19-48115878-C-T

Variant summary

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

The NM_000234.3(LIG1):c.2671G>A(p.Ala891Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,382 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LIG1 NM_000234.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.151

Genes affected

LIG1 (HGNC:6598): (DNA ligase 1) This gene encodes a member of the ATP-dependent DNA ligase protein family. The encoded protein functions in DNA replication, recombination, and the base excision repair process. Mutations in this gene that lead to DNA ligase I deficiency result in immunodeficiency and increased sensitivity to DNA-damaging agents. Disruption of this gene may also be associated with a variety of cancers. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]

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=0.045669228).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LIG1	NM_000234.3	c.2671G>A	p.Ala891Thr	missense_variant	27/28	ENST00000263274.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LIG1	ENST00000263274.12	c.2671G>A	p.Ala891Thr	missense_variant	27/28	1	NM_000234.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461382 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 727022

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 22, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The threonine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with LIG1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 891 of the LIG1 protein (p.Ala891Thr). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.077
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.52
Cadd	Benign	15
Dann	Benign	0.84
DEOGEN2	Benign	0.13	T;.;.
Eigen	Benign	-0.75
Eigen_PC	Benign	-0.69
FATHMM_MKL	Benign	0.61	D
LIST_S2	Uncertain	0.89	D;D;D
M_CAP	Benign	0.0095	T
MetaRNN	Benign	0.046	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.5	L;.;.
MutationTaster	Benign	0.99	N;N;N
PrimateAI	Benign	0.34	T
PROVEAN	Benign	-0.32	N;N;N
REVEL	Benign	0.038
Sift	Benign	0.37	T;T;T
Sift4G	Benign	0.44	T;T;T
Polyphen		0.0040	B;B;.
Vest4		0.084
MutPred		0.26		Gain of glycosylation at A891 (P = 0.0449);.;.;
MVP		0.25
MPC		0.27
ClinPred		0.034	T
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.029
gMVP		0.18

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: rs1600296385; hg19: chr19-48619135;