rs770709355

Positions:

• chr8-144514447-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_004260.4(RECQL4):​c.1699C>T​(p.Gln567Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000336 in 1,459,604 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.000034 (0 hom.)
• Consequence: RECQL4 NM_004260.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 0.523

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]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-144514447-G-A is Pathogenic according to our data. Variant chr8-144514447-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 568068.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RECQL4	NM_004260.4	c.1699C>T	p.Gln567Ter	stop_gained	10/21	ENST00000617875.6	NP_004251.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RECQL4	ENST00000617875.6	c.1699C>T	p.Gln567Ter	stop_gained	10/21	1	NM_004260.4	ENSP00000482313	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000406 AC: 1 AN: 246550 Hom.: 0 AF XY: 0.00000745 AC XY: 1 AN XY: 134290

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: 0.00000898

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000336 AC: 49 AN: 1459604 Hom.: 0 Cov.: 36 AF XY: 0.0000344 AC XY: 25 AN XY: 726004

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: 0.0000441

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

Alfa AF: 0.0000370 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000828 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Rothmund-Thomson syndrome type 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Feb 02, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Baller-Gerold syndrome (MIM#218600), RAPADILINO syndrome (MIM#266280) and Rothmund-Thomson syndrome (MIM#268400). There is currently no phenotype-genotype correlation. (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (v2: 1 heterozygote, 0 homozygotes). (SP) 0701 - Other NMD-predicted variants comparable to the one identified in this case have very strong previous evidence for pathogenicity (ClinVar). (SP) 0803 - This variant has limited previous evidence of pathogenicity in an unrelated individual. It has been classified as pathogenic by a diagnostic laboratory in ClinVar. (SP) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Baller-Gerold syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 02, 2023

This sequence change creates a premature translational stop signal (p.Gln567*) in the RECQL4 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in RECQL4 are known to be pathogenic (PMID: 12734318, 12952869). This variant is present in population databases (rs770709355, gnomAD 0.0009%). 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: 568068). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	36
DANN	Benign	0.91
FATHMM_MKL	Benign	0.35	N
Vest4		0.70
GERP RS		1.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs770709355; hg19: chr8-145739831;