008. European Journal of Human Genetics 17 (3): 275–283.