6-24301742-AT-ATT

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_016356.5(DCDC2):​c.529dupA​(p.Ile177AsnfsTer20) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,613,970 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

DCDC2
NM_016356.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 0.780

Publications

4 publications found
Variant links:
Genes affected
DCDC2 (HGNC:18141): (doublecortin domain containing 2) This gene encodes a doublecortin domain-containing family member. The doublecortin domain has been demonstrated to bind tubulin and enhance microtubule polymerization. This family member is thought to function in neuronal migration where it may affect the signaling of primary cilia. Mutations in this gene have been associated with reading disability (RD) type 2, also referred to as developmental dyslexia. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jan 2013]
DCDC2 Gene-Disease associations (from GenCC):
  • ciliopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
  • isolated neonatal sclerosing cholangitis
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • nephronophthisis 19
    Inheritance: AR Classification: STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • hearing loss, autosomal recessive
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Senior-Boichis syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • nonsyndromic genetic hearing loss
    Inheritance: AR Classification: LIMITED Submitted by: ClinGen
  • autosomal recessive nonsyndromic hearing loss 66
    Inheritance: Unknown, AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-24301742-A-AT is Pathogenic according to our data. Variant chr6-24301742-A-AT is described in ClinVar as Pathogenic. ClinVar VariationId is 417769.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_016356.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
DCDC2
NM_016356.5
MANE Select
c.529dupAp.Ile177AsnfsTer20
frameshift
Exon 4 of 10NP_057440.2
DCDC2
NM_001195610.2
c.529dupAp.Ile177AsnfsTer20
frameshift
Exon 5 of 11NP_001182539.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
DCDC2
ENST00000378454.8
TSL:1 MANE Select
c.529dupAp.Ile177AsnfsTer20
frameshift
Exon 4 of 10ENSP00000367715.3

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152094
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251436
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000123
AC:
18
AN:
1461876
Hom.:
0
Cov.:
30
AF XY:
0.0000124
AC XY:
9
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000144
AC:
16
AN:
1112008
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
2
3
5
6
8
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152094
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74298
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41418
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Isolated neonatal sclerosing cholangitis Pathogenic:2
May 17, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

Mar 28, 2017
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

not provided Pathogenic:2
Apr 11, 2017
Eurofins Ntd Llc (ga)
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jan 18, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at a significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 30078246, 27469900)

Autosomal recessive nonsyndromic hearing loss 66;C4479344:Isolated neonatal sclerosing cholangitis Pathogenic:1
Oct 30, 2019
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in DCDC2 are known to be pathogenic (PMID: 25557784). This variant has been reported in siblings affected with neonatal sclerosing cholangitis (PMID: 27469900). ClinVar contains an entry for this variant (Variation ID: 417769). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Ile177Asnfs*20) in the DCDC2 gene. It is expected to result in an absent or disrupted protein product.

Autosomal recessive nonsyndromic hearing loss 66;C4015542:Nephronophthisis 19;C4479344:Isolated neonatal sclerosing cholangitis Pathogenic:1
Apr 23, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.78
Mutation Taster
=2/198
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs904944428; hg19: chr6-24301970; API