DYSKERATOSIS CONGENITA

TINF2 Sequencing

DNA ANALYSIS

Dyskeratosis congenital (DC) is a rare inherited bone marrow failure syndrome associated with the triad of reticulated skin hyperpigmentation, nail dystrophy, and oral leukoplakia. DC is both clinically and genetically heterogeneous. Six genes and three forms of inheritance, namely X-linked, autosomal dominant and autosomal recessive, are reported in patients with DC. TINF2 gene mutations are associated with autosomal dominant form of DC. TINF2 encodes protein TERF1-interacting nuclear factor 2. It is located on 14q12 and has nine coding exons. Sequence analysis of the entire coding region of the TINF2 gene is available on a clinical basis at Baylor Medical Genetics Laboratories.

Reasons For Referral:

Confirmation of clinical diagnosis
Carrier testing of known familial mutations
Prenatal diagnosis (known mutations only).

Testing Methodology:

PCR amplification of all the 9 exons contained in the TINF2 gene coding region will be performed on patient genomic DNA. Direct sequencing of amplification products is performed in both the forward and reverse directions using automated fluorescence dideoxy sequencing methods.

Specimen Requirements:

Blood: EDTA (purple-top) tubes: Adults: 14 cc; Child: 6 cc; Infant: 2-3 cc
Requisition form must accompany the specimen. To receive forms, additional information or specimen collection kits, please contact the laboratory. Please call our laboratory for specific requirements for prenatal testing.

Turnaround Time:

Index: 4 weeks
Known Familial Mutation: 3 weeks

CPT Codes and Prices:

Index: 83912, 83894, 83891, 83898x7, 83904x14, 83909x14
Known Familial Mutation: 83912, 83894, 83891, 83898, 83904x2, 83909x2

Shipping Information

Forms:

>> Gene Sequencing Requisition
>> Prenatal Requisition

References:

Savage et al (2008). TINF2, a component of the shelterin telomere protection complex, is mutated in dyskeratosis congenita. Am. J. Hum. Genet. 82: 501.
Walne et al (2008). TINF2 mutations result in very short telomeres: analysis of a large cohort of patients with dyskeratosis congenita and related bone marrow failure syndromes Blood 112: 3594.

Test Codes:

Index: 6645
Known Familial Mutation: 6646
Prenatal (Known Familial Mutation Only): 6647