• Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit



CMD1N; CMH25; LGMD2G; T-cap; TELE; telethonin

Associated disorders

The TCAP gene is associated with autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) (MedGen UID: 400895) and autosomal dominant dilated cardiomyopathy (DCM) (MedGen UID: 2880). Additionally, the TCAP gene has preliminary evidence supporting a correlation with hypertrophic cardiomyopathy (HCM) (MedGen UID: 183649).

Pathogenic variants in TCAP cause approximately 3% of clinical cases of LGMD and an unknown percentage of CMD cases. Pathogenic TCAP variants are also associated with an unknown percentage of clinical cases of HCM and DCM in the absence of skeletal muscle involvement. Among a large cohort of Japanese and Korean patients, TCAP-related hypertrophic and dilated cardiomyopathy were found in 0.6% (2/346) and 0.7% (1/136) of patients, respectively.

The TCAP gene encodes the protein telethonin, which is present in both cardiac and skeletal muscles. Telethonin binds to the large scaffolding protein titin, which aids in maintaining the structure of the sarcomere complex, the primary role of which is muscle contraction.

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence, and select noncoding variants. Our assay provides a Q30 quality-adjusted mean coverage depth of 350x (50x minimum, or supplemented with additional analysis). Variants classified as pathogenic or likely pathogenic are confirmed with orthogonal methods, except individual variants that have high quality scores and previously validated in at least ten unrelated samples.

Our analysis detects most intragenic deletions and duplications at single exon resolution. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. If you are requesting the detection of a specific single-exon copy number variation, please contact Client Services before placing your order.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
TCAP NM_003673.3