14-21402335-C-T

Variant names:

• chr14-21402335-C-T
• rs1555314736
• NM_001170629.2:c.3882+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_001170629.2(CHD8):​c.3882+1G>A variant causes a splice donor, intron change involving the alteration of a 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 Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHD8 NM_001170629.2 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.88
• Publications: 0 publications found

Genes affected

CHD8 (HGNC:20153): (chromodomain helicase DNA binding protein 8) This gene encodes a member of the chromodomain-helicase-DNA binding protein family, which is characterized by a SNF2-like domain and two chromatin organization modifier domains. The encoded protein also contains brahma and kismet domains, which are common to the subfamily of chromodomain-helicase-DNA binding proteins to which this protein belongs. This gene has been shown to function in several processes that include transcriptional regulation, epigenetic remodeling, promotion of cell proliferation, and regulation of RNA synthesis. Allelic variants of this gene are associated with autism spectrum disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2016]

CHD8 Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• autism

  Inheritance: AD Classification: STRONG Submitted by: G2P
• intellectual developmental disorder with autism and macrocephaly

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• intellectual disability

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• congenital myasthenic syndrome

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.021688614 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 14-21402335-C-T is Pathogenic according to our data. Variant chr14-21402335-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 521474.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001170629.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHD8	NM_001170629.2	MANE Select	c.3882+1G>A		splice_donor intron	N/A	NP_001164100.1
	CHD8	NM_020920.4		c.3045+1G>A		splice_donor intron	N/A	NP_065971.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHD8	ENST00000646647.2	MANE Select	c.3882+1G>A		splice_donor intron	N/A	ENSP00000495240.1
	CHD8	ENST00000430710.8	TSL:1	c.3045+1G>A		splice_donor intron	N/A	ENSP00000406288.3
	CHD8	ENST00000557364.6	TSL:5	c.3882+1G>A		splice_donor intron	N/A	ENSP00000451601.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Dec 28, 2016

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Intellectual developmental disorder with autism and macrocephaly Pathogenic:1

Oct 01, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		7.9
GERP RS		5.7
Mutation Taster		=0/100	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1555314736; hg19: chr14-21870494;