rs1060500218

Positions:

• chr2-29197676-C-A
• chr2-29197676-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_004304.5(ALK):​c.3939G>T​(p.Trp1313Cys) variant causes a missense, splice region 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. 14/25 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ALK NM_004304.5 missense, splice_region
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

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 (HGNC:):

CLIP4 (HGNC:26108): (CAP-Gly domain containing linker protein family member 4) Predicted to enable microtubule plus-end binding activity. Predicted to be involved in cytoplasmic microtubule organization. Located in intracellular membrane-bounded organelle. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ALK	NM_004304.5	c.3939G>T	p.Trp1313Cys	missense_variant, splice_region_variant	27/29	ENST00000389048.8	NP_004295.2
ALK	NM_001353765.2	c.735G>T	p.Trp245Cys	missense_variant, splice_region_variant	8/10		NP_001340694.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ALK	ENST00000389048.8	c.3939G>T	p.Trp1313Cys	missense_variant, splice_region_variant	27/29	1	NM_004304.5	ENSP00000373700.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuroblastoma, susceptibility to, 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 09, 2016

This sequence change replaces tryptophan with cysteine at codon 1313 of the ALK protein (p.Trp1313Cys). The tryptophan residue is highly conserved and there is a large physicochemical difference between tryptophan and cysteine. It also falls at the first nucleotide of exon 27 of the ALK coding sequence. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with an ALK-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). Algorithms developed to predict the effect of nucleotide changes on mRNA splicing suggest that this variant may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. In summary, this variant is a novel missense change with uncertain impact on protein function and mRNA splicing. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.45	T;D;.
Eigen	Pathogenic	0.98
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	1.0	D;D;D
M_CAP	Pathogenic	0.62	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	.;H;.
PrimateAI	Pathogenic	0.95	D
PROVEAN	Pathogenic	-13	.;D;.
REVEL	Pathogenic	0.91
Sift	Uncertain	0.0010	.;D;.
Sift4G	Pathogenic	0.0010	.;D;D
Polyphen		1.0	.;D;.
Vest4		0.93, 0.93
MutPred		0.92		.;Loss of ubiquitination at K1309 (P = 0.0877);.;
MVP		0.98
MPC		0.90
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.97
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
SpliceAI score (max)		0.39		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.39		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060500218; hg19: chr2-29420542;