Titin Variants in Dilated Cardiomyopathy

TTN Transcript / Exon Structure & Truncating Variants in Cardiomyopathy Studies

Titin - Exon 256

Details for Exon 256 of the Titin gene - Sequence Coordinates, Associated Transcripts, Functional Data, Truncating Variants and Sequence.

The exon number is based on the LRG numbering, as recommended for clinical reporting.

Coordinates

The genomic coordinates of HG19 and Locus Reference Genomic (LRG) and the CDS coordinates of the Titin meta-transcript for exon 256 are displayed below.

HG19 Genomic Locus Reference Genomic Meta-Transcript
StartEnd StartEnd StartEnd
179,481,961 179,481,847 218,569 218,68347,761 47,875

Transcripts

Exon 256 occurs in the following Titin transcripts (the number indicates the exon rank of exon 256 in each transcript).

METAN2BAN2BN2ANOVEX-1NOVEX-2NOVEX-3
255 205 83 204 84 84 -

Functional Data

Region: This exon occurs in the A-band region of the titin protein.

Domains: This exon codes for the following domain(s) - Fibronectin type-III 3.

PSI: The "proportion spliced-in" (an estimate of the percentage of TTN transcripts that incorporate this exon based on RNAseq data) is 100% in DCM (LV tissue of 84 end-stage patients) and 84% in GTEx (LV tissue of 105 samples from Genotype-Tissue Expression project). (See Ref. 1 for details)

Symmetry: This exon is assymmetric, i.e. the length of the exon is not a multiple of three and therefore removal of it will alter the reading frame.

References
1. A. M. Roberts, J. S. Ware, D. S. Herman et al. Integrated allelic, transcriptional, and phenomic dissection of the cardiac effects of titin truncations in health and disease. Sci. Transl. Med. 7, 270ra6 (2015).

Truncating Variants

The following TTN truncating variants affecting this exon have been described in major published studies (click on the study name for more details):

StudyCohortPatient IDVariant (CDS)Variant (protein)Variant Type
STM 2015DCM-PRO10DR00069c.47875+1G>Aessential splice site

Sequence

Size of Exon: 115 bases           Ensembl ID: ENSE00002308924

GTTACCGGATTGGAAAAAGGAAATAAATATTTATATAGAGTATCTGCAGAAAATAAAGCTGGTGTTTCAGATCCATCTGAAATTCTTGGTCCTCTCACCGCTGACGATGCATTTG

ATGC = coding sequence, ATGC = non-coding sequence