8-144512481-A-G

Variant names:

• chr8-144512481-A-G
• rs767220757
• NM_004260.4:c.2966T>C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_004260.4(RECQL4):​c.2966T>C​(p.Met989Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,460,086 control chromosomes in the GnomAD database, with no homozygous occurrence. 9/14 in silico tools predict a benign outcome for this variant. 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. M989I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: RECQL4 NM_004260.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.53

Genes affected

RECQL4 (HGNC:9949): (RecQ like helicase 4) The protein encoded by this gene is a DNA helicase that belongs to the RecQ helicase family. DNA helicases unwind double-stranded DNA into single-stranded DNAs and may modulate chromosome segregation. This gene is predominantly expressed in thymus and testis. Mutations in this gene are associated with Rothmund-Thomson, RAPADILINO and Baller-Gerold syndromes. [provided by RefSeq, Jan 2010]

ENSG00000265393 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RECQL4	NM_004260.4	c.2966T>C	p.Met989Thr	missense_variant	Exon 17 of 21	ENST00000617875.6	NP_004251.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RECQL4	ENST00000617875.6	c.2966T>C	p.Met989Thr	missense_variant	Exon 17 of 21	1	NM_004260.4	ENSP00000482313.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.0000122 AC: 3 AN: 246434 Hom.: 0 AF XY: 0.0000149 AC XY: 2 AN XY: 134554

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000981

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1460086 Hom.: 0 Cov.: 66 AF XY: 0.00000413 AC XY: 3 AN XY: 726284

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: 0.0000232

Gnomad4 FIN exome AF: 0.0000192

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 34

Alfa AF: 0.0000254 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Baller-Gerold syndrome Uncertain:1

Dec 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 989 of the RECQL4 protein (p.Met989Thr). This variant is present in population databases (no rsID available, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with RECQL4-related conditions. ClinVar contains an entry for this variant (Variation ID: 1053672). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt RECQL4 protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Benign	-0.10	T
BayesDel_noAF	Benign	-0.18
CADD	Benign	20
DANN	Benign	0.68
DEOGEN2	Benign	0.027	T;T;T
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.77	T;T;T
M_CAP	Benign	0.020	T
MetaRNN	Uncertain	0.44	T;T;T
MutationAssessor	Benign	1.0	.;L;.
PrimateAI	Benign	0.32	T
Sift4G	Uncertain	0.0030	D;D;D
Polyphen		0.0010	.;B;.
Vest4		0.27
MVP		0.41
GERP RS		5.3
Varity_R		0.43
gMVP		0.59

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs767220757; hg19: chr8-145737864;