9-108874894-C-T

Variant names:

• chr9-108874894-C-T
• rs143674809
• NM_003640.5:c.3931+1G>A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_003640.5(ELP1):​c.3931+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ELP1 NM_003640.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 3.44

Genes affected

ELP1 (HGNC:5959): (elongator acetyltransferase complex subunit 1) The protein encoded by this gene is a scaffold protein and a regulator for three different kinases involved in proinflammatory signaling. The encoded protein can bind NF-kappa-B-inducing kinase and I-kappa-B kinases through separate domains and assemble them into an active kinase complex. Mutations in this gene have been associated with familial dysautonomia. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ELP1	NM_003640.5	c.3931+1G>A		splice_donor_variant, intron_variant	Intron 36 of 36	ENST00000374647.10	NP_003631.2
ELP1	NM_001318360.2	c.3589+1G>A		splice_donor_variant, intron_variant	Intron 36 of 36		NP_001305289.1
ELP1	NM_001330749.2	c.2884+1G>A		splice_donor_variant, intron_variant	Intron 34 of 34		NP_001317678.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ELP1	ENST00000374647.10	c.3931+1G>A		splice_donor_variant, intron_variant	Intron 36 of 36	1	NM_003640.5	ENSP00000363779.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 27

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Familial dysautonomia Uncertain:1

Sep 16, 2020

Natera, Inc.

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

not provided Uncertain:1

Oct 27, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. This sequence change affects a donor splice site in the last intron (intron 36) of the IKBKAP gene. While this is not anticipated to result in nonsense mediated decay, it likely alters RNA splicing and results in a disrupted protein product. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with IKBKAP-related disease. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	31
DANN	Uncertain	0.98
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Benign	0.74	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs143674809; hg19: chr9-111637174;