20-3688615-A-G

Position:

• chr20-3688615-A-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_023068.4(SIGLEC1):​c.5075T>C​(p.Ile1692Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000692 in 1,445,250 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SIGLEC1 NM_023068.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.170

Genes affected

SIGLEC1 (HGNC:11127): (sialic acid binding Ig like lectin 1) This gene encodes a member of the immunoglobulin superfamily. The encoded protein is a lectin-like adhesion molecule that binds glycoconjugate ligands on cell surfaces in a sialic acid-dependent manner. It is a type I transmembrane protein expressed only by a subpopulation of macrophages and is involved in mediating cell-cell interactions. The protein plays an important role in multiple human diseases and bacterial and viral infections has been shown to enhance SARS-CoV-2 infection. [provided by RefSeq, Dec 2021]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.057509094).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SIGLEC1	NM_023068.4	c.5075T>C	p.Ile1692Thr	missense_variant	22/22	ENST00000344754.6
SIGLEC1	NM_001367089.1	c.5002T>C	p.Leu1668=	synonymous_variant	20/20

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SIGLEC1	ENST00000344754.6	c.5075T>C	p.Ile1692Thr	missense_variant	22/22	1	NM_023068.4	P2
SIGLEC1	ENST00000707083.1	c.5002T>C	p.Leu1668=	synonymous_variant	20/20			A2
SIGLEC1	ENST00000419548.4	c.*1291T>C		3_prime_UTR_variant	5/5	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.92e-7 AC: 1 AN: 1445250 Hom.: 0 Cov.: 30 AF XY: 0.00000139 AC XY: 1 AN XY: 717174

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: 0.0000120

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 22, 2023

The c.5075T>C (p.I1692T) alteration is located in exon 21 (coding exon 21) of the SIGLEC1 gene. This alteration results from a T to C substitution at nucleotide position 5075, causing the isoleucine (I) at amino acid position 1692 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.51
CADD	Benign	4.3
DANN	Benign	0.87
DEOGEN2	Benign	0.064	T
Eigen	Benign	-0.89
Eigen_PC	Benign	-0.86
FATHMM_MKL	Benign	0.048	N
LIST_S2	Benign	0.31	T
M_CAP	Benign	0.0030	T
MetaRNN	Benign	0.058	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.0	L
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.38	T
PROVEAN	Benign	-0.30	N
REVEL	Benign	0.040
Sift	Uncertain	0.0090	D
Sift4G	Benign	0.15	T
Polyphen		0.24	B
Vest4		0.050
MutPred		0.36		Loss of stability (P = 0.0014);
MVP		0.085
MPC		0.14
ClinPred		0.28	T
GERP RS		1.8
Varity_R		0.058
gMVP		0.068

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: rs1785131064; hg19: chr20-3669262;