chr2-29920112-C-T

Position:

• chr2-29920112-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_004304.5(ALK):​c.548G>A​(p.Gly183Glu) variant causes a missense change. The variant allele was found at a frequency of 0.0000041 in 1,461,784 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G183V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: ALK NM_004304.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.83

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]

(HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• BS2: High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ALK	NM_004304.5	c.548G>A	p.Gly183Glu	missense_variant	1/29	ENST00000389048.8
ALK	XR_001738688.3	n.1475G>A		non_coding_transcript_exon_variant	1/18

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ALK	ENST00000389048.8	c.548G>A	p.Gly183Glu	missense_variant	1/29	1	NM_004304.5	P1
	ENST00000669284.1	n.157+35137G>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461784 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727198

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neuroblastoma, susceptibility to, 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 24, 2023

ClinVar contains an entry for this variant (Variation ID: 404371). This variant has not been reported in the literature in individuals affected with ALK-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 183 of the ALK protein (p.Gly183Glu). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 05, 2023

The p.G183E variant (also known as c.548G>A), located in coding exon 1 of the ALK gene, results from a G to A substitution at nucleotide position 548. The glycine at codon 183 is replaced by glutamic acid, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.14	T
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Uncertain	0.80	D
LIST_S2	Benign	0.72	T
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.53	D
MetaSVM	Uncertain	0.47	D
MutationAssessor	Benign	0.69	N
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Benign	-1.2	N
REVEL	Uncertain	0.41
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.010	D
Polyphen		1.0	D
Vest4		0.51
MutPred		0.43		Gain of sheet (P = 0.0149);
MVP		0.88
MPC		0.80
ClinPred		0.99	D
GERP RS		5.3
Varity_R		0.47
gMVP		0.61

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1060500223; hg19: chr2-30142978; COSMIC: COSV66580180;