NM_004304.5:c.920_922dupCTG

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 1P and 4B. PM4_SupportingBS2

The NM_004304.5(ALK):​c.920_922dupCTG​(p.Pro307_Gly308insAla) variant causes a conservative inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000644 in 1,613,888 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. G308G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000068 ( 0 hom. )

Consequence

ALK
NM_004304.5 conservative_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 3.08

Publications

1 publications found
Variant links:
Genes affected
ALK (HGNC:427): (ALK receptor tyrosine kinase) This gene encodes a receptor tyrosine kinase, which belongs to the insulin receptor superfamily. This protein comprises an extracellular domain, an hydrophobic stretch corresponding to a single pass transmembrane region, and an intracellular kinase domain. It plays an important role in the development of the brain and exerts its effects on specific neurons in the nervous system. This gene has been found to be rearranged, mutated, or amplified in a series of tumours including anaplastic large cell lymphomas, neuroblastoma, and non-small cell lung cancer. The chromosomal rearrangements are the most common genetic alterations in this gene, which result in creation of multiple fusion genes in tumourigenesis, including ALK (chromosome 2)/EML4 (chromosome 2), ALK/RANBP2 (chromosome 2), ALK/ATIC (chromosome 2), ALK/TFG (chromosome 3), ALK/NPM1 (chromosome 5), ALK/SQSTM1 (chromosome 5), ALK/KIF5B (chromosome 10), ALK/CLTC (chromosome 17), ALK/TPM4 (chromosome 19), and ALK/MSN (chromosome X).[provided by RefSeq, Jan 2011]
ALK Gene-Disease associations (from GenCC):
  • neuroblastoma, susceptibility to, 3
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

PM4
Nonframeshift variant in NON repetitive region in NM_004304.5. Strenght limited to Supporting due to length of the change: 1aa.
BS2
High AC in GnomAdExome4 at 100 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALKNM_004304.5 linkc.920_922dupCTG p.Pro307_Gly308insAla conservative_inframe_insertion Exon 3 of 29 ENST00000389048.8 NP_004295.2 Q9UM73B6D4Y2
ALKXR_001738688.3 linkn.1847_1849dupCTG non_coding_transcript_exon_variant Exon 3 of 18

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALKENST00000389048.8 linkc.920_922dupCTG p.Pro307_Gly308insAla conservative_inframe_insertion Exon 3 of 29 1 NM_004304.5 ENSP00000373700.3 Q9UM73
ALKENST00000618119.4 linkc.-212_-210dupCTG 5_prime_UTR_variant Exon 2 of 28 5 ENSP00000482733.1 A0A087WZL3

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152188
Hom.:
0
Cov.:
33
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000319
AC:
8
AN:
250818
AF XY:
0.0000443
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:
0.0000707
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000684
AC:
100
AN:
1461700
Hom.:
0
Cov.:
32
AF XY:
0.0000646
AC XY:
47
AN XY:
727152
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53386
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5720
European-Non Finnish (NFE)
AF:
0.0000854
AC:
95
AN:
1111936
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
9
17
26
34
43
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000263
AC:
4
AN:
152188
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.000142
Hom.:
0
Bravo
AF:
0.0000416
EpiCase
AF:
0.000218
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

Neuroblastoma, susceptibility to, 3 Uncertain:2
Feb 26, 2024
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant, c.920_922dup, results in the insertion of 1 amino acid(s) of the ALK protein (p.Pro307_Gly308insAla), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs746818719, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with ALK-related conditions. ClinVar contains an entry for this variant (Variation ID: 404375). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

not specified Uncertain:1
Nov 07, 2022
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

DNA sequence analysis of the ALK gene demonstrated a three base pair duplication in exon 3, c.920_922dup. This in-frame duplication is predicted to result in the insertion of one amino acid residue, p.Pro307_Gly308insAla. This duplication does not appear to have been previously described in individuals with ALK -related disorders. This sequence change has been described in the gnomAD database with a frequency of 0.0032% in the overall population (dbSNP rs746818719). The functional significance of this sequence change is not known at present and its contribution to this individual's disease phenotype cannot definitively be determined. -

ALK-related disorder Uncertain:1
Mar 19, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The ALK c.920_922dupCTG variant is predicted to result in an in-frame duplication (p.Pro307_Gly308insAla). To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0071% of alleles in individuals of European (Non-Finnish) descent in gnomAD. In ClinVar, this variant is interpreted as uncertain (https://www.ncbi.nlm.nih.gov/clinvar/variation/404375/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

not provided Uncertain:1
Mar 14, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In-frame insertion of 1 amino acid in a non-repeat region; In silico analysis supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Hereditary cancer-predisposing syndrome Uncertain:1
Dec 16, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.920_922dupCTG variant (also known as p.P307_G308insA), located in coding exon 3 of the ALK gene, results from an in-frame duplication of CTG at nucleotide positions 920 to 922. This results in the insertion of an alanine residue between codons 307 and 308. This amino acid region is well conserved in available vertebrate species. In addition, this alteration is predicted to be neutral by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
3.1
Mutation Taster
=76/24
polymorphism

Splicing

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

Publications

Other links and lift over

dbSNP: rs746818719; hg19: chr2-29917745; API