19-10287066-G-A

Position:

• chr19-10287066-G-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001544.5(ICAM4):​c.54G>A​(p.Pro18=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000139 in 1,581,988 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (no stars).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: ICAM4 NM_001544.5 synonymous
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: -0.0860

Genes affected

ICAM4 (HGNC:5347): (intercellular adhesion molecule 4 (Landsteiner-Wiener blood group)) This gene encodes the Landsteiner-Wiener (LW) blood group antigen(s) that belongs to the immunoglobulin (Ig) superfamily, and that shares similarity with the intercellular adhesion molecule (ICAM) protein family. This ICAM protein contains 2 Ig-like C2-type domains and binds to the leukocyte adhesion LFA-1 protein. The molecular basis of the LW(A)/LW(B) blood group antigens is a single aa variation at position 100; Gln-100=LW(A) and Arg-100=LW(B). Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2008]

ICAM4-AS1 (HGNC:55990): (ICAM4 antisense RNA 1)

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.75).
• BP7: Synonymous conserved (PhyloP=-0.086 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ICAM4	NM_001544.5	c.54G>A	p.Pro18=	synonymous_variant	1/3	ENST00000380770.5	NP_001535.1
ICAM4	NM_001039132.3	c.54G>A	p.Pro18=	synonymous_variant	1/3		NP_001034221.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ICAM4	ENST00000380770.5	c.54G>A	p.Pro18=	synonymous_variant	1/3	1	NM_001544.5	ENSP00000370147	P2
ICAM4	ENST00000340992.4	c.54G>A	p.Pro18=	synonymous_variant	1/3	1		ENSP00000342114
ICAM4-AS1	ENST00000589379.1	n.1954C>T		non_coding_transcript_exon_variant	1/1
ICAM4	ENST00000393717.2	c.54G>A	p.Pro18=	synonymous_variant	1/2	2		ENSP00000377320	A2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152180 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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

GnomAD4 exome AF: 0.0000147 AC: 21 AN: 1429808 Hom.: 0 Cov.: 31 AF XY: 0.0000155 AC XY: 11 AN XY: 707478

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000769

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000165

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152180 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74348

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The ICAM4 p.Pro18Pro variant was not identified in the literature nor was it identified in ClinVar, Cosmic, or LOVD 3.0. The variant was identified in dbSNP (ID: rs762283483) and in control databases in 4 of 255224 chromosomes at a frequency of 0.000016 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: East Asian in 1 of 18598 chromosomes (freq: 0.000054) and European (non-Finnish) in 3 of 116222 chromosomes (freq: 0.000026), but not in the African, Latino, Ashkenazi Jewish, European (Finnish), Other, and South Asian populations. The p. Pro18Pro variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. However, 3 of 4 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) predict a greater than 10% difference in splicing and the creation of a new 3' splice site. However, this information is not predictive enough to assume pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.75
CADD	Benign	4.3
DANN	Benign	0.87
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs762283483; hg19: chr19-10397742;