Titin Variants in Dilated Cardiomyopathy

TTN Transcript / Exon Structure & Truncating Variants in Cardiomyopathy Studies

Titin - Exon 252

Details for Exon 252 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 252 are displayed below.

HG19 Genomic HG38 Genomic Locus Reference Genomic Meta-Transcript
StartEnd StartEnd StartEnd StartEnd
179,483,580 179,483,311 178,618,853 178,618,584 216,950 217,21946,697 46,966

Transcripts

Exon 252 occurs in the following Titin transcripts (the number indicates the exon rank of exon 252 in each transcript).

METAN2BAN2BN2ANOVEX-1NOVEX-2NOVEX-3
251 201 79 200 80 80 -

Functional Data

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

Domains: This exon codes for the following domain(s) - Ig-like 95.

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 89% 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
RECOVERY 2016DCM-REC20JH01781c.46782C>Ap.Y15594Xnonsense
PAED 2016ADOLESCENTUK-19c.46782C>Ap.Y15594Xnonsense
STM 2015DCM-ES20JH01781c.46782C>Ap.Tyr15594*nonsense
LMM 2014ALL-CASES116c.46773T>Ap.Tyr15591Xnonsense
LMM 2014ALL-CASES119c.46782C>Ap.Tyr15594Xnonsense

Sequence

Size of Exon: 270 bases           Ensembl ID: ENSE00002232521

CTGCACCAAAAATCAAGACAGCTGACCAAGACCTTGTGGTTGATGTTGGCAAGCCTCTGACAATGGTGGTGCCATATGATGCCTACCCCAAAGCAGAAGCTGAATGGTTTAAAGAAAATG
AACCTTTATCTACAAAAACCATTGATACTACGGCTGAACAAACTTCTTTCAGAATTTTAGAAGCCAAGAAAGGAGACAAAGGGAGGTATAAAATTGTGCTTCAGAACAAACATGGAAAAG
CAGAAGGATTCATCAATTTAAAAGTTATTG

ATGC = coding sequence, ATGC = non-coding sequence