8-144514976-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_004260.4(RECQL4):c.1580C>G(p.Thr527Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000807 in 1,611,844 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. T527A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)

Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

RECQL4
NM_004260.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 4.50

Variant links:

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]

RECQL4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 15 uncertain in NM_004260.4

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RECQL4	NM_004260.4 linkuse as main transcript	c.1580C>G	p.Thr527Arg	missense_variant	9/21	ENST00000617875.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
RECQL4	ENST00000617875.6 linkuse as main transcript	c.1580C>G	p.Thr527Arg	missense_variant	9/21	1	NM_004260.4	P1
RECQL4	ENST00000621189.4 linkuse as main transcript	c.509C>G	p.Thr170Arg	missense_variant	8/20	1
RECQL4	ENST00000532846.2 linkuse as main transcript	c.437C>G	p.Thr146Arg	missense_variant	5/9	5
RECQL4	ENST00000688394.1 linkuse as main transcript	n.603C>G		non_coding_transcript_exon_variant	3/4

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152170

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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

GnomAD3 exomes

AF:

0.00000407

AC:

AN:

245596

Hom.:

AF XY:

0.00000746

AC XY:

AN XY:

133998

show subpopulations

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:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000902

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000754

AC:

AN:

1459674

Hom.:

Cov.:

AF XY:

0.00000964

AC XY:

AN XY:

726074

show subpopulations

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:

0.00000810

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152170

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:2

Revision: criteria provided, single submitter

LINK: link

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 RECQL4 p.Thr527Arg variant was identified in 1 of 1220 proband chromosomes (frequency: 0.00082) from individuals with structural anomalies (Lord_2019_PMID:30712880). The proband was compound heterozygous for the p.T527R variant and a nonsense variant in RECQL4 (Lord_2019_PMID:30712880). The variant was identified in dbSNP (ID: rs766354337) and ClinVar (classified as uncertain significance by Invitae for Baller-Gerold syndrome) but was not identified in LOVD 3.0 or Cosmic. The variant was identified in control databases in 2 of 264196 chromosomes at a frequency of 0.00000757 (Genome Aggregation Database March 6, 2019, v2.1.1, non-cancer). The variant was observed in the following populations: African in 1 of 22550 chromosomes (freq: 0.000044) and European (non-Finnish) in 1 of 116624 chromosomes (freq: 0.000009), but was not observed in the Latino, Ashkenazi Jewish, East Asian, European (Finnish), Other, or South Asian populations. The p.Thr527 residue is conserved across mammals and other organisms, and four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the variant may impact the protein; however, this information is not predictive enough to assume pathogenicity. The variant occurs outside of the splicing consensus sequence and 4 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 5' splice site. However, this has not been confirmed by RNA analysis and 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. -

Baller-Gerold syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 11, 2024

This sequence change replaces threonine, which is neutral and polar, with arginine, which is basic and polar, at codon 527 of the RECQL4 protein (p.Thr527Arg). This variant is present in population databases (no rsID available, gnomAD 0.004%). 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: 528916). 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%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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

Pathogenic

0.94

BayesDel_addAF

Pathogenic

0.46

BayesDel_noAF

Pathogenic

0.42

Cadd

Uncertain

Dann

Benign

0.83

DEOGEN2

Benign

0.23

T;T

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.95

D;D

M_CAP

Benign

0.016

MetaRNN

Pathogenic

0.88

D;D

PrimateAI

Uncertain

0.55

Sift4G

Pathogenic

0.0010

D;D

Polyphen

1.0

.;D

Vest4

0.85

MVP

0.69

GERP RS

4.3

Varity_R

0.91

gMVP

0.86

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.99

Position offset: 0

DS_DL_spliceai

0.33

Position offset: -40

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over