Titin Variants in Dilated Cardiomyopathy

TTN Transcript / Exon Structure & Truncating Variants in Cardiomyopathy Studies

Titin - Exon 346

Details for Exon 346 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 346 are displayed below.

HG19 Genomic HG38 Genomic Locus Reference Genomic Meta-Transcript
StartEnd StartEnd StartEnd StartEnd
179,409,233 179,408,928 178,544,506 178,544,201 291,297 291,60295,723 96,028

Transcripts

Exon 346 occurs in the following Titin transcripts (the number indicates the exon rank of exon 346 in each transcript).

METAN2BAN2BN2ANOVEX-1NOVEX-2NOVEX-3
345 295 173 294 174 174 -

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 121.

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 99% in GTEx (LV tissue of 105 samples from Genotype-Tissue Expression project). (See Ref. 1 for details)

Symmetry: This exon is symmetric, i.e. the length of the exon is a multiple of three and therefore removal of it will not 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
NEJM 2012DCM-CTSFDC033-434c.95966delAp.Asn31989fsframeshift

Sequence

Size of Exon: 306 bases           Ensembl ID: ENSE00001389240

ATACCCCTGGACCACCTTCTGCTCCAAGAGTTGTGGATACCACCAAACACAGCATTAGTTTGGCATGGACCAAACCCATGTACGATGGTGGTACTGACATTGTAGGATATGTTCTGGAAA
TGCAAGAGAAGGACACTGATCAGTGGTACCGAGTGCATACCAATGCCACAATAAGAAATACTGAATTCACTGTGCCAGACCTTAAAATGGGCCAGAAATATTCCTTCAGAGTTGCTGCCG
TGAACGTGAAGGGTATGAGCGAATACAGCGAATCAATTGCTGAAATTGAGCCCGTGGAAAGAATAG

ATGC = coding sequence, ATGC = non-coding sequence