Titin Variants in Dilated Cardiomyopathy

TTN Transcript / Exon Structure & Truncating Variants in Cardiomyopathy Studies

Titin - Exon 222

Details for Exon 222 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 222 are displayed below.

HG19 Genomic		HG38 Genomic		Locus Reference Genomic		Meta-Transcript
Start	End	Start	End	Start	End	Start	End
179,505,357	179,505,268	178,640,630	178,640,541	195,173	195,262	40,634	40,723

Transcripts

Exon 222 occurs in the following Titin transcripts (the number indicates the exon rank of exon 222 in each transcript).

META	N2BA	N2B	N2A	NOVEX-1	NOVEX-2	NOVEX-3
221	171	49	170	50	50	-

Functional Data

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

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 95% 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

No TTN truncating variants affecting this exon have been described in major published studies.

Sequence

Size of Exon: 90 bases Ensembl ID: ENSE00002245689

TACCAGAACCACCACCTCCAAAACCTGTTGAAGAGGTTGAAGTACCTACTGTTACAAAAAGGGAAAGGAAGATTCCTGAACCAACAAAAG

ATGC = coding sequence, ATGC = non-coding sequence