8-144513342-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_004260.4(RECQL4):c.2339G>A(p.Arg780Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000212 in 1,604,512 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R780W) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000020 (0 hom.)
• Consequence: RECQL4 NM_004260.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.45

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]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.33479214).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RECQL4	NM_004260.4	c.2339G>A	p.Arg780Gln	missense_variant	14/21	ENST00000617875.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RECQL4	ENST00000617875.6	c.2339G>A	p.Arg780Gln	missense_variant	14/21	1	NM_004260.4	P1
RECQL4	ENST00000621189.4	c.1268G>A	p.Arg423Gln	missense_variant	13/20	1
	ENST00000580385.1	n.272-264C>T		intron_variant, non_coding_transcript_variant		3
RECQL4	ENST00000534626.6	c.634+74G>A		intron_variant		5

Frequencies

GnomAD3 genomes AF: 0.0000328 AC: 5 AN: 152256 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000482

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000258 AC: 6 AN: 232866 Hom.: 0 AF XY: 0.0000233 AC XY: 3 AN XY: 128762

Gnomad AFR exome AF: 0.0000697

Gnomad AMR exome AF: 0.0000584

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000282

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000200 AC: 29 AN: 1452140 Hom.: 0 Cov.: 47 AF XY: 0.0000194 AC XY: 14 AN XY: 722804

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.000112

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000180

Gnomad4 OTH exome AF: 0.0000332

GnomAD4 genome AF: 0.0000328 AC: 5 AN: 152372 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74510

Gnomad4 AFR AF: 0.0000481

Gnomad4 AMR AF: 0.0000653

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000680

ExAC AF: 0.0000335 AC: 4

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Baller-Gerold syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 21, 2023

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 780 of the RECQL4 protein (p.Arg780Gln). This variant is present in population databases (rs369488194, gnomAD 0.007%). 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: 406945). 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 expected to disrupt RECQL4 protein function with a positive 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	0.16
BayesDel_addAF	Benign	-0.032	T
BayesDel_noAF	Benign	-0.10
Cadd	Uncertain	24
Dann	Benign	0.87
DEOGEN2	Benign	0.081	T;T
FATHMM_MKL	Benign	0.68	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Uncertain	0.18	D
MetaRNN	Benign	0.33	T;T
PrimateAI	Uncertain	0.54	T
Sift4G	Uncertain	0.012	D;D
Polyphen		0.99	.;D
Vest4		0.50
MVP		0.77
GERP RS		5.7
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		2.1
Varity_R		0.23
gMVP		0.60

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: rs369488194; hg19: chr8-145738725;