NM_004260.4:c.1864C>G

Variant names:

• chr8-144514203-G-C
• rs373717016
• NM_004260.4:c.1864C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_004260.4(RECQL4):​c.1864C>G​(p.Leu622Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,612,250 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. L622L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 34)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: RECQL4 NM_004260.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.52
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• Baller-Gerold syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, G2P, Orphanet
• Rothmund-Thomson syndrome

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Rothmund-Thomson syndrome type 2

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, G2P
• osteosarcoma

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
• rapadilino syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

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

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004260.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RECQL4	NM_004260.4	MANE Select	c.1864C>G	p.Leu622Val	missense	Exon 11 of 21	NP_004251.4
	RECQL4	NM_001413019.1		c.1864C>G	p.Leu622Val	missense	Exon 11 of 20	NP_001399948.1
	RECQL4	NM_001413036.1		c.1864C>G	p.Leu622Val	missense	Exon 11 of 21	NP_001399965.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RECQL4	ENST00000617875.6	TSL:1 MANE Select	c.1864C>G	p.Leu622Val	missense	Exon 11 of 21	ENSP00000482313.2
	RECQL4	ENST00000621189.4	TSL:1	c.793C>G	p.Leu265Val	missense	Exon 10 of 20	ENSP00000483145.1
	RECQL4	ENST00000534626.6	TSL:5	c.232C>G	p.Leu78Val	missense	Exon 2 of 8	ENSP00000477457.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152140 Hom.: 0 Cov.: 34

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460110 Hom.: 0 Cov.: 36 AF XY: 0.00000138 AC XY: 1 AN XY: 726340

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44688

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52016

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111750

Other (OTH) AF: 0.00 AC: 0 AN: 60340

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152140 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 74318

African (AFR) AF: 0.0000241 AC: 1 AN: 41418

American (AMR) AF: 0.00 AC: 0 AN: 15276

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4838

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10626

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Jan 05, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L622V variant (also known as c.1864C>G), located in coding exon 11 of the RECQL4 gene, results from a C to G substitution at nucleotide position 1864. The leucine at codon 622 is replaced by valine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear.

Baller-Gerold syndrome Uncertain:1

Oct 26, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 622 of the RECQL4 protein (p.Leu622Val). This variant is not present in population databases (gnomAD no frequency). 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: 2080943). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.46
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Benign	19
DANN	Benign	0.87
DEOGEN2	Benign	0.10	T
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Benign	0.86	D
M_CAP	Benign	0.040	D
MetaRNN	Uncertain	0.44	T
PhyloP100		2.5
PrimateAI	Uncertain	0.61	T
Sift4G	Uncertain	0.010	D
Polyphen		0.94	P
Vest4		0.58
MVP		0.40
GERP RS		3.1
PromoterAI		0.075	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.41
gMVP		0.55
Mutation Taster		=76/24	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs373717016; hg19: chr8-145739587;